Merge pull request #662 from spumko/feature/ext

Plugin deps

lib/ext.js

@@ -0,0 +1,280 @@
+// Load modules
+
+var Domain = require('domain');
+var Boom = require('boom');
+var Async = require('async');
+var Utils = require('./utils');
+
+
+// Declare internals
+
+var internals = {};
+
+/*
+    Extension functions use the following signature: function (request, next) { next(); }
+*/
+
+module.exports = internals.Ext = function () {
+
+    this._events = {
+        onRequest: null,                            // New request, before handing over to the router (allows changes to the request method, url, etc.)
+        onPreHandler: null,                         // After validation and body parsing, before route handler
+        onPostHandler: null                         // After route handler returns, before sending response
+    };
+};
+
+
+internals.Ext.prototype.add = function (event, func, options) {
+
+    return this._add(event, func, options);
+};
+
+
+internals.Ext.prototype._add = function (event, func, options, plugin) {
+
+    options = options || {};
+
+    Utils.assert(['onRequest', 'onPreHandler', 'onPostHandler'].indexOf(event) !== -1, 'Unknown event type: ' + event);
+
+    this._events[event] = this._events[event] || []
+
+    var ext = {
+        priority: this._events[event].length,
+        before: [].concat(options.before || