From ab26f518dac3951562598488a3f6d5535eb5df7d Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Mon, 31 Oct 2016 01:30:04 +0000
Subject: [PATCH 01/30] Added BokehRenderer server mode

---
 holoviews/plotting/bokeh/plot.py     | 12 +++++++++++
 holoviews/plotting/bokeh/renderer.py | 30 ++++++++++++++++++++++++----
 holoviews/plotting/renderer.py       |  1 +
 3 files changed, 39 insertions(+), 4 deletions(-)

diff --git a/holoviews/plotting/bokeh/plot.py b/holoviews/plotting/bokeh/plot.py
index d40b30af28..a7b06765c8 100644
--- a/holoviews/plotting/bokeh/plot.py
+++ b/holoviews/plotting/bokeh/plot.py
@@ -81,6 +81,18 @@ def get_data(self, element, ranges=None, empty=False):
         raise NotImplementedError
 
 
+    def push(self):
+        """
+        Pushes updated plot data via the Comm.
+        """
+        if self.renderer.mode == 'server':
+            return
+        if self.comm is None:
+            raise Exception('Renderer does not have a comm.')
+        diff = self.renderer.diff(self)
+        self.comm.send(diff)
+
+
     def set_root(self, root):
         """
         Sets the current document on all subplots.
diff --git a/holoviews/plotting/bokeh/renderer.py b/holoviews/plotting/bokeh/renderer.py
index a27e8dedfa..85bc301fc6 100644
--- a/holoviews/plotting/bokeh/renderer.py
+++ b/holoviews/plotting/bokeh/renderer.py
@@ -7,13 +7,14 @@
 from bokeh.charts import Chart
 from bokeh.document import Document
 from bokeh.embed import notebook_div
-from bokeh.io import load_notebook
+from bokeh.io import load_notebook, curdoc
 from bokeh.models import (Row, Column, Plot, Model, ToolbarBox,
                           WidgetBox, Div, DataTable, Tabs)
 from bokeh.plotting import Figure
 from bokeh.resources import CDN, INLINE
 
 from ...core import Store, HoloMap
+from ..comms import JupyterComm, Comm
 from ..renderer import Renderer, MIME_TYPES
 from .widgets import BokehScrubberWidget, BokehSelectionWidget
 from .util import compute_static_patch, serialize_json
@@ -28,9 +29,15 @@ class BokehRenderer(Renderer):
         Output render format for static figures. If None, no figure
         rendering will occur. """)
 
+    mode = param.ObjectSelector(default='default',
+                                objects=['default', 'server'], doc="""
+         Whether to render the DynamicMap in regular or server mode. """)
+
     # Defines the valid output formats for each mode.
-    mode_formats = {'fig': {'default': ['html', 'json', 'auto']},
-                    'holomap': {'default': ['widgets', 'scrubber', 'auto', None]}}
+    mode_formats = {'fig': {'default': ['html', 'json', 'auto'],
+                            'server': ['html', 'json', 'auto']},
+                    'holomap': {'default': ['widgets', 'scrubber', 'auto', None],
+                                'server': ['widgets', 'auto', None]}}
 
     webgl = param.Boolean(default=False, doc="""Whether to render plots with WebGL
         if bokeh version >=0.10""")
@@ -41,6 +48,9 @@ class BokehRenderer(Renderer):
     backend_dependencies = {'js': CDN.js_files if CDN.js_files else tuple(INLINE.js_raw),
                             'css': CDN.css_files if CDN.css_files else tuple(INLINE.css_raw)}
 
+    comms = {'default': (JupyterComm, None),
+             'server': (Comm, None)}
+
     _loaded = False
 
     def __call__(self, obj, fmt=None):
@@ -52,7 +62,9 @@ def __call__(self, obj, fmt=None):
         plot, fmt =  self._validate(obj, fmt)
         info = {'file-ext': fmt, 'mime_type': MIME_TYPES[fmt]}
 
-        if isinstance(plot, tuple(self.widgets.values())):
+        if self.mode == 'server':
+            return self.server_doc(plot), info
+        elif isinstance(plot, tuple(self.widgets.values())):
             return plot(), info
         elif fmt == 'html':
             html = self.figure_data(plot)
@@ -62,6 +74,16 @@ def __call__(self, obj, fmt=None):
             return self.diff(plot), info
 
 
+    def server_doc(self, plot):
+        """
+        Get server document.
+        """
+        doc = curdoc()
+        plot.document = doc
+        doc.add_root(plot.state)
+        return doc
+
+
     def figure_data(self, plot, fmt='html', **kwargs):
         model = plot.state
         doc = Document()
diff --git a/holoviews/plotting/renderer.py b/holoviews/plotting/renderer.py
index 26318b40e4..b63dbfbe31 100644
--- a/holoviews/plotting/renderer.py
+++ b/holoviews/plotting/renderer.py
@@ -52,6 +52,7 @@
     'pdf':  'application/pdf',
     'html':  'text/html',
     'json':  'text/json'
+    'server': None
 }
 
 static_template = """

From c1e2550b38eff28352cf178b4a61898892533613 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Mon, 31 Oct 2016 01:30:32 +0000
Subject: [PATCH 02/30] Added initial bokeh server stream callback handling

---
 holoviews/plotting/bokeh/callbacks.py | 114 ++++++++++++++++++++------
 holoviews/plotting/renderer.py        |   2 +-
 2 files changed, 89 insertions(+), 27 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index 8ec1fc395e..b5c45c3c8f 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -229,10 +229,13 @@ class Callback(object):
     def __init__(self, plot, streams, source, **params):
         self.plot = plot
         self.streams = streams
-        self.comm = self._comm_type(plot, on_msg=self.on_msg)
+        if plot.renderer.mode != 'server':
+            self.comm = self._comm_type(plot, on_msg=self.on_msg)
         self.source = source
         self.handle_ids = defaultdict(dict)
         self.callbacks = []
+        self.plot_handles = {}
+        self._event_queue = []
 
 
     def initialize(self):
@@ -240,28 +243,45 @@ def initialize(self):
         if self.plot.subplots:
             plots += list(self.plot.subplots.values())
 
-        handles = self._get_plot_handles(plots)
+        self.plot_handles = self._get_plot_handles(plots)
         requested = {}
         for h in self.models+self.extra_models:
-            if h in handles:
-                requested[h] = handles[h]
+            if h in self.plot_handles:
+                requested[h] = self.plot_handles[h]
             elif h in self.extra_models:
                 print("Warning %s could not find the %s model. "
                       "The corresponding stream may not work.")
         self.handle_ids.update(self._get_stream_handle_ids(requested))
 
+        found = []
         for plot in plots:
             for handle_name in self.models:
-                if handle_name not in handles:
+                if handle_name not in self.plot_handles:
                     warn_args = (handle_name, type(self.plot).__name__,
                                  type(self).__name__)
-                    self.warning('%s handle not found on %s, cannot'
-                                 'attach %s callback' % warn_args)
+                    print('%s handle not found on %s, cannot '
+                          'attach %s callback' % warn_args)
                     continue
-                handle = handles[handle_name]
-                js_callback = self.get_customjs(requested)
-                self.set_customjs(js_callback, handle)
-                self.callbacks.append(js_callback)
+                handle = self.plot_handles[handle_name]
+
+                # Hash the plot handle with Callback type allowing multiple
+                # callbacks on one handle to be merged
+                cb_hash = (id(handle), id(type(self)))
+                if cb_hash in self._callbacks:
+                    # Merge callbacks if another callback has already been attached
+                    cb = self._callbacks[cb_hash]
+                    cb.streams += self.streams
+                    for k, v in self.handle_ids.items():
+                        cb.handle_ids[k].update(v)
+                    continue
+
+                if self.plot.renderer.mode == 'server':
+                    self.set_onchange(plot.handles[handle_name])
+                else:
+                    js_callback = self.get_customjs(requested)
+                    self.set_customjs(js_callback, handle)
+                    self.callbacks.append(js_callback)
+                self._callbacks[cb_hash] = self
 
 
     def _filter_msg(self, msg, ids):
@@ -278,7 +298,7 @@ def _filter_msg(self, msg, ids):
             else:
                 filtered_msg[k] = v
         return filtered_msg
-
+    
 
     def on_msg(self, msg):
         for stream in self.streams:
@@ -330,7 +350,61 @@ def _get_stream_handle_ids(self, handles):
         return stream_handle_ids
 
 
-    def get_customjs(self, references):
+    def on_change(self, attr, old, new):
+        """
+        Process change events adding timeout to process multiple concerted
+        value change at once rather than firing off multiple plot updates.
+        """
+        self._event_queue.append((attr, old, new))
+        if self.trigger not in self.plot.document._session_callbacks:
+            self.plot.document.add_timeout_callback(self.trigger, 50)
+
+
+    def trigger(self):
+        """
+        Trigger callback change event and triggering corresponding streams.
+        """
+        if not self._event_queue:
+            return
+
+        values = {}
+        for attr, path in self.attributes.items():
+            attr_path = path.split('.')
+            if attr_path[0] == 'cb_obj':
+                attr_path = self.models[0]
+            obj = self.plot_handles.get(attr_path[0])
+            if not obj:
+                raise Exception('Bokeh plot attribute %s could not be found' % path)
+            for p in attr_path[1:]:
+                if p == 'attributes':
+                    continue
+                if isinstance(obj, dict):
+                    obj = obj.get(p)
+                else:
+                    obj = getattr(obj, p, None)
+            values[attr] = obj
+        values = self._process_msg(values)
+        if any(v is None for v in values.values()):
+            return
+        for stream in self.streams:
+            stream.update(trigger=False, **values)
+        Stream.trigger(self.streams)
+        self._event_queue = []
+
+
+    def set_onchange(self, handle):
+        """
+        Set up on_change events for bokeh server interactions.
+        """
+        if self.events and bokeh_version >= '0.12.5':
+            for event in self.events:
+                handle.on_event(event, self.on_change)
+        elif self.change:
+            for change in self.change:
+                handle.on_change(change, self.on_change)
+
+
+    def set_customjs(self, handle, references):
         """
         Creates a CustomJS callback that will send the requested
         attributes back to python.
@@ -357,23 +431,11 @@ def set_customjs(self, js_callback, handle):
         the requested callback handle.
         """
 
-        # Hash the plot handle with Callback type allowing multiple
-        # callbacks on one handle to be merged
-        cb_hash = (id(handle), id(type(self)))
-        if cb_hash in self._callbacks:
-            # Merge callbacks if another callback has already been attached
-            cb = self._callbacks[cb_hash]
-            if isinstance(cb, type(self)):
-                cb.streams += self.streams
-                for k, v in self.handle_ids.items():
-                    cb.handle_ids[k].update(v)
-            return
-
         self._callbacks[cb_hash] = self
         if self.events and bokeh_version >= '0.12.5':
             for event in self.events:
                 handle.js_on_event(event, js_callback)
-        elif self.change and bokeh_version >= '0.12.5':
+        elif self.change:
             for change in self.change:
                 handle.js_on_change(change, js_callback)
         elif hasattr(handle, 'callback'):
diff --git a/holoviews/plotting/renderer.py b/holoviews/plotting/renderer.py
index b63dbfbe31..13cec36302 100644
--- a/holoviews/plotting/renderer.py
+++ b/holoviews/plotting/renderer.py
@@ -51,7 +51,7 @@
     'mp4':  'video/mp4',
     'pdf':  'application/pdf',
     'html':  'text/html',
-    'json':  'text/json'
+    'json':  'text/json',
     'server': None
 }
 

From afec80feabe9edda57ecb2d881ed1bfac5d68c85 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Mon, 31 Oct 2016 13:47:16 +0000
Subject: [PATCH 03/30] Small fixes for bokeh server implementation

---
 holoviews/plotting/bokeh/renderer.py | 16 +++++++++++++---
 holoviews/plotting/renderer.py       |  4 +++-
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/holoviews/plotting/bokeh/renderer.py b/holoviews/plotting/bokeh/renderer.py
index 85bc301fc6..fdc598b869 100644
--- a/holoviews/plotting/bokeh/renderer.py
+++ b/holoviews/plotting/bokeh/renderer.py
@@ -29,6 +29,12 @@ class BokehRenderer(Renderer):
         Output render format for static figures. If None, no figure
         rendering will occur. """)
 
+    holomap = param.ObjectSelector(default='auto',
+                                   objects=['widgets', 'scrubber', 'server',
+                                            None, 'auto'], doc="""
+        Output render multi-frame (typically animated) format. If
+        None, no multi-frame rendering will occur.""")
+
     mode = param.ObjectSelector(default='default',
                                 objects=['default', 'server'], doc="""
          Whether to render the DynamicMap in regular or server mode. """)
@@ -37,13 +43,14 @@ class BokehRenderer(Renderer):
     mode_formats = {'fig': {'default': ['html', 'json', 'auto'],
                             'server': ['html', 'json', 'auto']},
                     'holomap': {'default': ['widgets', 'scrubber', 'auto', None],
-                                'server': ['widgets', 'auto', None]}}
+                                'server': ['server', 'auto', None]}}
 
     webgl = param.Boolean(default=False, doc="""Whether to render plots with WebGL
         if bokeh version >=0.10""")
 
     widgets = {'scrubber': BokehScrubberWidget,
-               'widgets': BokehSelectionWidget}
+               'widgets': BokehSelectionWidget,
+               'server': BokehServerWidgets}
 
     backend_dependencies = {'js': CDN.js_files if CDN.js_files else tuple(INLINE.js_raw),
                             'css': CDN.css_files if CDN.css_files else tuple(INLINE.css_raw)}
@@ -79,7 +86,10 @@ def server_doc(self, plot):
         Get server document.
         """
         doc = curdoc()
-        plot.document = doc
+        if isinstance(plot, BokehServerWidgets):
+            plot.plot.document = doc
+        else:
+            plot.document = doc
         doc.add_root(plot.state)
         return doc
 
diff --git a/holoviews/plotting/renderer.py b/holoviews/plotting/renderer.py
index 13cec36302..00d2daead0 100644
--- a/holoviews/plotting/renderer.py
+++ b/holoviews/plotting/renderer.py
@@ -299,7 +299,9 @@ def get_widget(self_or_cls, plot, widget_type, **kwargs):
         if not isinstance(plot, Plot):
             plot = self_or_cls.get_plot(plot)
         dynamic = plot.dynamic
-        if widget_type == 'auto':
+        if widget_type == 'server':
+            pass
+        elif widget_type == 'auto':
             isuniform = plot.uniform
             if not isuniform:
                 widget_type = 'scrubber'

From 312975e1c1bb8270f4e742f7ccdbf91deeb9820b Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Mon, 31 Oct 2016 13:48:05 +0000
Subject: [PATCH 04/30] Added initial BokehServerWidgets implementation

---
 holoviews/plotting/bokeh/widgets.py | 149 ++++++++++++++++++++++++++++
 1 file changed, 149 insertions(+)

diff --git a/holoviews/plotting/bokeh/widgets.py b/holoviews/plotting/bokeh/widgets.py
index 345710be1e..29b79874f9 100644
--- a/holoviews/plotting/bokeh/widgets.py
+++ b/holoviews/plotting/bokeh/widgets.py
@@ -1,12 +1,161 @@
+from __future__ import unicode_literals
+
 import json
+from functools import partial
 
 import param
 from bokeh.io import _CommsHandle
 from bokeh.util.notebook import get_comms
+from bokeh.models.widgets import Select, Slider, AutocompleteInput, TextInput
+from bokeh.layouts import layout, gridplot, widgetbox, row, column
 
+from ...core import Store, NdMapping, OrderedDict
+from ...core.util import drop_streams, unique_array, isnumeric, wrap_tuple_streams
 from ..widgets import NdWidget, SelectionWidget, ScrubberWidget
 from .util import serialize_json
 
+
+
+class BokehServerWidgets(param.Parameterized):
+    """
+    """
+
+    position = param.ObjectSelector(default='right',
+        objects=['right', 'left', 'above', 'below'])
+
+    sizing_mode = param.ObjectSelector(default='fixed',
+        objects=['fixed', 'stretch_both', 'scale_width',
+                 'scale_height', 'scale_both'])
+
+    def __init__(self, plot, renderer=None, **params):
+        super(BokehServerWidgets, self).__init__(**params)
+        self.plot = plot
+        streams = []
+        for stream in plot.streams:
+            if any(k in plot.dimensions for k in stream.contents):
+                streams.append(stream)
+        self.dimensions, self.keys = drop_streams(streams,
+                                                  plot.dimensions,
+                                                  plot.keys)
+        if renderer is None:
+            backend = Store.current_backend
+            self.renderer = Store.renderers[backend]
+        else:
+            self.renderer = renderer
+        # Create mock NdMapping to hold the common dimensions and keys
+        self.mock_obj = NdMapping([(k, None) for k in self.keys],
+                                  kdims=self.dimensions)
+        self.widgets, self.lookups = self.get_widgets()
+        self.reverse_lookups = {d: {v: k for k, v in item.items()}
+                                for d, item in self.lookups.items()}
+        self.subplots = {}
+        if self.plot.renderer.mode == 'default':
+            self.attach_callbacks()
+        self.state = self.init_layout()
+
+
+    def get_widgets(self):
+        # Generate widget data
+        widgets = OrderedDict()
+        lookups = {}
+        for idx, dim in enumerate(self.mock_obj.kdims):
+            label, lookup = None, None
+            if self.plot.dynamic:
+                if dim.values:
+                    if all(isnumeric(v) for v in dim.values):
+                        values = dim.values
+                        labels = [unicode(dim.pprint_value(v)) for v in dim.values]
+                        label = AutocompleteInput(value=labels[0], completions=labels,
+                                                  title=dim.pprint_label)
+                        widget = Slider(value=0, end=len(dim.values)-1, title=None, step=1)
+                        lookup = zip(values, labels)
+                    else:
+                        values = [(v, dim.pprint_value(v)) for v in dim.values]
+                        widget = Select(title=dim.pprint_label, value=dim_vals[0][0],
+                                        options=values)
+                else:
+                    start = dim.soft_range[0] if dim.soft_range[0] else dim.range[0]
+                    end = dim.soft_range[1] if dim.soft_range[1] else dim.range[1]
+                    int_type = isinstance(dim.type, type) and issubclass(dim.type, int)
+                    if isinstance(dim_range, int) or int_type:
+                        step = 1
+                    else:
+                        step = 10**(round(math.log10(dim_range))-3)
+                    label = TextInput(value=str(start), title=dim.pprint_label)
+                    widget = Slider(value=start, start=start,
+                                    end=end, step=step, title=None)
+            else:
+                values = (dim.values if dim.values else
+                            list(unique_array(self.mock_obj.dimension_values(dim.name))))
+                labels = [str(dim.pprint_value(v)) for v in values]
+                if isinstance(values[0], np.datetime64) or isnumeric(values[0]):
+                    label = AutocompleteInput(value=labels[0], completions=labels,
+                                              title=dim.pprint_label)
+                    widget = Slider(value=0, end=len(dim.values)-1, title=None)
+                else:
+                    widget = Select(title=dim.pprint_label, value=values[0],
+                                    options=list(zip(values, labels)))
+                lookup = zip(values, labels)
+            if label:
+                label.on_change('value', partial(self.update, dim.pprint_label, 'label'))
+            widget.on_change('value', partial(self.update, dim.pprint_label, 'widget'))
+            widgets[dim.pprint_label] = (label, widget)
+            if lookup:
+                lookups[dim.pprint_label] = OrderedDict(lookup)
+        return widgets, lookups
+
+
+    def init_layout(self):
+        widgets = [widget for d in self.widgets.values()
+                   for widget in d if widget]
+        wbox = widgetbox(widgets, width=200)
+        if self.position in ['right', 'below']:
+            plots = [self.plot.state, wbox]
+        else:
+            plots = [wbox, self.plot.state]
+        layout_fn = row if self.position in ['left', 'right'] else column
+        layout = layout_fn(plots, sizing_mode=self.sizing_mode)
+        return layout
+
+
+    def attach_callbacks(self):
+        """
+        Attach callbacks to interact with Comms.
+        """
+        pass
+
+
+    def update(self, dim, widget_type, attr, old, new):
+        """
+        Handle update events on bokeh server.
+        """
+        label, widget = self.widgets[dim]
+        if widget_type == 'label':
+            if isinstance(label, AutocompleteInput):
+                value = self.reverse_lookups[dim][new]
+                widget.value = value
+            else:
+                widget.value = new
+        else:
+            if label:
+                text = self.lookups[dim][new]
+                label.value = text
+        key = []
+        for dim, (label, widget) in self.widgets.items():
+            if label:
+                if isinstance(label, AutocompleteInput):
+                    val = self.lookups[dim].keys()[widget.value]
+                else:
+                    val = new
+            else:
+                val = widget.value
+            key.append(val)
+        key = wrap_tuple_streams(tuple(key), self.plot.dimensions,
+                                 self.plot.streams)
+        self.plot.update(key)
+
+
+
 class BokehWidget(NdWidget):
 
     css = param.String(default='bokehwidgets.css', doc="""

From 6f420b3a77d534dbd2f5db75b95547f51d66b84e Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Mon, 31 Oct 2016 18:33:08 +0000
Subject: [PATCH 05/30] Fixes for BokehServerWidgets

---
 holoviews/plotting/bokeh/widgets.py | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/holoviews/plotting/bokeh/widgets.py b/holoviews/plotting/bokeh/widgets.py
index 29b79874f9..e26ed60b60 100644
--- a/holoviews/plotting/bokeh/widgets.py
+++ b/holoviews/plotting/bokeh/widgets.py
@@ -71,7 +71,7 @@ def get_widgets(self):
                         lookup = zip(values, labels)
                     else:
                         values = [(v, dim.pprint_value(v)) for v in dim.values]
-                        widget = Select(title=dim.pprint_label, value=dim_vals[0][0],
+                        widget = Select(title=dim.pprint_label, value=values[0][0],
                                         options=values)
                 else:
                     start = dim.soft_range[0] if dim.soft_range[0] else dim.range[0]
@@ -135,18 +135,15 @@ def update(self, dim, widget_type, attr, old, new):
                 value = self.reverse_lookups[dim][new]
                 widget.value = value
             else:
-                widget.value = new
+                widget.value = float(new)
         else:
             if label:
                 text = self.lookups[dim][new]
                 label.value = text
         key = []
         for dim, (label, widget) in self.widgets.items():
-            if label:
-                if isinstance(label, AutocompleteInput):
-                    val = self.lookups[dim].keys()[widget.value]
-                else:
-                    val = new
+            if label and isinstance(label, AutocompleteInput):
+                val = list(self.lookups[dim].keys())[widget.value]
             else:
                 val = widget.value
             key.append(val)

From 3b5d10c7c480bb632e2f4adb62b4f8eecc13b4b8 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 4 Nov 2016 13:35:47 +0000
Subject: [PATCH 06/30] Ensure all subplots have the same plotting classes

---
 holoviews/plotting/bokeh/plot.py | 2 ++
 holoviews/plotting/mpl/plot.py   | 4 ++--
 holoviews/plotting/plot.py       | 1 +
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/holoviews/plotting/bokeh/plot.py b/holoviews/plotting/bokeh/plot.py
index a7b06765c8..dd8e5a5865 100644
--- a/holoviews/plotting/bokeh/plot.py
+++ b/holoviews/plotting/bokeh/plot.py
@@ -354,6 +354,7 @@ def _create_subplots(self, layout, ranges):
             else:
                 subplot = plotting_class(view, dimensions=self.dimensions,
                                          show_title=False, subplot=True,
+                                         renderer=self.renderer,
                                          ranges=frame_ranges, uniform=self.uniform,
                                          keys=self.keys, **dict(opts, **kwargs))
                 collapsed_layout[coord] = (subplot.layout
@@ -581,6 +582,7 @@ def _create_subplots(self, layout, positions, layout_dimensions, ranges, num=0):
                                 layout_dimensions=layout_dimensions,
                                 ranges=ranges, subplot=True,
                                 uniform=self.uniform, layout_num=num,
+                                renderer=self.renderer,
                                 **dict({'shared_axes': self.shared_axes},
                                        **plotopts))
             subplots[pos] = subplot
diff --git a/holoviews/plotting/mpl/plot.py b/holoviews/plotting/mpl/plot.py
index f17e996e77..215d5c363c 100644
--- a/holoviews/plotting/mpl/plot.py
+++ b/holoviews/plotting/mpl/plot.py
@@ -406,7 +406,7 @@ def _create_subplots(self, layout, axis, ranges, create_axes):
                               dimensions=self.dimensions, show_title=False,
                               subplot=not create_axes, ranges=frame_ranges,
                               uniform=self.uniform, keys=self.keys,
-                              show_legend=False)
+                              show_legend=False, renderer=self.renderer)
                 plotting_class = Store.registry['matplotlib'][vtype]
                 subplot = plotting_class(view,  **dict(opts, **dict(params, **kwargs)))
                 collapsed_layout[coord] = subplot.layout if isinstance(subplot, CompositePlot) else subplot.hmap
@@ -1022,7 +1022,7 @@ def _create_subplots(self, layout, positions, layout_dimensions, ranges, axes={}
                                       layout_dimensions=layout_dimensions,
                                       ranges=ranges, subplot=True,
                                       uniform=self.uniform, layout_num=num,
-                                      **plotopts)
+                                      renderer=self.renderer, **plotopts)
             if isinstance(view, (Element, HoloMap, Collator, CompositeOverlay)):
                 adjoint_clone[pos] = subplots[pos].hmap
             else:
diff --git a/holoviews/plotting/plot.py b/holoviews/plotting/plot.py
index 731d905e79..3d38ca3626 100644
--- a/holoviews/plotting/plot.py
+++ b/holoviews/plotting/plot.py
@@ -895,6 +895,7 @@ def _create_subplots(self, ranges):
                             layout_dimensions=self.layout_dimensions,
                             ranges=ranges, show_title=self.show_title,
                             style=style, uniform=self.uniform,
+                            renderer=self.renderer,
                             zorder=zorder, **passed_handles)
 
             if not isinstance(key, tuple): key = (key,)

From c7cedc28421ede74484ed42f0a8f0318c5dae743 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 4 Nov 2016 22:05:19 +0000
Subject: [PATCH 07/30] Defined bokeh widget parameters

---
 holoviews/plotting/bokeh/widgets.py | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/holoviews/plotting/bokeh/widgets.py b/holoviews/plotting/bokeh/widgets.py
index e26ed60b60..0b6c69a2f8 100644
--- a/holoviews/plotting/bokeh/widgets.py
+++ b/holoviews/plotting/bokeh/widgets.py
@@ -20,6 +20,15 @@ class BokehServerWidgets(param.Parameterized):
     """
     """
 
+    basejs = param.String(default=None, doc="""
+        Defines the local CSS file to be loaded for this widget.""")
+
+    extensionjs = param.String(default=None, doc="""
+        Optional javascript extension file for a particular backend.""")
+
+    css = param.String(default=None, doc="""
+        Defines the local CSS file to be loaded for this widget.""")
+
     position = param.ObjectSelector(default='right',
         objects=['right', 'left', 'above', 'below'])
 

From 3b43aabfc2139bdb4eb93b1f0622daef183ac686 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 3 Feb 2017 14:08:22 +0000
Subject: [PATCH 08/30] Added bokeh app examples

---
 examples/apps/crossfilter.py      | 78 +++++++++++++++++++++++++++++++
 examples/apps/player.py           | 49 +++++++++++++++++++
 examples/apps/selection_stream.py | 17 +++++++
 3 files changed, 144 insertions(+)
 create mode 100644 examples/apps/crossfilter.py
 create mode 100644 examples/apps/player.py
 create mode 100644 examples/apps/selection_stream.py

diff --git a/examples/apps/crossfilter.py b/examples/apps/crossfilter.py
new file mode 100644
index 0000000000..f9fe0ab3b0
--- /dev/null
+++ b/examples/apps/crossfilter.py
@@ -0,0 +1,78 @@
+import numpy as np
+import pandas as pd
+import holoviews as hv
+import holoviews.plotting.bokeh
+
+from bokeh.layouts import row, widgetbox
+from bokeh.models import Select
+from bokeh.plotting import curdoc, figure
+from bokeh.sampledata.autompg import autompg
+
+df = autompg.copy()
+
+SIZES = list(range(6, 22, 3))
+ORIGINS = ['North America', 'Europe', 'Asia']
+
+# data cleanup
+df.cyl = [str(x) for x in df.cyl]
+df.origin = [ORIGINS[x-1] for x in df.origin]
+
+df['year'] = [str(x) for x in df.yr]
+del df['yr']
+
+df['mfr'] = [x.split()[0] for x in df.name]
+df.loc[df.mfr=='chevy', 'mfr'] = 'chevrolet'
+df.loc[df.mfr=='chevroelt', 'mfr'] = 'chevrolet'
+df.loc[df.mfr=='maxda', 'mfr'] = 'mazda'
+df.loc[df.mfr=='mercedes-benz', 'mfr'] = 'mercedes'
+df.loc[df.mfr=='toyouta', 'mfr'] = 'toyota'
+df.loc[df.mfr=='vokswagen', 'mfr'] = 'volkswagen'
+df.loc[df.mfr=='vw', 'mfr'] = 'volkswagen'
+del df['name']
+
+columns = sorted(df.columns)
+discrete = [x for x in columns if df[x].dtype == object]
+continuous = [x for x in columns if x not in discrete]
+quantileable = [x for x in continuous if len(df[x].unique()) > 20]
+
+hv.Store.current_backend = 'bokeh'
+renderer = hv.Store.renderers['bokeh']
+options = hv.Store.options(backend='bokeh')
+options.Points = hv.Options('plot', width=800, height=600, size_index=None,)
+options.Points = hv.Options('style', cmap='rainbow', line_color='black')
+
+def create_figure():
+    label = "%s vs %s" % (x.value.title(), y.value.title())
+    kdims = [x.value, y.value]
+
+    opts, style = {}, {}
+    opts['color_index'] = color.value if color.value != 'None' else None
+    if size.value != 'None':
+        opts['size_index'] = size.value
+        opts['scaling_factor'] = (1./df[size.value].max())*200
+    points = hv.Points(df, kdims=kdims, label=label)(plot=opts, style=style)
+    plot = renderer.get_plot(points)
+    plot.initialize_plot()
+    return plot.state
+
+def update(attr, old, new):
+    layout.children[1] = create_figure()
+
+
+x = Select(title='X-Axis', value='mpg', options=quantileable)
+x.on_change('value', update)
+
+y = Select(title='Y-Axis', value='hp', options=quantileable)
+y.on_change('value', update)
+
+size = Select(title='Size', value='None', options=['None'] + quantileable)
+size.on_change('value', update)
+
+color = Select(title='Color', value='None', options=['None'] + quantileable)
+color.on_change('value', update)
+
+controls = widgetbox([x, y, color, size], width=200)
+layout = row(controls, create_figure())
+
+curdoc().add_root(layout)
+curdoc().title = "Crossfilter"
diff --git a/examples/apps/player.py b/examples/apps/player.py
new file mode 100644
index 0000000000..800e22a190
--- /dev/null
+++ b/examples/apps/player.py
@@ -0,0 +1,49 @@
+# -*- coding: utf-8 -*-
+import numpy as np
+from bokeh.io import curdoc
+from bokeh.layouts import layout
+from bokeh.models import (
+    ColumnDataSource, HoverTool, SingleIntervalTicker, Slider, Button, Label,
+    CategoricalColorMapper,
+)
+import holoviews as hv
+import holoviews.plotting.bokeh
+
+renderer = hv.Store.renderers['bokeh']
+
+start = 0
+end = 10
+
+hmap = hv.HoloMap({i: hv.Image(np.random.rand(10,10)) for i in range(start, end+1)})
+plot = renderer.get_plot(hmap)
+plot.update(0)
+
+def animate_update():
+    year = slider.value + 1
+    if year > end:
+        year = start
+    slider.value = year
+
+def slider_update(attrname, old, new):
+    plot.update(slider.value)
+
+slider = Slider(start=start, end=end, value=0, step=1, title="Year")
+slider.on_change('value', slider_update)
+
+def animate():
+    if button.label == '► Play':
+        button.label = '❚❚ Pause'
+        curdoc().add_periodic_callback(animate_update, 200)
+    else:
+        button.label = '► Play'
+        curdoc().remove_periodic_callback(animate_update)
+
+button = Button(label='► Play', width=60)
+button.on_click(animate)
+
+layout = layout([
+    [plot.state],
+    [slider, button],
+], sizing_mode='fixed')
+
+curdoc().add_root(layout)
diff --git a/examples/apps/selection_stream.py b/examples/apps/selection_stream.py
new file mode 100644
index 0000000000..5deb34fd7c
--- /dev/null
+++ b/examples/apps/selection_stream.py
@@ -0,0 +1,17 @@
+import numpy as np
+import holoviews as hv
+import holoviews.plotting.bokeh
+from holoviews.streams import Selection1D
+
+hv.Store.current_backend = 'bokeh'
+renderer = hv.Store.renderers['bokeh'].instance(mode='server')
+hv.Store.options(backend='bokeh').Points = hv.Options('plot', tools=['box_select'])
+
+data = np.random.multivariate_normal((0, 0), [[1, 0.1], [0.1, 1]], (1000,))
+points = hv.Points(data)
+sel = Selection1D(source=points)
+mean_sel = hv.DynamicMap(lambda index: hv.HLine(points['y'][index].mean()
+                                                if index else -10),
+                         kdims=[], streams=[sel])
+doc,_ = renderer((points * mean_sel))
+doc.title = 'HoloViews Selection Stream'

From 7697a2a432b9efe8d891a7fe33c9f0af07a248d6 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Sun, 26 Mar 2017 12:51:42 +0100
Subject: [PATCH 09/30] Small fix for bokeh widget import

---
 holoviews/plotting/bokeh/renderer.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/holoviews/plotting/bokeh/renderer.py b/holoviews/plotting/bokeh/renderer.py
index fdc598b869..6821028c1e 100644
--- a/holoviews/plotting/bokeh/renderer.py
+++ b/holoviews/plotting/bokeh/renderer.py
@@ -16,7 +16,7 @@
 from ...core import Store, HoloMap
 from ..comms import JupyterComm, Comm
 from ..renderer import Renderer, MIME_TYPES
-from .widgets import BokehScrubberWidget, BokehSelectionWidget
+from .widgets import BokehScrubberWidget, BokehSelectionWidget, BokehServerWidgets
 from .util import compute_static_patch, serialize_json
 
 

From 27ee5660aef93409bf050f635e9d6386936b3a70 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Sun, 26 Mar 2017 13:19:09 +0100
Subject: [PATCH 10/30] Improved handling of boomeranging events in bokeh
 backend

---
 holoviews/plotting/bokeh/callbacks.py | 16 +++++---------
 holoviews/plotting/bokeh/element.py   | 32 ++++++++++++++++++---------
 2 files changed, 27 insertions(+), 21 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index b5c45c3c8f..eba39f55f2 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -373,22 +373,18 @@ def trigger(self):
             if attr_path[0] == 'cb_obj':
                 attr_path = self.models[0]
             obj = self.plot_handles.get(attr_path[0])
+            attr_val = obj
             if not obj:
                 raise Exception('Bokeh plot attribute %s could not be found' % path)
             for p in attr_path[1:]:
                 if p == 'attributes':
                     continue
-                if isinstance(obj, dict):
-                    obj = obj.get(p)
+                if isinstance(attr_val, dict):
+                    attr_val = attr_val.get(p)
                 else:
-                    obj = getattr(obj, p, None)
-            values[attr] = obj
-        values = self._process_msg(values)
-        if any(v is None for v in values.values()):
-            return
-        for stream in self.streams:
-            stream.update(trigger=False, **values)
-        Stream.trigger(self.streams)
+                    attr_val = getattr(attr_val, p, None)
+            values[attr] = {'id': obj.ref['id'], 'value': attr_val}
+        self.on_msg(values)
         self._event_queue = []
 
 
diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 43e07b6a55..033a3c0a47 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -526,8 +526,10 @@ def _update_ranges(self, element, ranges):
         xfactors, yfactors = None, None
         if any(isinstance(ax_range, FactorRange) for ax_range in [x_range, y_range]):
             xfactors, yfactors = self._get_factors(element)
-        self._update_range(x_range, l, r, xfactors, self.invert_xaxis, self._shared['x'])
-        self._update_range(y_range, b, t, yfactors, self.invert_yaxis, self._shared['y'])
+        if not self.model_changed(x_range):
+            self._update_range(x_range, l, r, xfactors, self.invert_xaxis, self._shared['x'])
+        if not self.model_changed(y_range):
+            self._update_range(y_range, b, t, yfactors, self.invert_yaxis, self._shared['y'])
 
 
     def _update_range(self, axis_range, low, high, factors, invert, shared):
@@ -788,6 +790,21 @@ def update_frame(self, key, ranges=None, plot=None, element=None, empty=False):
         self._execute_hooks(element)
 
 
+    def model_changed(self, model):
+        """
+        Determines if the bokeh model was just changed on the frontend.
+        Useful to suppress boomeranging events, e.g. when the frontend
+        just sent an update to the x_range this should not trigger an
+        update on the backend.
+        """
+        callbacks = [cb for cbs in self.traverse(lambda x: x.callbacks)
+                             for cb in cbs]
+        stream_metadata = [stream._metadata for cb in callbacks
+                           for stream in cb.streams if stream._metadata]
+        return any(md['id'] == model.ref['id'] for models in stream_metadata
+                   for md in models.values())
+
+
     @property
     def current_handles(self):
         """
@@ -821,15 +838,8 @@ def current_handles(self):
             if not self.apply_ranges:
                 rangex, rangey = False, False
             elif isinstance(self.hmap, DynamicMap):
-                callbacks = [cb for cbs in self.traverse(lambda x: x.callbacks)
-                             for cb in cbs]
-                stream_metadata = [stream._metadata for cb in callbacks
-                                   for stream in cb.streams if stream._metadata]
-                ranges = ['%s_range' % ax for ax in 'xy']
-                event_ids = [md[ax]['id'] for md in stream_metadata
-                             for ax in ranges if ax in md]
-                rangex = plot.x_range.ref['id'] not in event_ids and framewise
-                rangey = plot.y_range.ref['id'] not in event_ids and framewise
+                rangex = not self.model_changed(plot.x_range) and framewise
+                rangey = not self.model_changed(plot.y_range) and framewise
             elif self.framewise:
                 rangex, rangey = True, True
             else:

From 78a2c2a4bb27c3f9b5e73f8db29751a936b1e615 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Sun, 26 Mar 2017 17:55:49 +0100
Subject: [PATCH 11/30] Improved bokeh server event queue

---
 holoviews/plotting/bokeh/callbacks.py |  3 ++-
 holoviews/plotting/bokeh/widgets.py   | 17 ++++++++++++++---
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index eba39f55f2..7a202570f4 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -366,6 +366,7 @@ def trigger(self):
         """
         if not self._event_queue:
             return
+        self._event_queue = []
 
         values = {}
         for attr, path in self.attributes.items():
@@ -385,7 +386,7 @@ def trigger(self):
                     attr_val = getattr(attr_val, p, None)
             values[attr] = {'id': obj.ref['id'], 'value': attr_val}
         self.on_msg(values)
-        self._event_queue = []
+        self.plot.document.add_timeout_callback(self.trigger, 50)
 
 
     def set_onchange(self, handle):
diff --git a/holoviews/plotting/bokeh/widgets.py b/holoviews/plotting/bokeh/widgets.py
index 0b6c69a2f8..e50a112d01 100644
--- a/holoviews/plotting/bokeh/widgets.py
+++ b/holoviews/plotting/bokeh/widgets.py
@@ -61,6 +61,7 @@ def __init__(self, plot, renderer=None, **params):
         if self.plot.renderer.mode == 'default':
             self.attach_callbacks()
         self.state = self.init_layout()
+        self._event_queue = []
 
 
     def get_widgets(self):
@@ -106,8 +107,8 @@ def get_widgets(self):
                                     options=list(zip(values, labels)))
                 lookup = zip(values, labels)
             if label:
-                label.on_change('value', partial(self.update, dim.pprint_label, 'label'))
-            widget.on_change('value', partial(self.update, dim.pprint_label, 'widget'))
+                label.on_change('value', partial(self.on_change, dim.pprint_label, 'label'))
+            widget.on_change('value', partial(self.on_change, dim.pprint_label, 'widget'))
             widgets[dim.pprint_label] = (label, widget)
             if lookup:
                 lookups[dim.pprint_label] = OrderedDict(lookup)
@@ -134,10 +135,20 @@ def attach_callbacks(self):
         pass
 
 
-    def update(self, dim, widget_type, attr, old, new):
+    def on_change(self, dim, widget_type, attr, old, new):
+        self._event_queue.append((dim, widget_type, attr, old, new))
+        if self.update not in self.plot.document._session_callbacks:
+            self.plot.document.add_timeout_callback(self.update, 50)
+
+
+    def update(self):
         """
         Handle update events on bokeh server.
         """
+        if not self._event_queue:
+            return
+        dim, widget_type, attr, old, new = self._event_queue[-1]
+
         label, widget = self.widgets[dim]
         if widget_type == 'label':
             if isinstance(label, AutocompleteInput):

From c32e2ab155bf3dbcec2e57bb19e1d06870f6679c Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Sun, 26 Mar 2017 18:19:44 +0100
Subject: [PATCH 12/30] Improved range updates for bokeh server

---
 holoviews/plotting/bokeh/element.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/holoviews/plotting/bokeh/element.py b/holoviews/plotting/bokeh/element.py
index 033a3c0a47..375e175d9d 100644
--- a/holoviews/plotting/bokeh/element.py
+++ b/holoviews/plotting/bokeh/element.py
@@ -526,9 +526,10 @@ def _update_ranges(self, element, ranges):
         xfactors, yfactors = None, None
         if any(isinstance(ax_range, FactorRange) for ax_range in [x_range, y_range]):
             xfactors, yfactors = self._get_factors(element)
-        if not self.model_changed(x_range):
+        framewise = self.framewise
+        if not self.drawn or (not self.model_changed(x_range) and framewise):
             self._update_range(x_range, l, r, xfactors, self.invert_xaxis, self._shared['x'])
-        if not self.model_changed(y_range):
+        if not self.drawn or (not self.model_changed(y_range) and framewise):
             self._update_range(y_range, b, t, yfactors, self.invert_yaxis, self._shared['y'])
 
 

From 3f0dca8635b4cb07751fa06cde6c56d8650bc5d6 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Sun, 26 Mar 2017 22:15:28 +0100
Subject: [PATCH 13/30] Fixed small bugs in bokeh Callbacks

---
 holoviews/plotting/bokeh/callbacks.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index 7a202570f4..e95e472bcc 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -276,7 +276,7 @@ def initialize(self):
                     continue
 
                 if self.plot.renderer.mode == 'server':
-                    self.set_onchange(plot.handles[handle_name])
+                    self.set_onchange(handle)
                 else:
                     js_callback = self.get_customjs(requested)
                     self.set_customjs(js_callback, handle)
@@ -401,7 +401,7 @@ def set_onchange(self, handle):
                 handle.on_change(change, self.on_change)
 
 
-    def set_customjs(self, handle, references):
+    def get_customjs(self, references):
         """
         Creates a CustomJS callback that will send the requested
         attributes back to python.
@@ -427,8 +427,6 @@ def set_customjs(self, js_callback, handle):
         code and gathering all plotting handles and installs it on
         the requested callback handle.
         """
-
-        self._callbacks[cb_hash] = self
         if self.events and bokeh_version >= '0.12.5':
             for event in self.events:
                 handle.js_on_event(event, js_callback)

From 9bf098266391575fafd189a11b881e5fa38cff6c Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 13:54:05 +0100
Subject: [PATCH 14/30] Fixed bokeh event callbacks after change to cb_obj

---
 holoviews/plotting/bokeh/callbacks.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index e95e472bcc..337bd1d6a0 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -187,7 +187,7 @@ class Callback(object):
         }}
 
         // Add current event to queue and process queue if not blocked
-        event_name = cb_obj.event ? cb_obj.event.event_name : undefined
+        event_name = cb_obj.event_name
         data['comm_id'] = "{comm_id}";
         timeout = comm_state.time + {timeout};
         if ((window.Jupyter == undefined) | (Jupyter.notebook.kernel == undefined)) {{
@@ -444,7 +444,7 @@ class PositionXYCallback(Callback):
     Returns the mouse x/y-position on mousemove event.
     """
 
-    attributes = {'x': 'cb_obj.event.x', 'y': 'cb_obj.event.y'}
+    attributes = {'x': 'cb_obj.x', 'y': 'cb_obj.y'}
     models = ['plot']
     events = ['mousemove']
 
@@ -454,7 +454,7 @@ class PositionXCallback(PositionXYCallback):
     Returns the mouse x-position on mousemove event.
     """
 
-    attributes = {'x': 'cb_obj.event.x'}
+    attributes = {'x': 'cb_obj.x'}
 
 
 class PositionYCallback(PositionXYCallback):
@@ -462,7 +462,7 @@ class PositionYCallback(PositionXYCallback):
     Returns the mouse x/y-position on mousemove event.
     """
 
-    attributes = {'y': 'cb_data.event.y'}
+    attributes = {'y': 'cb_data.y'}
 
 
 class TapCallback(PositionXYCallback):

From b099b7e800a64d782f9b12b34d33214063f30ec8 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 14:22:06 +0100
Subject: [PATCH 15/30] Implemented UIEvent handling for bokeh server

---
 holoviews/plotting/bokeh/callbacks.py | 28 ++++++++++++++++++++++-----
 1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index 337bd1d6a0..0f09568739 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -360,20 +360,37 @@ def on_change(self, attr, old, new):
             self.plot.document.add_timeout_callback(self.trigger, 50)
 
 
+    def on_event(self, event):
+        """
+        Process bokeh UIEvents adding timeout to process multiple concerted
+        value change at once rather than firing off multiple plot updates.
+        """
+        self._event_queue.append((event))
+        if self.trigger not in self.plot.document._session_callbacks:
+            self.plot.document.add_timeout_callback(self.trigger, 50)
+
+
     def trigger(self):
         """
         Trigger callback change event and triggering corresponding streams.
         """
         if not self._event_queue:
             return
+        if self.events:
+            event = self._event_queue[-1]
         self._event_queue = []
 
         values = {}
         for attr, path in self.attributes.items():
             attr_path = path.split('.')
-            if attr_path[0] == 'cb_obj':
-                attr_path = self.models[0]
-            obj = self.plot_handles.get(attr_path[0])
+            if self.events:
+                obj = event
+                model_obj = self.plot_handles.get(self.models[0])
+            else:
+                if attr_path[0] == 'cb_obj':
+                    attr_path = self.models[:1]+attr_path[1:]
+                obj = self.plot_handles.get(attr_path[0])
+                model_obj = obj
             attr_val = obj
             if not obj:
                 raise Exception('Bokeh plot attribute %s could not be found' % path)
@@ -384,7 +401,8 @@ def trigger(self):
                     attr_val = attr_val.get(p)
                 else:
                     attr_val = getattr(attr_val, p, None)
-            values[attr] = {'id': obj.ref['id'], 'value': attr_val}
+            values[attr] = {'id': model_obj.ref['id'],
+                            'value': attr_val}
         self.on_msg(values)
         self.plot.document.add_timeout_callback(self.trigger, 50)
 
@@ -395,7 +413,7 @@ def set_onchange(self, handle):
         """
         if self.events and bokeh_version >= '0.12.5':
             for event in self.events:
-                handle.on_event(event, self.on_change)
+                handle.on_event(event, self.on_event)
         elif self.change:
             for change in self.change:
                 handle.on_change(change, self.on_change)

From dbef691b82d822b0164a188224ceb65bf4e67d9b Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 14:57:34 +0100
Subject: [PATCH 16/30] Moved bokeh server example apps

---
 .../plotting/bokeh/examples/apps}/apps/crossfilter.py             | 0
 .../plotting/bokeh/examples/apps}/apps/player.py                  | 0
 .../plotting/bokeh/examples/apps}/apps/selection_stream.py        | 0
 3 files changed, 0 insertions(+), 0 deletions(-)
 rename {examples => holoviews/plotting/bokeh/examples/apps}/apps/crossfilter.py (100%)
 rename {examples => holoviews/plotting/bokeh/examples/apps}/apps/player.py (100%)
 rename {examples => holoviews/plotting/bokeh/examples/apps}/apps/selection_stream.py (100%)

diff --git a/examples/apps/crossfilter.py b/holoviews/plotting/bokeh/examples/apps/apps/crossfilter.py
similarity index 100%
rename from examples/apps/crossfilter.py
rename to holoviews/plotting/bokeh/examples/apps/apps/crossfilter.py
diff --git a/examples/apps/player.py b/holoviews/plotting/bokeh/examples/apps/apps/player.py
similarity index 100%
rename from examples/apps/player.py
rename to holoviews/plotting/bokeh/examples/apps/apps/player.py
diff --git a/examples/apps/selection_stream.py b/holoviews/plotting/bokeh/examples/apps/apps/selection_stream.py
similarity index 100%
rename from examples/apps/selection_stream.py
rename to holoviews/plotting/bokeh/examples/apps/apps/selection_stream.py

From 2e9ca718b06469e3b356fb36baf1617da859aa6b Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 17:40:29 +0100
Subject: [PATCH 17/30] Completely refactored bokeh Callbacks

---
 holoviews/plotting/bokeh/callbacks.py | 561 ++++++++++++++------------
 1 file changed, 304 insertions(+), 257 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index 0f09568739..22d04c5380 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -4,6 +4,7 @@
 import numpy as np
 from bokeh.models import CustomJS
 
+from ...core import OrderedDict
 from ...streams import (Stream, PositionXY, RangeXY, Selection1D, RangeX,
                         RangeY, PositionX, PositionY, Bounds, Tap,
                         DoubleTap, MouseEnter, MouseLeave, PlotSize)
@@ -52,67 +53,139 @@ def attributes_js(attributes, handles):
     return code
 
 
-class Callback(object):
+def resolve_attr_spec(spec, cb_obj, model):
     """
-    Provides a baseclass to define callbacks, which return data from
-    bokeh model callbacks, events and attribute changes. The callback
-    then makes this data available to any streams attached to it.
+    Resolves a Callback attribute specification looking the
+    corresponding attribute up on the cb_obj, which should be a bokeh
+    model.
+    """
+    if not cb_obj:
+        raise Exception('Bokeh plot attribute %s could not be found' % spec)
+    spec = spec.split('.')
+    resolved = cb_obj
+    for p in spec[1:]:
+        if p == 'attributes':
+            continue
+        if isinstance(resolved, dict):
+            resolved = resolved.get(p)
+        else:
+            resolved = getattr(resolved, p, None)
+    return {'id': model.ref['id'], 'value': resolved}
 
-    The definition of a callback consists of a number of components:
 
-    * models      : Defines which bokeh models the callback will be
-                    attached on referencing the model by its key in
-                    the plots handles, e.g. this could be the x_range,
-                    y_range, plot, a plotting tool or any other
-                    bokeh mode.
 
-    * extra_models: Any additional models available in handles which
-                    should be made available in the namespace of the
-                    objects, e.g. to make a tool available to skip
-                    checks.
+class MessageCallback(object):
+    """
+    A MessageCallback is an abstract baseclass used to supply Streams
+    with events originating from bokeh plot interactions. The baseclass
+    defines how messages are handled and the basic specification required
+    to define a Callback.
+    """
 
-    * attributes  : The attributes define which attributes to send
-                    back to Python. They are defined as a dictionary
-                    mapping between the name under which the variable
-                    is made available to Python and the specification
-                    of the attribute. The specification should start
-                    with the variable name that is to be accessed and
-                    the location of the attribute separated by
-                    periods.  All models defined by the models and
-                    extra_models attributes can be addressed in this
-                    way, e.g. to get the start of the x_range as 'x'
-                    you can supply {'x': 'x_range.attributes.start'}.
-                    Additionally certain handles additionally make the
-                    cb_data and cb_obj variables available containing
-                    additional information about the event.
+    attributes = {}
 
-    * skip        : Conditions when the Callback should be skipped
-                    specified as a list of valid JS expressions, which
-                    can reference models requested by the callback,
-                    e.g. ['pan.attributes.active'] would skip the
-                    callback if the pan tool is active.
+    # The plotting handle(s) to attach the JS callback on
+    models = []
 
-    * code        : Defines any additional JS code to be executed,
-                    which can modify the data object that is sent to
-                    the backend.
+    # Additional models available to the callback
+    extra_models = []
 
-    * events      : If the Callback should listen to bokeh events this
-                    should declare the types of event as a list (optional)
+    # Conditions when callback should be skipped
+    skip = []
 
-    * change      : If the Callback should listen to model attribute
-                    changes on the defined ``models`` (optional)
+    # Callback will listen to events of the supplied type on the models
+    on_events = []
 
-    If either the event or change attributes are declared the Callback
-    will be registered using the on_event or on_change machinery,
-    otherwise it will be treated as a regular callback on the model.
-    The callback can also define a _process_msg method, which can
-    modify the data sent by the callback before it is passed to the
-    streams.
-    """
+    # List of change events on the models to listen to
+    on_change = []
 
-    code = ""
+    _callbacks = {}
 
-    attributes = {}
+    def _process_msg(self, msg):
+        """
+        Subclassable method to preprocess JSON message in callback
+        before passing to stream.
+        """
+        return msg
+
+
+    def __init__(self, plot, streams, source, **params):
+        self.plot = plot
+        self.streams = streams
+        if plot.renderer.mode != 'server':
+            self.comm = self._comm_type(plot, on_msg=self.on_msg)
+        self.source = source
+        self.handle_ids = defaultdict(dict)
+        self.callbacks = []
+        self.plot_handles = {}
+        self._queue = []
+
+
+    def _filter_msg(self, msg, ids):
+        """
+        Filter event values that do not originate from the plotting
+        handles associated with a particular stream using their
+        ids to match them.
+        """
+        filtered_msg = {}
+        for k, v in msg.items():
+            if isinstance(v, dict) and 'id' in v:
+                if v['id'] in ids:
+                    filtered_msg[k] = v['value']
+            else:
+                filtered_msg[k] = v
+        return filtered_msg
+
+
+    def on_msg(self, msg):
+        for stream in self.streams:
+            handle_ids = self.handle_ids[stream]
+            ids = list(handle_ids.values())
+            filtered_msg = self._filter_msg(msg, ids)
+            processed_msg = self._process_msg(filtered_msg)
+            if not processed_msg:
+                continue
+            stream.update(trigger=False, **processed_msg)
+            stream._metadata = {h: {'id': hid, 'events': self.on_events}
+                                for h, hid in handle_ids.items()}
+        Stream.trigger(self.streams)
+        for stream in self.streams:
+            stream._metadata = {}
+
+
+    def _get_plot_handles(self, plots):
+        """
+        Iterate over plots and find all unique plotting handles.
+        """
+        handles = {}
+        for plot in plots:
+            for k, v in plot.handles.items():
+                handles[k] = v
+        return handles
+
+
+    def _get_stream_handle_ids(self, handles):
+        """
+        Gather the ids of the plotting handles attached to this callback
+        This allows checking that a stream is not given the state
+        of a plotting handle it wasn't attached to
+        """
+        stream_handle_ids = defaultdict(dict)
+        for stream in self.streams:
+            for h in self.models:
+                if h in handles:
+                    handle_id = handles[h].ref['id']
+                    stream_handle_ids[stream][h] = handle_id
+        return stream_handle_ids
+
+
+
+class CustomJSCallback(MessageCallback):
+    """
+    The CustomJSCallback attaches CustomJS callbacks to a bokeh plot,
+    which looks up the requested attributes and sends back a message
+    to Python using a Comms instance.
+    """
 
     js_callback = """
         function unique_events(events) {{
@@ -201,22 +274,7 @@ class Callback(object):
         }}
     """
 
-    # The plotting handle(s) to attach the JS callback on
-    models = []
-
-    # Additional models available to the callback
-    extra_models = []
-
-    # Conditions when callback should be skipped
-    skip = []
-
-    # Callback will listen to events of the supplied type on the models
-    events = []
-
-    # List of attributes on the models to listen to
-    change = []
-
-    _comm_type = JupyterCommJS
+    code = ""
 
     # Timeout if a comm message is swallowed
     timeout = 20000
@@ -224,140 +282,61 @@ class Callback(object):
     # Timeout before the first event is processed
     debounce = 20
 
-    _callbacks = {}
-
-    def __init__(self, plot, streams, source, **params):
-        self.plot = plot
-        self.streams = streams
-        if plot.renderer.mode != 'server':
-            self.comm = self._comm_type(plot, on_msg=self.on_msg)
-        self.source = source
-        self.handle_ids = defaultdict(dict)
-        self.callbacks = []
-        self.plot_handles = {}
-        self._event_queue = []
-
-
-    def initialize(self):
-        plots = [self.plot]
-        if self.plot.subplots:
-            plots += list(self.plot.subplots.values())
-
-        self.plot_handles = self._get_plot_handles(plots)
-        requested = {}
-        for h in self.models+self.extra_models:
-            if h in self.plot_handles:
-                requested[h] = self.plot_handles[h]
-            elif h in self.extra_models:
-                print("Warning %s could not find the %s model. "
-                      "The corresponding stream may not work.")
-        self.handle_ids.update(self._get_stream_handle_ids(requested))
-
-        found = []
-        for plot in plots:
-            for handle_name in self.models:
-                if handle_name not in self.plot_handles:
-                    warn_args = (handle_name, type(self.plot).__name__,
-                                 type(self).__name__)
-                    print('%s handle not found on %s, cannot '
-                          'attach %s callback' % warn_args)
-                    continue
-                handle = self.plot_handles[handle_name]
-
-                # Hash the plot handle with Callback type allowing multiple
-                # callbacks on one handle to be merged
-                cb_hash = (id(handle), id(type(self)))
-                if cb_hash in self._callbacks:
-                    # Merge callbacks if another callback has already been attached
-                    cb = self._callbacks[cb_hash]
-                    cb.streams += self.streams
-                    for k, v in self.handle_ids.items():
-                        cb.handle_ids[k].update(v)
-                    continue
-
-                if self.plot.renderer.mode == 'server':
-                    self.set_onchange(handle)
-                else:
-                    js_callback = self.get_customjs(requested)
-                    self.set_customjs(js_callback, handle)
-                    self.callbacks.append(js_callback)
-                self._callbacks[cb_hash] = self
-
+    _comm_type = JupyterCommJS
 
-    def _filter_msg(self, msg, ids):
+    def get_customjs(self, references):
         """
-        Filter event values that do not originate from the plotting
-        handles associated with a particular stream using their
-        ids to match them.
+        Creates a CustomJS callback that will send the requested
+        attributes back to python.
         """
-        filtered_msg = {}
-        for k, v in msg.items():
-            if isinstance(v, dict) and 'id' in v:
-                if v['id'] in ids:
-                    filtered_msg[k] = v['value']
-            else:
-                filtered_msg[k] = v
-        return filtered_msg
-    
-
-    def on_msg(self, msg):
-        for stream in self.streams:
-            handle_ids = self.handle_ids[stream]
-            ids = list(handle_ids.values())
-            filtered_msg = self._filter_msg(msg, ids)
-            processed_msg = self._process_msg(filtered_msg)
-            if not processed_msg:
-                continue
-            stream.update(trigger=False, **processed_msg)
-            stream._metadata = {h: {'id': hid, 'events': self.events}
-                                for h, hid in handle_ids.items()}
-        Stream.trigger(self.streams)
-        for stream in self.streams:
-            stream._metadata = {}
-
+        # Generate callback JS code to get all the requested data
+        self_callback = self.js_callback.format(comm_id=self.comm.id,
+                                                timeout=self.timeout,
+                                                debounce=self.debounce)
 
-    def _process_msg(self, msg):
-        """
-        Subclassable method to preprocess JSON message in callback
-        before passing to stream.
-        """
-        return msg
+        attributes = attributes_js(self.attributes, references)
+        conditions = ["%s" % cond for cond in self.skip]
+        conditional = ''
+        if conditions:
+            conditional = 'if (%s) { return };\n' % (' || '.join(conditions))
+        data = "var data = {};\n"
+        code = conditional + data + attributes + self.code + self_callback
+        return CustomJS(args=references, code=code)
 
 
-    def _get_plot_handles(self, plots):
+    def set_customjs_callback(self, js_callback, handle):
         """
-        Iterate over plots and find all unique plotting handles.
+        Generates a CustomJS callback by generating the required JS
+        code and gathering all plotting handles and installs it on
+        the requested callback handle.
         """
-        handles = {}
-        for plot in plots:
-            for k, v in plot.handles.items():
-                handles[k] = v
-        return handles
+        if self.on_events and bokeh_version >= '0.12.5':
+            for event in self.on_events:
+                handle.js_on_event(event, js_callback)
+        elif self.on_changes:
+            for change in self.on_changes:
+                handle.js_on_change(change, js_callback)
+        elif hasattr(handle, 'callback'):
+            handle.callback = js_callback
 
 
-    def _get_stream_handle_ids(self, handles):
-        """
-        Gather the ids of the plotting handles attached to this callback
-        This allows checking that a stream is not given the state
-        of a plotting handle it wasn't attached to
-        """
-        stream_handle_ids = defaultdict(dict)
-        for stream in self.streams:
-            for h in self.models:
-                if h in handles:
-                    handle_id = handles[h].ref['id']
-                    stream_handle_ids[stream][h] = handle_id
-        return stream_handle_ids
 
+class ServerCallback(MessageCallback):
+    """
+    Implements methods to set up bokeh server callbacks. A ServerCallback
+    resolves the requested attributes on the Python end and then hands
+    the msg off to the general on_msg handler, which will update the
+    Stream(s) attached to the callback.
+    """
 
     def on_change(self, attr, old, new):
         """
         Process change events adding timeout to process multiple concerted
         value change at once rather than firing off multiple plot updates.
         """
-        self._event_queue.append((attr, old, new))
-        if self.trigger not in self.plot.document._session_callbacks:
-            self.plot.document.add_timeout_callback(self.trigger, 50)
+        self._queue.append((attr, old, new))
+        if self.process_on_change not in self.plot.document._session_callbacks:
+            self.plot.document.add_timeout_callback(self.process_on_change, 50)
 
 
     def on_event(self, event):
@@ -365,95 +344,163 @@ def on_event(self, event):
         Process bokeh UIEvents adding timeout to process multiple concerted
         value change at once rather than firing off multiple plot updates.
         """
-        self._event_queue.append((event))
-        if self.trigger not in self.plot.document._session_callbacks:
-            self.plot.document.add_timeout_callback(self.trigger, 50)
+        self._queue.append((event))
+        if self.process_on_event not in self.plot.document._session_callbacks:
+            self.plot.document.add_timeout_callback(self.process_on_event, 50)
 
 
-    def trigger(self):
+    def process_on_event(self):
         """
         Trigger callback change event and triggering corresponding streams.
         """
-        if not self._event_queue:
+        if not self._queue:
             return
-        if self.events:
-            event = self._event_queue[-1]
-        self._event_queue = []
+        # Get unique event types in the queue
+        events = list(OrderedDict([(event.event_name, event)
+                                   for event in self._queue]).values())
+        self._queue = []
+
+        # Process event types
+        for event in events:
+            msg = {}
+            for attr, path in self.attributes.items():
+                model_obj = self.plot_handles.get(self.models[0])
+                msg[attr] = resolve_attr_spec(path, event, model_obj)
+            self.on_msg(msg)
+        self.plot.document.add_timeout_callback(self.process_on_event, 50)
+
 
-        values = {}
+    def process_on_change(self):
+        if not self._queue:
+            return
+        self._queue = []
+
+        msg = {}
         for attr, path in self.attributes.items():
             attr_path = path.split('.')
-            if self.events:
-                obj = event
-                model_obj = self.plot_handles.get(self.models[0])
-            else:
-                if attr_path[0] == 'cb_obj':
-                    attr_path = self.models[:1]+attr_path[1:]
-                obj = self.plot_handles.get(attr_path[0])
-                model_obj = obj
-            attr_val = obj
-            if not obj:
-                raise Exception('Bokeh plot attribute %s could not be found' % path)
-            for p in attr_path[1:]:
-                if p == 'attributes':
-                    continue
-                if isinstance(attr_val, dict):
-                    attr_val = attr_val.get(p)
-                else:
-                    attr_val = getattr(attr_val, p, None)
-            values[attr] = {'id': model_obj.ref['id'],
-                            'value': attr_val}
-        self.on_msg(values)
-        self.plot.document.add_timeout_callback(self.trigger, 50)
+            if attr_path[0] == 'cb_obj':
+                path = '.'.join(self.models[:1]+attr_path[1:])
+            cb_obj = self.plot_handles.get(self.models[0])
+            msg[attr] = resolve_attr_spec(path, cb_obj, cb_obj)
 
+        self.on_msg(msg)
+        self.plot.document.add_timeout_callback(self.process_on_change, 50)
 
-    def set_onchange(self, handle):
+
+    def set_server_callback(self, handle):
         """
         Set up on_change events for bokeh server interactions.
         """
-        if self.events and bokeh_version >= '0.12.5':
-            for event in self.events:
+        if self.on_events and bokeh_version >= '0.12.5':
+            for event in self.on_events:
                 handle.on_event(event, self.on_event)
-        elif self.change:
-            for change in self.change:
+        elif self.on_changes:
+            for change in self.on_changes:
                 handle.on_change(change, self.on_change)
 
 
-    def get_customjs(self, references):
-        """
-        Creates a CustomJS callback that will send the requested
-        attributes back to python.
-        """
-        # Generate callback JS code to get all the requested data
-        self_callback = self.js_callback.format(comm_id=self.comm.id,
-                                                timeout=self.timeout,
-                                                debounce=self.debounce)
 
-        attributes = attributes_js(self.attributes, references)
-        conditions = ["%s" % cond for cond in self.skip]
-        conditional = ''
-        if conditions:
-            conditional = 'if (%s) { return };\n' % (' || '.join(conditions))
-        data = "var data = {};\n"
-        code = conditional + data + attributes + self.code + self_callback
-        return CustomJS(args=references, code=code)
+class Callback(CustomJSCallback, ServerCallback):
+    """
+    Provides a baseclass to define callbacks, which return data from
+    bokeh model callbacks, events and attribute changes. The callback
+    then makes this data available to any streams attached to it.
 
+    The definition of a callback consists of a number of components:
 
-    def set_customjs(self, js_callback, handle):
-        """
-        Generates a CustomJS callback by generating the required JS
-        code and gathering all plotting handles and installs it on
-        the requested callback handle.
-        """
-        if self.events and bokeh_version >= '0.12.5':
-            for event in self.events:
-                handle.js_on_event(event, js_callback)
-        elif self.change:
-            for change in self.change:
-                handle.js_on_change(change, js_callback)
-        elif hasattr(handle, 'callback'):
-            handle.callback = js_callback
+    * models      : Defines which bokeh models the callback will be
+                    attached on referencing the model by its key in
+                    the plots handles, e.g. this could be the x_range,
+                    y_range, plot, a plotting tool or any other
+                    bokeh mode.
+
+    * extra_models: Any additional models available in handles which
+                    should be made available in the namespace of the
+                    objects, e.g. to make a tool available to skip
+                    checks.
+
+    * attributes  : The attributes define which attributes to send
+                    back to Python. They are defined as a dictionary
+                    mapping between the name under which the variable
+                    is made available to Python and the specification
+                    of the attribute. The specification should start
+                    with the variable name that is to be accessed and
+                    the location of the attribute separated by
+                    periods.  All models defined by the models and
+                    extra_models attributes can be addressed in this
+                    way, e.g. to get the start of the x_range as 'x'
+                    you can supply {'x': 'x_range.attributes.start'}.
+                    Additionally certain handles additionally make the
+                    cb_data and cb_obj variables available containing
+                    additional information about the event.
+
+    * skip        : Conditions when the Callback should be skipped
+                    specified as a list of valid JS expressions, which
+                    can reference models requested by the callback,
+                    e.g. ['pan.attributes.active'] would skip the
+                    callback if the pan tool is active.
+
+    * code        : Defines any additional JS code to be executed,
+                    which can modify the data object that is sent to
+                    the backend.
+
+    * on_events   : If the Callback should listen to bokeh events this
+                    should declare the types of event as a list (optional)
+
+    * on_changes  : If the Callback should listen to model attribute
+                    changes on the defined ``models`` (optional)
+
+    If either on_events or on_changes are declared the Callback will
+    be registered using the on_event or on_change machinery, otherwise
+    it will be treated as a regular callback on the model.  The
+    callback can also define a _process_msg method, which can modify
+    the data sent by the callback before it is passed to the streams.
+    """
+
+    def initialize(self):
+        plots = [self.plot]
+        if self.plot.subplots:
+            plots += list(self.plot.subplots.values())
+
+        self.plot_handles = self._get_plot_handles(plots)
+        requested = {}
+        for h in self.models+self.extra_models:
+            if h in self.plot_handles:
+                requested[h] = self.plot_handles[h]
+            elif h in self.extra_models:
+                print("Warning %s could not find the %s model. "
+                      "The corresponding stream may not work.")
+        self.handle_ids.update(self._get_stream_handle_ids(requested))
+
+        found = []
+        for plot in plots:
+            for handle_name in self.models:
+                if handle_name not in self.plot_handles:
+                    warn_args = (handle_name, type(self.plot).__name__,
+                                 type(self).__name__)
+                    print('%s handle not found on %s, cannot '
+                          'attach %s callback' % warn_args)
+                    continue
+                handle = self.plot_handles[handle_name]
 
+                # Hash the plot handle with Callback type allowing multiple
+                # callbacks on one handle to be merged
+                cb_hash = (id(handle), id(type(self)))
+                if cb_hash in self._callbacks:
+                    # Merge callbacks if another callback has already been attached
+                    cb = self._callbacks[cb_hash]
+                    cb.streams += self.streams
+                    for k, v in self.handle_ids.items():
+                        cb.handle_ids[k].update(v)
+                    continue
+
+                if self.plot.renderer.mode == 'server':
+                    self.set_server_callback(handle)
+                else:
+                    js_callback = self.get_customjs(requested)
+                    self.set_customjs_callback(js_callback, handle)
+                    self.callbacks.append(js_callback)
+                self._callbacks[cb_hash] = self
 
 
 
@@ -464,7 +511,7 @@ class PositionXYCallback(Callback):
 
     attributes = {'x': 'cb_obj.x', 'y': 'cb_obj.y'}
     models = ['plot']
-    events = ['mousemove']
+    on_events = ['mousemove']
 
 
 class PositionXCallback(PositionXYCallback):
@@ -488,7 +535,7 @@ class TapCallback(PositionXYCallback):
     Returns the mouse x/y-position on tap event.
     """
 
-    events = ['tap']
+    on_events = ['tap']
 
 
 class DoubleTapCallback(PositionXYCallback):
@@ -496,7 +543,7 @@ class DoubleTapCallback(PositionXYCallback):
     Returns the mouse x/y-position on doubletap event.
     """
 
-    events = ['doubletap']
+    on_events = ['doubletap']
 
 
 class MouseEnterCallback(PositionXYCallback):
@@ -505,7 +552,7 @@ class MouseEnterCallback(PositionXYCallback):
     mouse enters the plot canvas.
     """
 
-    events = ['mouseenter']
+    on_events = ['mouseenter']
 
 
 class MouseLeaveCallback(PositionXYCallback):
@@ -514,7 +561,7 @@ class MouseLeaveCallback(PositionXYCallback):
     mouse leaves the plot canvas.
     """
 
-    events = ['mouseleave']
+    on_events = ['mouseleave']
 
 
 class RangeXYCallback(Callback):
@@ -527,7 +574,7 @@ class RangeXYCallback(Callback):
                   'y0': 'y_range.attributes.start',
                   'y1': 'y_range.attributes.end'}
     models = ['x_range', 'y_range']
-    change = ['start', 'end']
+    on_changes = ['start', 'end']
 
     def _process_msg(self, msg):
         data = {}
@@ -579,7 +626,7 @@ class PlotSizeCallback(Callback):
     models = ['plot']
     attributes = {'width': 'cb_obj.inner_width',
                   'height': 'cb_obj.inner_height'}
-    change = ['inner_width', 'inner_height']
+    on_changes = ['inner_width', 'inner_height']
 
 
 class BoundsCallback(Callback):
@@ -607,7 +654,7 @@ class Selection1DCallback(Callback):
 
     attributes = {'index': 'cb_obj.selected.1d.indices'}
     models = ['source']
-    change = ['selected']
+    on_changes = ['selected']
 
     def _process_msg(self, msg):
         if 'index' in msg:

From d7f5e45ad5ca122cf95ae08676fe5c9056c958e3 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 19:02:12 +0100
Subject: [PATCH 18/30] Made callback utilities into classmethods

---
 holoviews/plotting/bokeh/callbacks.py | 132 +++++++++++++-------------
 1 file changed, 68 insertions(+), 64 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index 22d04c5380..aa0ca02ddb 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -12,67 +12,6 @@
 from .util import bokeh_version
 
 
-def attributes_js(attributes, handles):
-    """
-    Generates JS code to look up attributes on JS objects from
-    an attributes specification dictionary. If the specification
-    references a plotting particular plotting handle it will also
-    generate JS code to get the ID of the object.
-
-    Simple example (when referencing cb_data or cb_obj):
-
-    Input  : {'x': 'cb_data.geometry.x'}
-
-    Output : data['x'] = cb_data['geometry']['x']
-
-    Example referencing plot handle:
-
-    Input  : {'x0': 'x_range.attributes.start'}
-
-    Output : if ((x_range !== undefined)) {
-               data['x0'] = {id: x_range['id'], value: x_range['attributes']['start']}
-             }
-    """
-    code = ''
-    for key, attr_path in attributes.items():
-        data_assign = "data['{key}'] = ".format(key=key)
-        attrs = attr_path.split('.')
-        obj_name = attrs[0]
-        attr_getters = ''.join(["['{attr}']".format(attr=attr)
-                                for attr in attrs[1:]])
-        if obj_name not in ['cb_obj', 'cb_data']:
-            assign_str = '{assign}{{id: {obj_name}["id"], value: {obj_name}{attr_getters}}};\n'.format(
-                assign=data_assign, obj_name=obj_name, attr_getters=attr_getters
-            )
-            code += 'if (({obj_name} != undefined)) {{ {assign} }}'.format(
-                obj_name=obj_name, id=handles[obj_name].ref['id'], assign=assign_str
-                )
-        else:
-            assign_str = ''.join([data_assign, obj_name, attr_getters, ';\n'])
-            code += assign_str
-    return code
-
-
-def resolve_attr_spec(spec, cb_obj, model):
-    """
-    Resolves a Callback attribute specification looking the
-    corresponding attribute up on the cb_obj, which should be a bokeh
-    model.
-    """
-    if not cb_obj:
-        raise Exception('Bokeh plot attribute %s could not be found' % spec)
-    spec = spec.split('.')
-    resolved = cb_obj
-    for p in spec[1:]:
-        if p == 'attributes':
-            continue
-        if isinstance(resolved, dict):
-            resolved = resolved.get(p)
-        else:
-            resolved = getattr(resolved, p, None)
-    return {'id': model.ref['id'], 'value': resolved}
-
-
 
 class MessageCallback(object):
     """
@@ -284,6 +223,50 @@ class CustomJSCallback(MessageCallback):
 
     _comm_type = JupyterCommJS
 
+    @classmethod
+    def attributes_js(cls, attributes, handles):
+        """
+        Generates JS code to look up attributes on JS objects from
+        an attributes specification dictionary. If the specification
+        references a plotting particular plotting handle it will also
+        generate JS code to get the ID of the object.
+
+        Simple example (when referencing cb_data or cb_obj):
+
+        Input  : {'x': 'cb_data.geometry.x'}
+
+        Output : data['x'] = cb_data['geometry']['x']
+
+        Example referencing plot handle:
+
+        Input  : {'x0': 'x_range.attributes.start'}
+
+        Output : if ((x_range !== undefined)) {
+                    data['x0'] = {id: x_range['id'], value: x_range['attributes']['start']}
+                 }
+        """
+        assign_template = '{assign}{{id: {obj_name}["id"], value: {obj_name}{attr_getters}}};\n'
+        conditional_template = 'if (({obj_name} != undefined)) {{ {assign} }}'
+        code = ''
+        for key, attr_path in attributes.items():
+            data_assign = "data['{key}'] = ".format(key=key)
+            attrs = attr_path.split('.')
+            obj_name = attrs[0]
+            attr_getters = ''.join(["['{attr}']".format(attr=attr)
+                                    for attr in attrs[1:]])
+            if obj_name not in ['cb_obj', 'cb_data']:
+                assign_str = assign_template.format(
+                    assign=data_assign, obj_name=obj_name, attr_getters=attr_getters
+                )
+                code += conditional_template.format(
+                    obj_name=obj_name, id=handles[obj_name].ref['id'], assign=assign_str
+                )
+            else:
+                assign_str = ''.join([data_assign, obj_name, attr_getters, ';\n'])
+                code += assign_str
+        return code
+
+
     def get_customjs(self, references):
         """
         Creates a CustomJS callback that will send the requested
@@ -294,7 +277,7 @@ def get_customjs(self, references):
                                                 timeout=self.timeout,
                                                 debounce=self.debounce)
 
-        attributes = attributes_js(self.attributes, references)
+        attributes = self.attributes_js(self.attributes, references)
         conditions = ["%s" % cond for cond in self.skip]
         conditional = ''
         if conditions:
@@ -329,6 +312,27 @@ class ServerCallback(MessageCallback):
     Stream(s) attached to the callback.
     """
 
+    @classmethod
+    def resolve_attr_spec(cls, spec, cb_obj, model):
+        """
+        Resolves a Callback attribute specification looking the
+        corresponding attribute up on the cb_obj, which should be a
+        bokeh model.
+        """
+        if not cb_obj:
+            raise Exception('Bokeh plot attribute %s could not be found' % spec)
+        spec = spec.split('.')
+        resolved = cb_obj
+        for p in spec[1:]:
+            if p == 'attributes':
+                continue
+            if isinstance(resolved, dict):
+                resolved = resolved.get(p)
+            else:
+                resolved = getattr(resolved, p, None)
+        return {'id': model.ref['id'], 'value': resolved}
+
+
     def on_change(self, attr, old, new):
         """
         Process change events adding timeout to process multiple concerted
@@ -365,7 +369,7 @@ def process_on_event(self):
             msg = {}
             for attr, path in self.attributes.items():
                 model_obj = self.plot_handles.get(self.models[0])
-                msg[attr] = resolve_attr_spec(path, event, model_obj)
+                msg[attr] = self.resolve_attr_spec(path, event, model_obj)
             self.on_msg(msg)
         self.plot.document.add_timeout_callback(self.process_on_event, 50)
 
@@ -381,7 +385,7 @@ def process_on_change(self):
             if attr_path[0] == 'cb_obj':
                 path = '.'.join(self.models[:1]+attr_path[1:])
             cb_obj = self.plot_handles.get(self.models[0])
-            msg[attr] = resolve_attr_spec(path, cb_obj, cb_obj)
+            msg[attr] = self.resolve_attr_spec(path, cb_obj, cb_obj)
 
         self.on_msg(msg)
         self.plot.document.add_timeout_callback(self.process_on_change, 50)

From 6ab88612f789183c9e1e908531df24461c330562 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 20:38:04 +0100
Subject: [PATCH 19/30] Minor cleanup on bokeh Callbacks

---
 holoviews/plotting/bokeh/callbacks.py | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index aa0ca02ddb..2f1555584e 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -36,7 +36,7 @@ class MessageCallback(object):
     on_events = []
 
     # List of change events on the models to listen to
-    on_change = []
+    on_changes = []
 
     _callbacks = {}
 
@@ -224,7 +224,7 @@ class CustomJSCallback(MessageCallback):
     _comm_type = JupyterCommJS
 
     @classmethod
-    def attributes_js(cls, attributes, handles):
+    def attributes_js(cls, attributes):
         """
         Generates JS code to look up attributes on JS objects from
         an attributes specification dictionary. If the specification
@@ -249,17 +249,17 @@ def attributes_js(cls, attributes, handles):
         conditional_template = 'if (({obj_name} != undefined)) {{ {assign} }}'
         code = ''
         for key, attr_path in attributes.items():
-            data_assign = "data['{key}'] = ".format(key=key)
+            data_assign = 'data["{key}"] = '.format(key=key)
             attrs = attr_path.split('.')
             obj_name = attrs[0]
-            attr_getters = ''.join(["['{attr}']".format(attr=attr)
+            attr_getters = ''.join(['["{attr}"]'.format(attr=attr)
                                     for attr in attrs[1:]])
             if obj_name not in ['cb_obj', 'cb_data']:
                 assign_str = assign_template.format(
                     assign=data_assign, obj_name=obj_name, attr_getters=attr_getters
                 )
                 code += conditional_template.format(
-                    obj_name=obj_name, id=handles[obj_name].ref['id'], assign=assign_str
+                    obj_name=obj_name, assign=assign_str
                 )
             else:
                 assign_str = ''.join([data_assign, obj_name, attr_getters, ';\n'])
@@ -277,7 +277,7 @@ def get_customjs(self, references):
                                                 timeout=self.timeout,
                                                 debounce=self.debounce)
 
-        attributes = self.attributes_js(self.attributes, references)
+        attributes = self.attributes_js(self.attributes)
         conditions = ["%s" % cond for cond in self.skip]
         conditional = ''
         if conditions:
@@ -313,14 +313,17 @@ class ServerCallback(MessageCallback):
     """
 
     @classmethod
-    def resolve_attr_spec(cls, spec, cb_obj, model):
+    def resolve_attr_spec(cls, spec, cb_obj, model=None):
         """
         Resolves a Callback attribute specification looking the
         corresponding attribute up on the cb_obj, which should be a
-        bokeh model.
+        bokeh model. If not model is supplied cb_obj is assumed to
+        be the same as the model.
         """
         if not cb_obj:
             raise Exception('Bokeh plot attribute %s could not be found' % spec)
+        if model is None:
+            model = cb_obj
         spec = spec.split('.')
         resolved = cb_obj
         for p in spec[1:]:
@@ -385,7 +388,7 @@ def process_on_change(self):
             if attr_path[0] == 'cb_obj':
                 path = '.'.join(self.models[:1]+attr_path[1:])
             cb_obj = self.plot_handles.get(self.models[0])
-            msg[attr] = self.resolve_attr_spec(path, cb_obj, cb_obj)
+            msg[attr] = self.resolve_attr_spec(path, cb_obj)
 
         self.on_msg(msg)
         self.plot.document.add_timeout_callback(self.process_on_change, 50)
@@ -531,7 +534,7 @@ class PositionYCallback(PositionXYCallback):
     Returns the mouse x/y-position on mousemove event.
     """
 
-    attributes = {'y': 'cb_data.y'}
+    attributes = {'y': 'cb_obj.y'}
 
 
 class TapCallback(PositionXYCallback):

From 82074b8efb8710f57a987a3ee234bddf28e23c2f Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 21:01:10 +0100
Subject: [PATCH 20/30] Added tests for bokeh Callbacks

---
 tests/testbokehcallbacks.py | 79 +++++++++++++++++++++++++++++++++++++
 1 file changed, 79 insertions(+)
 create mode 100644 tests/testbokehcallbacks.py

diff --git a/tests/testbokehcallbacks.py b/tests/testbokehcallbacks.py
new file mode 100644
index 0000000000..96dbaaf3f4
--- /dev/null
+++ b/tests/testbokehcallbacks.py
@@ -0,0 +1,79 @@
+from unittest import SkipTest
+
+from holoviews.element.comparison import ComparisonTestCase
+
+try:
+    from holoviews.plotting.bokeh.callbacks import Callback
+    from holoviews.plotting.bokeh.util import bokeh_version
+
+    from bokeh.events import Tap
+    from bokeh.models import Range1d, Plot, ColumnDataSource
+    bokeh_renderer = Store.renderers['bokeh']
+except:
+    bokeh_renderer = None
+
+
+class TestBokehCustomJSCallbacks(ComparisonTestCase):
+
+    def setUp(self):
+        if bokeh_version < str('0.12.5'):
+            raise SkipTest("Bokeh >= 0.12.5 required to test callbacks")
+
+
+    def test_customjs_callback_attributes_js_for_model(self):
+        js_code = Callback.attributes_js({'x0': 'x_range.attributes.start',
+                                          'x1': 'x_range.attributes.end'})
+
+        code = (
+            'if ((x_range != undefined)) { data["x0"] = {id: x_range["id"], value: '
+            'x_range["attributes"]["start"]};\n }'
+            'if ((x_range != undefined)) { data["x1"] = {id: x_range["id"], value: '
+            'x_range["attributes"]["end"]};\n }'
+        )
+        self.assertEqual(js_code, code)
+
+    def test_customjs_callback_attributes_js_for_cb_obj(self):
+        js_code = Callback.attributes_js({'x': 'cb_obj.x',
+                                          'y': 'cb_obj.y'})
+        code = 'data["y"] = cb_obj["y"];\ndata["x"] = cb_obj["x"];\n'
+        self.assertEqual(js_code, code)
+
+    def test_customjs_callback_attributes_js_for_cb_data(self):
+        js_code = Callback.attributes_js({'x0': 'cb_data.geometry.x0',
+                                          'x1': 'cb_data.geometry.x1',
+                                          'y0': 'cb_data.geometry.y0',
+                                          'y1': 'cb_data.geometry.y1'})
+        code = ('data["y1"] = cb_data["geometry"]["y1"];\n'
+                'data["y0"] = cb_data["geometry"]["y0"];\n'
+                'data["x0"] = cb_data["geometry"]["x0"];\n'
+                'data["x1"] = cb_data["geometry"]["x1"];\n')
+        self.assertEqual(js_code, code)
+
+
+class TestBokehServerJSCallbacks(ComparisonTestCase):
+
+    def setUp(self):
+        if bokeh_version < str('0.12.5'):
+            raise SkipTest("Bokeh >= 0.12.5 required to test callbacks")
+
+    def test_server_callback_resolve_attr_spec_range1d_start(self):
+        range1d = Range1d(start=0, end=10)
+        msg = Callback.resolve_attr_spec('x_range.attributes.start', range1d)
+        self.assertEqual(msg, {'id': range1d.ref['id'], 'value': 0})
+
+    def test_server_callback_resolve_attr_spec_range1d_end(self):
+        range1d = Range1d(start=0, end=10)
+        msg = Callback.resolve_attr_spec('x_range.attributes.end', range1d)
+        self.assertEqual(msg, {'id': range1d.ref['id'], 'value': 10})
+
+    def test_server_callback_resolve_attr_spec_source_selected(self):
+        source = ColumnDataSource()
+        source.selected['1d']['indices'] = [1, 2, 3]
+        msg = Callback.resolve_attr_spec('cb_obj.selected.1d.indices', source)
+        self.assertEqual(msg, {'id': source.ref['id'], 'value': [1, 2, 3]})
+
+    def test_server_callback_resolve_attr_spec_tap_event(self):
+        plot = Plot()
+        event = Tap(plot, x=42)
+        msg = Callback.resolve_attr_spec('cb_obj.x', event, plot)
+        self.assertEqual(msg, {'id': plot.ref['id'], 'value': 42})

From a8a10a5928b7c1c66d3dcdda291a7e10ca4de5c4 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 22:30:00 +0100
Subject: [PATCH 21/30] Small fix for bokeh ServerCallback on_change events

---
 holoviews/plotting/bokeh/callbacks.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index 2f1555584e..cc7cc33df2 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -386,8 +386,11 @@ def process_on_change(self):
         for attr, path in self.attributes.items():
             attr_path = path.split('.')
             if attr_path[0] == 'cb_obj':
+                obj_handle = self.models[0]
                 path = '.'.join(self.models[:1]+attr_path[1:])
-            cb_obj = self.plot_handles.get(self.models[0])
+            else:
+                obj_handle = attr_path[0]
+            cb_obj = self.plot_handles.get(obj_handle)
             msg[attr] = self.resolve_attr_spec(path, cb_obj)
 
         self.on_msg(msg)

From 3342b0aba1c1fca5ddc48a41bfdf74250407914f Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 22:30:39 +0100
Subject: [PATCH 22/30] Allow supplying Document to BokehRenderer

---
 holoviews/plotting/bokeh/renderer.py | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/holoviews/plotting/bokeh/renderer.py b/holoviews/plotting/bokeh/renderer.py
index 6821028c1e..f00ff7a0ea 100644
--- a/holoviews/plotting/bokeh/renderer.py
+++ b/holoviews/plotting/bokeh/renderer.py
@@ -60,7 +60,7 @@ class BokehRenderer(Renderer):
 
     _loaded = False
 
-    def __call__(self, obj, fmt=None):
+    def __call__(self, obj, fmt=None, doc=None):
         """
         Render the supplied HoloViews component using the appropriate
         backend. The output is not a file format but a suitable,
@@ -70,22 +70,23 @@ def __call__(self, obj, fmt=None):
         info = {'file-ext': fmt, 'mime_type': MIME_TYPES[fmt]}
 
         if self.mode == 'server':
-            return self.server_doc(plot), info
+            return self.server_doc(plot, doc), info
         elif isinstance(plot, tuple(self.widgets.values())):
             return plot(), info
         elif fmt == 'html':
-            html = self.figure_data(plot)
+            html = self.figure_data(plot, doc=doc)
             html = "<div style='display: table; margin: 0 auto;'>%s</div>" % html
             return self._apply_post_render_hooks(html, obj, fmt), info
         elif fmt == 'json':
             return self.diff(plot), info
 
 
-    def server_doc(self, plot):
+    def server_doc(self, plot, doc=None):
         """
         Get server document.
         """
-        doc = curdoc()
+        if doc is None:
+            doc = curdoc()
         if isinstance(plot, BokehServerWidgets):
             plot.plot.document = doc
         else:
@@ -94,9 +95,9 @@ def server_doc(self, plot):
         return doc
 
 
-    def figure_data(self, plot, fmt='html', **kwargs):
+    def figure_data(self, plot, fmt='html', doc=None, **kwargs):
         model = plot.state
-        doc = Document()
+        doc = Document() if doc is None else doc
         for m in model.references():
             m._document = None
         doc.add_root(model)

From c65dcbb938ccf090106efda749562ec9a45bbefc Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 23:18:39 +0100
Subject: [PATCH 23/30] Simplified bokeh Callback initialization

---
 holoviews/plotting/bokeh/callbacks.py | 91 ++++++++++++++-------------
 1 file changed, 46 insertions(+), 45 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index cc7cc33df2..6d0bbfe47d 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -92,15 +92,31 @@ def on_msg(self, msg):
             stream._metadata = {}
 
 
-    def _get_plot_handles(self, plots):
+    def _init_plot_handles(self):
         """
-        Iterate over plots and find all unique plotting handles.
+        Find all requested plotting handles and cache them along
+        with the IDs of the models callbacks will be attached to.
         """
+        plots = [self.plot]
+        if self.plot.subplots:
+            plots += list(self.plot.subplots.values())
+
         handles = {}
         for plot in plots:
             for k, v in plot.handles.items():
                 handles[k] = v
-        return handles
+        self.plot_handles = handles
+
+        requested = {}
+        for h in self.models+self.extra_models:
+            if h in self.plot_handles:
+                requested[h] = handles[h]
+            elif h in self.extra_models:
+                print("Warning %s could not find the %s model. "
+                      "The corresponding stream may not work.")
+        self.handle_ids.update(self._get_stream_handle_ids(requested))
+
+        return requested
 
 
     def _get_stream_handle_ids(self, handles):
@@ -468,49 +484,34 @@ class Callback(CustomJSCallback, ServerCallback):
     """
 
     def initialize(self):
-        plots = [self.plot]
-        if self.plot.subplots:
-            plots += list(self.plot.subplots.values())
-
-        self.plot_handles = self._get_plot_handles(plots)
-        requested = {}
-        for h in self.models+self.extra_models:
-            if h in self.plot_handles:
-                requested[h] = self.plot_handles[h]
-            elif h in self.extra_models:
-                print("Warning %s could not find the %s model. "
-                      "The corresponding stream may not work.")
-        self.handle_ids.update(self._get_stream_handle_ids(requested))
+        handles = self._init_plot_handles()
+        for handle_name in self.models:
+            if handle_name not in handles:
+                warn_args = (handle_name, type(self.plot).__name__,
+                             type(self).__name__)
+                print('%s handle not found on %s, cannot '
+                      'attach %s callback' % warn_args)
+                continue
+            handle = handles[handle_name]
+
+            # Hash the plot handle with Callback type allowing multiple
+            # callbacks on one handle to be merged
+            cb_hash = (id(handle), id(type(self)))
+            if cb_hash in self._callbacks:
+                # Merge callbacks if another callback has already been attached
+                cb = self._callbacks[cb_hash]
+                cb.streams += self.streams
+                for k, v in self.handle_ids.items():
+                    cb.handle_ids[k].update(v)
+                continue
 
-        found = []
-        for plot in plots:
-            for handle_name in self.models:
-                if handle_name not in self.plot_handles:
-                    warn_args = (handle_name, type(self.plot).__name__,
-                                 type(self).__name__)
-                    print('%s handle not found on %s, cannot '
-                          'attach %s callback' % warn_args)
-                    continue
-                handle = self.plot_handles[handle_name]
-
-                # Hash the plot handle with Callback type allowing multiple
-                # callbacks on one handle to be merged
-                cb_hash = (id(handle), id(type(self)))
-                if cb_hash in self._callbacks:
-                    # Merge callbacks if another callback has already been attached
-                    cb = self._callbacks[cb_hash]
-                    cb.streams += self.streams
-                    for k, v in self.handle_ids.items():
-                        cb.handle_ids[k].update(v)
-                    continue
-
-                if self.plot.renderer.mode == 'server':
-                    self.set_server_callback(handle)
-                else:
-                    js_callback = self.get_customjs(requested)
-                    self.set_customjs_callback(js_callback, handle)
-                    self.callbacks.append(js_callback)
-                self._callbacks[cb_hash] = self
+            if self.plot.renderer.mode == 'server':
+                self.set_server_callback(handle)
+            else:
+                js_callback = self.get_customjs(requested)
+                self.set_customjs_callback(js_callback, handle)
+                self.callbacks.append(js_callback)
+            self._callbacks[cb_hash] = self
 
 
 

From a2fcb0cd5a7434f22902da2097e2378cb1fe28bd Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Thu, 6 Apr 2017 23:36:39 +0100
Subject: [PATCH 24/30] Moved bokeh server widget handling onto BokehRenderer

---
 holoviews/plotting/bokeh/renderer.py | 9 +++++++++
 holoviews/plotting/renderer.py       | 4 +---
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/holoviews/plotting/bokeh/renderer.py b/holoviews/plotting/bokeh/renderer.py
index f00ff7a0ea..5c84847a80 100644
--- a/holoviews/plotting/bokeh/renderer.py
+++ b/holoviews/plotting/bokeh/renderer.py
@@ -80,6 +80,15 @@ def __call__(self, obj, fmt=None, doc=None):
         elif fmt == 'json':
             return self.diff(plot), info
 
+    @bothmethod
+    def get_widget(self_or_cls, plot, widget_type, **kwargs):
+        if not isinstance(plot, Plot):
+            plot = self_or_cls.get_plot(plot)
+        if self_or_cls.mode == 'server':
+            return BokehServerWidgets(plot, renderer=self_or_cls.instance(), **kwargs)
+        else:
+            return super(BokehRenderer, self).get_widget(plot, widget_type, **kwargs)
+
 
     def server_doc(self, plot, doc=None):
         """
diff --git a/holoviews/plotting/renderer.py b/holoviews/plotting/renderer.py
index 00d2daead0..13cec36302 100644
--- a/holoviews/plotting/renderer.py
+++ b/holoviews/plotting/renderer.py
@@ -299,9 +299,7 @@ def get_widget(self_or_cls, plot, widget_type, **kwargs):
         if not isinstance(plot, Plot):
             plot = self_or_cls.get_plot(plot)
         dynamic = plot.dynamic
-        if widget_type == 'server':
-            pass
-        elif widget_type == 'auto':
+        if widget_type == 'auto':
             isuniform = plot.uniform
             if not isuniform:
                 widget_type = 'scrubber'

From b0e1f52d1ce62b46751c900bb262ef45cc8e7259 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 7 Apr 2017 00:00:06 +0100
Subject: [PATCH 25/30] Factored out class method to create bokeh widgets

---
 holoviews/plotting/bokeh/widgets.py | 107 +++++++++++++++++-----------
 1 file changed, 64 insertions(+), 43 deletions(-)

diff --git a/holoviews/plotting/bokeh/widgets.py b/holoviews/plotting/bokeh/widgets.py
index e50a112d01..939cd00f06 100644
--- a/holoviews/plotting/bokeh/widgets.py
+++ b/holoviews/plotting/bokeh/widgets.py
@@ -4,6 +4,7 @@
 from functools import partial
 
 import param
+import numpy as np
 from bokeh.io import _CommsHandle
 from bokeh.util.notebook import get_comms
 from bokeh.models.widgets import Select, Slider, AutocompleteInput, TextInput
@@ -64,55 +65,75 @@ def __init__(self, plot, renderer=None, **params):
         self._event_queue = []
 
 
-    def get_widgets(self):
-        # Generate widget data
-        widgets = OrderedDict()
-        lookups = {}
-        for idx, dim in enumerate(self.mock_obj.kdims):
-            label, lookup = None, None
-            if self.plot.dynamic:
-                if dim.values:
-                    if all(isnumeric(v) for v in dim.values):
-                        values = dim.values
-                        labels = [unicode(dim.pprint_value(v)) for v in dim.values]
-                        label = AutocompleteInput(value=labels[0], completions=labels,
-                                                  title=dim.pprint_label)
-                        widget = Slider(value=0, end=len(dim.values)-1, title=None, step=1)
-                        lookup = zip(values, labels)
-                    else:
-                        values = [(v, dim.pprint_value(v)) for v in dim.values]
-                        widget = Select(title=dim.pprint_label, value=values[0][0],
-                                        options=values)
-                else:
-                    start = dim.soft_range[0] if dim.soft_range[0] else dim.range[0]
-                    end = dim.soft_range[1] if dim.soft_range[1] else dim.range[1]
-                    int_type = isinstance(dim.type, type) and issubclass(dim.type, int)
-                    if isinstance(dim_range, int) or int_type:
-                        step = 1
-                    else:
-                        step = 10**(round(math.log10(dim_range))-3)
-                    label = TextInput(value=str(start), title=dim.pprint_label)
-                    widget = Slider(value=start, start=start,
-                                    end=end, step=step, title=None)
-            else:
-                values = (dim.values if dim.values else
-                            list(unique_array(self.mock_obj.dimension_values(dim.name))))
-                labels = [str(dim.pprint_value(v)) for v in values]
-                if isinstance(values[0], np.datetime64) or isnumeric(values[0]):
+    @classmethod
+    def create_widget(self, dim, holomap=None):
+        """"
+        Given a Dimension creates bokeh widgets to select along that
+        dimension. For numeric data a slider widget is created which
+        may be either discrete, if a holomap is supplied or the
+        Dimension.values are set, or a continuous widget for
+        DynamicMaps. If the slider is discrete the returned mapping
+        defines a mapping between values and labels making it possible
+        sync the two slider and label widgets. For non-numeric data
+        a simple dropdown selection widget is generated.
+        """
+        label, mapping = None, None
+        if holomap is None:
+            if dim.values:
+                if all(isnumeric(v) for v in dim.values):
+                    values = dim.values
+                    labels = [unicode(dim.pprint_value(v)) for v in dim.values]
                     label = AutocompleteInput(value=labels[0], completions=labels,
                                               title=dim.pprint_label)
-                    widget = Slider(value=0, end=len(dim.values)-1, title=None)
+                    widget = Slider(value=0, end=len(dim.values)-1, title=None, step=1)
+                    mapping = zip(values, labels)
                 else:
-                    widget = Select(title=dim.pprint_label, value=values[0],
-                                    options=list(zip(values, labels)))
-                lookup = zip(values, labels)
-            if label:
+                    values = [(v, dim.pprint_value(v)) for v in dim.values]
+                    widget = Select(title=dim.pprint_label, value=values[0][0],
+                                    options=values)
+            else:
+                start = dim.soft_range[0] if dim.soft_range[0] else dim.range[0]
+                end = dim.soft_range[1] if dim.soft_range[1] else dim.range[1]
+                int_type = isinstance(dim.type, type) and issubclass(dim.type, int)
+                if isinstance(dim_range, int) or int_type:
+                    step = 1
+                else:
+                    step = 10**(round(math.log10(dim_range))-3)
+                label = TextInput(value=str(start), title=dim.pprint_label)
+                widget = Slider(value=start, start=start,
+                                end=end, step=step, title=None)
+        else:
+            values = (dim.values if dim.values else
+                      list(unique_array(holomap.dimension_values(dim.name))))
+            labels = [str(dim.pprint_value(v)) for v in values]
+            if isinstance(values[0], np.datetime64) or isnumeric(values[0]):
+                label = AutocompleteInput(value=labels[0], completions=labels,
+                                          title=dim.pprint_label)
+                widget = Slider(value=0, end=len(dim.values)-1, title=None)
+            else:
+                widget = Select(title=dim.pprint_label, value=values[0],
+                                options=list(zip(values, labels)))
+            mapping = zip(values, labels)
+        return widget, label, mapping
+
+
+    def get_widgets(self):
+        """
+        Creates a set of widgets representing the dimensions on the
+        plot object used to instantiate the widgets class.
+        """
+        widgets = OrderedDict()
+        mappings = {}
+        for dim in self.mock_obj.kdims:
+            holomap = None if self.plot.dynamic else self.mock_obj
+            widget, label, mapping = self.create_widget(dim, holomap)
+            if label is not None:
                 label.on_change('value', partial(self.on_change, dim.pprint_label, 'label'))
             widget.on_change('value', partial(self.on_change, dim.pprint_label, 'widget'))
             widgets[dim.pprint_label] = (label, widget)
-            if lookup:
-                lookups[dim.pprint_label] = OrderedDict(lookup)
-        return widgets, lookups
+            if mapping:
+                mappings[dim.pprint_label] = OrderedDict(mapping)
+        return widgets, mappings
 
 
     def init_layout(self):

From d9fe1b756ce7d9cd20ba5f3add65b642aa8c809b Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 7 Apr 2017 00:53:21 +0100
Subject: [PATCH 26/30] Small fixes and improvements for bokeh widgets

---
 holoviews/plotting/bokeh/widgets.py | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/holoviews/plotting/bokeh/widgets.py b/holoviews/plotting/bokeh/widgets.py
index 939cd00f06..516318fecb 100644
--- a/holoviews/plotting/bokeh/widgets.py
+++ b/holoviews/plotting/bokeh/widgets.py
@@ -1,5 +1,6 @@
 from __future__ import unicode_literals
 
+import math
 import json
 from functools import partial
 
@@ -19,15 +20,19 @@
 
 class BokehServerWidgets(param.Parameterized):
     """
+    BokehServerWidgets create bokeh widgets corresponding to all the
+    key dimensions found on a BokehPlot instance. It currently supports
+    to types of widgets sliders (which may be discrete or continuous)
+    and dropdown widgets letting you select non-numeric values.
     """
 
-    basejs = param.String(default=None, doc="""
+    basejs = param.String(default=None, precedence=-1, doc="""
         Defines the local CSS file to be loaded for this widget.""")
 
-    extensionjs = param.String(default=None, doc="""
+    extensionjs = param.String(default=None, precedence=-1, doc="""
         Optional javascript extension file for a particular backend.""")
 
-    css = param.String(default=None, doc="""
+    css = param.String(default=None, precedence=-1, doc="""
         Defines the local CSS file to be loaded for this widget.""")
 
     position = param.ObjectSelector(default='right',
@@ -37,6 +42,9 @@ class BokehServerWidgets(param.Parameterized):
         objects=['fixed', 'stretch_both', 'scale_width',
                  'scale_height', 'scale_both'])
 
+    width = param.Integer(default=200, doc="""
+        Width of the widget box in pixels""")
+
     def __init__(self, plot, renderer=None, **params):
         super(BokehServerWidgets, self).__init__(**params)
         self.plot = plot
@@ -94,22 +102,23 @@ def create_widget(self, dim, holomap=None):
             else:
                 start = dim.soft_range[0] if dim.soft_range[0] else dim.range[0]
                 end = dim.soft_range[1] if dim.soft_range[1] else dim.range[1]
+                dim_range = end - start
                 int_type = isinstance(dim.type, type) and issubclass(dim.type, int)
                 if isinstance(dim_range, int) or int_type:
                     step = 1
                 else:
-                    step = 10**(round(math.log10(dim_range))-3)
+                    step = 10**((round(math.log10(dim_range))-3))
                 label = TextInput(value=str(start), title=dim.pprint_label)
                 widget = Slider(value=start, start=start,
                                 end=end, step=step, title=None)
         else:
             values = (dim.values if dim.values else
                       list(unique_array(holomap.dimension_values(dim.name))))
-            labels = [str(dim.pprint_value(v)) for v in values]
+            labels = [dim.pprint_value(v) for v in values]
             if isinstance(values[0], np.datetime64) or isnumeric(values[0]):
                 label = AutocompleteInput(value=labels[0], completions=labels,
                                           title=dim.pprint_label)
-                widget = Slider(value=0, end=len(dim.values)-1, title=None)
+                widget = Slider(value=0, end=len(values)-1, title=None, step=1)
             else:
                 widget = Select(title=dim.pprint_label, value=values[0],
                                 options=list(zip(values, labels)))
@@ -139,7 +148,7 @@ def get_widgets(self):
     def init_layout(self):
         widgets = [widget for d in self.widgets.values()
                    for widget in d if widget]
-        wbox = widgetbox(widgets, width=200)
+        wbox = widgetbox(widgets, width=self.width)
         if self.position in ['right', 'below']:
             plots = [self.plot.state, wbox]
         else:
@@ -231,8 +240,10 @@ def _plot_figure(self, idx, fig_format='json'):
                 msg = serialize_json(msg)
             return msg
 
+
 class BokehSelectionWidget(BokehWidget, SelectionWidget):
     pass
 
+
 class BokehScrubberWidget(BokehWidget, ScrubberWidget):
     pass

From f0c31c6d3ce9a3d653d9a6c1d7ce44b643fb03c6 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 7 Apr 2017 00:53:53 +0100
Subject: [PATCH 27/30] Added tests for BokehServerWidgets

---
 tests/testbokehwidgets.py | 112 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 112 insertions(+)
 create mode 100644 tests/testbokehwidgets.py

diff --git a/tests/testbokehwidgets.py b/tests/testbokehwidgets.py
new file mode 100644
index 0000000000..f15efafdb9
--- /dev/null
+++ b/tests/testbokehwidgets.py
@@ -0,0 +1,112 @@
+from unittest import SkipTest
+
+import numpy as np
+
+from holoviews.core import Dimension, NdMapping
+from holoviews.element.comparison import ComparisonTestCase
+
+try:
+    from holoviews.plotting.bokeh.callbacks import Callback
+    from holoviews.plotting.bokeh.widgets import BokehServerWidgets
+    from holoviews.plotting.bokeh.util import bokeh_version
+
+    from bokeh.models.widgets import Select, Slider, AutocompleteInput, TextInput
+except:
+    BokehServerWidgets = None
+
+
+class TestBokehServerWidgets(ComparisonTestCase):
+
+    def setUp(self):
+        if not BokehServerWidgets:
+            raise SkipTest("Bokeh required to test BokehServerWidgets")
+
+    def test_bokeh_server_dynamic_range_int(self):
+        dim = Dimension('x', range=(3, 11))
+        widget, label, mapping = BokehServerWidgets.create_widget(dim)
+        self.assertIsInstance(widget, Slider)
+        self.assertEqual(widget.value, 3)
+        self.assertEqual(widget.start, 3)
+        self.assertEqual(widget.end, 11)
+        self.assertEqual(widget.step, 1)
+        self.assertIsInstance(label, TextInput)
+        self.assertEqual(label.title, dim.pprint_label)
+        self.assertEqual(label.value, '3')
+        self.assertIs(mapping, None)
+
+    def test_bokeh_server_dynamic_range_float(self):
+        dim = Dimension('x', range=(3.1, 11.2))
+        widget, label, mapping = BokehServerWidgets.create_widget(dim)
+        self.assertIsInstance(widget, Slider)
+        self.assertEqual(widget.value, 3.1)
+        self.assertEqual(widget.start, 3.1)
+        self.assertEqual(widget.end, 11.2)
+        self.assertEqual(widget.step, 0.01)
+        self.assertIsInstance(label, TextInput)
+        self.assertEqual(label.title, dim.pprint_label)
+        self.assertEqual(label.value, '3.1')
+        self.assertIs(mapping, None)
+
+    def test_bokeh_server_dynamic_values_int(self):
+        values = list(range(3, 11))
+        dim = Dimension('x', values=values)
+        widget, label, mapping = BokehServerWidgets.create_widget(dim)
+        self.assertIsInstance(widget, Slider)
+        self.assertEqual(widget.value, 0)
+        self.assertEqual(widget.start, 0)
+        self.assertEqual(widget.end, 7)
+        self.assertEqual(widget.step, 1)
+        self.assertIsInstance(label, AutocompleteInput)
+        self.assertEqual(label.title, dim.pprint_label)
+        self.assertEqual(label.value, '3')
+        self.assertEqual(mapping, [(v, dim.pprint_value(v)) for v in values])
+
+    def test_bokeh_server_dynamic_values_float(self):
+        values = list(np.linspace(3.1, 11.2, 7))
+        dim = Dimension('x', values=values)
+        widget, label, mapping = BokehServerWidgets.create_widget(dim)
+        self.assertIsInstance(widget, Slider)
+        self.assertEqual(widget.value, 0)
+        self.assertEqual(widget.start, 0)
+        self.assertEqual(widget.end, 6)
+        self.assertEqual(widget.step, 1)
+        self.assertIsInstance(label, AutocompleteInput)
+        self.assertEqual(label.title, dim.pprint_label)
+        self.assertEqual(label.value, '3.1')
+        self.assertEqual(mapping, [(v, dim.pprint_value(v)) for v in values])
+
+    def test_bokeh_server_dynamic_values_str(self):
+        values = [chr(65+i) for i in range(10)]
+        dim = Dimension('x', values=values)
+        widget, label, mapping = BokehServerWidgets.create_widget(dim)
+        self.assertIsInstance(widget, Select)
+        self.assertEqual(widget.value, 'A')
+        self.assertEqual(widget.options, list(zip(values, values)))
+        self.assertEqual(widget.title, dim.pprint_label)
+        self.assertIs(mapping, None)
+        self.assertIs(label, None)
+
+    def test_bokeh_server_static_numeric_values(self):
+        dim = Dimension('x')
+        ndmap = NdMapping({i: None for i in range(3, 12)}, kdims=['x']) 
+        widget, label, mapping = BokehServerWidgets.create_widget(dim, ndmap)
+        self.assertIsInstance(widget, Slider)
+        self.assertEqual(widget.value, 0)
+        self.assertEqual(widget.start, 0)
+        self.assertEqual(widget.end, 8)
+        self.assertEqual(widget.step, 1)
+        self.assertIsInstance(label, AutocompleteInput)
+        self.assertEqual(label.title, dim.pprint_label)
+        self.assertEqual(label.value, '3')
+        self.assertEqual(mapping, [(k, dim.pprint_value(k)) for k in ndmap.keys()])
+
+    def test_bokeh_server_dynamic_values_str(self):
+        keys = [chr(65+i) for i in range(10)]
+        ndmap = NdMapping({i: None for i in keys}, kdims=['x'])
+        dim = Dimension('x') 
+        widget, label, mapping = BokehServerWidgets.create_widget(dim, ndmap)
+        self.assertIsInstance(widget, Select)
+        self.assertEqual(widget.value, 'A')
+        self.assertEqual(widget.options, list(zip(keys, keys)))
+        self.assertEqual(widget.title, dim.pprint_label)
+        self.assertEqual(mapping, [(k, dim.pprint_value(k)) for k in ndmap.keys()])

From 171e9caf0f8c7ab7eaaa149a3e5732eebc96c875 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 7 Apr 2017 00:57:21 +0100
Subject: [PATCH 28/30] Fixed unreferenced variable bugs

---
 holoviews/plotting/bokeh/callbacks.py | 2 +-
 holoviews/plotting/bokeh/renderer.py  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index 6d0bbfe47d..cfa5c70efb 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -508,7 +508,7 @@ def initialize(self):
             if self.plot.renderer.mode == 'server':
                 self.set_server_callback(handle)
             else:
-                js_callback = self.get_customjs(requested)
+                js_callback = self.get_customjs(handles)
                 self.set_customjs_callback(js_callback, handle)
                 self.callbacks.append(js_callback)
             self._callbacks[cb_hash] = self
diff --git a/holoviews/plotting/bokeh/renderer.py b/holoviews/plotting/bokeh/renderer.py
index 5c84847a80..63b1db2765 100644
--- a/holoviews/plotting/bokeh/renderer.py
+++ b/holoviews/plotting/bokeh/renderer.py
@@ -87,7 +87,7 @@ def get_widget(self_or_cls, plot, widget_type, **kwargs):
         if self_or_cls.mode == 'server':
             return BokehServerWidgets(plot, renderer=self_or_cls.instance(), **kwargs)
         else:
-            return super(BokehRenderer, self).get_widget(plot, widget_type, **kwargs)
+            return super(BokehRenderer, self_or_cls).get_widget(plot, widget_type, **kwargs)
 
 
     def server_doc(self, plot, doc=None):

From 4e8073a43f62b1c173151c7b78d004ab97eb8664 Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 7 Apr 2017 01:11:20 +0100
Subject: [PATCH 29/30] Various python3 fixes

---
 holoviews/plotting/bokeh/callbacks.py |  2 +-
 holoviews/plotting/bokeh/widgets.py   | 15 ++++++++-------
 tests/testbokehcallbacks.py           |  8 ++++----
 tests/testbokehwidgets.py             |  2 +-
 4 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index cfa5c70efb..7f6d0a1f8e 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -264,7 +264,7 @@ def attributes_js(cls, attributes):
         assign_template = '{assign}{{id: {obj_name}["id"], value: {obj_name}{attr_getters}}};\n'
         conditional_template = 'if (({obj_name} != undefined)) {{ {assign} }}'
         code = ''
-        for key, attr_path in attributes.items():
+        for key, attr_path in sorted(attributes.items()):
             data_assign = 'data["{key}"] = '.format(key=key)
             attrs = attr_path.split('.')
             obj_name = attrs[0]
diff --git a/holoviews/plotting/bokeh/widgets.py b/holoviews/plotting/bokeh/widgets.py
index 516318fecb..6de750fdae 100644
--- a/holoviews/plotting/bokeh/widgets.py
+++ b/holoviews/plotting/bokeh/widgets.py
@@ -12,7 +12,8 @@
 from bokeh.layouts import layout, gridplot, widgetbox, row, column
 
 from ...core import Store, NdMapping, OrderedDict
-from ...core.util import drop_streams, unique_array, isnumeric, wrap_tuple_streams
+from ...core.util import (drop_streams, unique_array, isnumeric,
+                          wrap_tuple_streams, unicode)
 from ..widgets import NdWidget, SelectionWidget, ScrubberWidget
 from .util import serialize_json
 
@@ -70,7 +71,7 @@ def __init__(self, plot, renderer=None, **params):
         if self.plot.renderer.mode == 'default':
             self.attach_callbacks()
         self.state = self.init_layout()
-        self._event_queue = []
+        self._queue = []
 
 
     @classmethod
@@ -94,7 +95,7 @@ def create_widget(self, dim, holomap=None):
                     label = AutocompleteInput(value=labels[0], completions=labels,
                                               title=dim.pprint_label)
                     widget = Slider(value=0, end=len(dim.values)-1, title=None, step=1)
-                    mapping = zip(values, labels)
+                    mapping = list(zip(values, labels))
                 else:
                     values = [(v, dim.pprint_value(v)) for v in dim.values]
                     widget = Select(title=dim.pprint_label, value=values[0][0],
@@ -119,10 +120,10 @@ def create_widget(self, dim, holomap=None):
                 label = AutocompleteInput(value=labels[0], completions=labels,
                                           title=dim.pprint_label)
                 widget = Slider(value=0, end=len(values)-1, title=None, step=1)
+                mapping = list(zip(values, labels))
             else:
                 widget = Select(title=dim.pprint_label, value=values[0],
                                 options=list(zip(values, labels)))
-            mapping = zip(values, labels)
         return widget, label, mapping
 
 
@@ -166,7 +167,7 @@ def attach_callbacks(self):
 
 
     def on_change(self, dim, widget_type, attr, old, new):
-        self._event_queue.append((dim, widget_type, attr, old, new))
+        self._queue.append((dim, widget_type, attr, old, new))
         if self.update not in self.plot.document._session_callbacks:
             self.plot.document.add_timeout_callback(self.update, 50)
 
@@ -175,9 +176,9 @@ def update(self):
         """
         Handle update events on bokeh server.
         """
-        if not self._event_queue:
+        if not self._queue:
             return
-        dim, widget_type, attr, old, new = self._event_queue[-1]
+        dim, widget_type, attr, old, new = self._queue[-1]
 
         label, widget = self.widgets[dim]
         if widget_type == 'label':
diff --git a/tests/testbokehcallbacks.py b/tests/testbokehcallbacks.py
index 96dbaaf3f4..6cc2f545cb 100644
--- a/tests/testbokehcallbacks.py
+++ b/tests/testbokehcallbacks.py
@@ -35,7 +35,7 @@ def test_customjs_callback_attributes_js_for_model(self):
     def test_customjs_callback_attributes_js_for_cb_obj(self):
         js_code = Callback.attributes_js({'x': 'cb_obj.x',
                                           'y': 'cb_obj.y'})
-        code = 'data["y"] = cb_obj["y"];\ndata["x"] = cb_obj["x"];\n'
+        code = 'data["x"] = cb_obj["x"];\ndata["y"] = cb_obj["y"];\n'
         self.assertEqual(js_code, code)
 
     def test_customjs_callback_attributes_js_for_cb_data(self):
@@ -43,10 +43,10 @@ def test_customjs_callback_attributes_js_for_cb_data(self):
                                           'x1': 'cb_data.geometry.x1',
                                           'y0': 'cb_data.geometry.y0',
                                           'y1': 'cb_data.geometry.y1'})
-        code = ('data["y1"] = cb_data["geometry"]["y1"];\n'
+        code = ('data["x0"] = cb_data["geometry"]["x0"];\n'
+                'data["x1"] = cb_data["geometry"]["x1"];\n'
                 'data["y0"] = cb_data["geometry"]["y0"];\n'
-                'data["x0"] = cb_data["geometry"]["x0"];\n'
-                'data["x1"] = cb_data["geometry"]["x1"];\n')
+                'data["y1"] = cb_data["geometry"]["y1"];\n')
         self.assertEqual(js_code, code)
 
 
diff --git a/tests/testbokehwidgets.py b/tests/testbokehwidgets.py
index f15efafdb9..b2caf509cd 100644
--- a/tests/testbokehwidgets.py
+++ b/tests/testbokehwidgets.py
@@ -109,4 +109,4 @@ def test_bokeh_server_dynamic_values_str(self):
         self.assertEqual(widget.value, 'A')
         self.assertEqual(widget.options, list(zip(keys, keys)))
         self.assertEqual(widget.title, dim.pprint_label)
-        self.assertEqual(mapping, [(k, dim.pprint_value(k)) for k in ndmap.keys()])
+        self.assertIs(mapping, None)

From 957b96bafb74df5086d6d2074f5944d669e8a32a Mon Sep 17 00:00:00 2001
From: Philipp Rudiger <P.Rudiger@ed.ac.uk>
Date: Fri, 7 Apr 2017 01:30:02 +0100
Subject: [PATCH 30/30] Improved docstrings for bokeh server features

---
 holoviews/plotting/bokeh/callbacks.py | 2 +-
 holoviews/plotting/bokeh/renderer.py  | 4 +++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/holoviews/plotting/bokeh/callbacks.py b/holoviews/plotting/bokeh/callbacks.py
index 7f6d0a1f8e..d73546557d 100644
--- a/holoviews/plotting/bokeh/callbacks.py
+++ b/holoviews/plotting/bokeh/callbacks.py
@@ -95,7 +95,7 @@ def on_msg(self, msg):
     def _init_plot_handles(self):
         """
         Find all requested plotting handles and cache them along
-        with the IDs of the models callbacks will be attached to.
+        with the IDs of the models the callbacks will be attached to.
         """
         plots = [self.plot]
         if self.plot.subplots:
diff --git a/holoviews/plotting/bokeh/renderer.py b/holoviews/plotting/bokeh/renderer.py
index 63b1db2765..7f0b97529b 100644
--- a/holoviews/plotting/bokeh/renderer.py
+++ b/holoviews/plotting/bokeh/renderer.py
@@ -37,7 +37,9 @@ class BokehRenderer(Renderer):
 
     mode = param.ObjectSelector(default='default',
                                 objects=['default', 'server'], doc="""
-         Whether to render the DynamicMap in regular or server mode. """)
+        Whether to render the object in regular or server mode. In server
+        mode a bokeh Document will be returned which can be served as a
+        bokeh server app. By default renders all output is rendered to HTML.""")
 
     # Defines the valid output formats for each mode.
     mode_formats = {'fig': {'default': ['html', 'json', 'auto'],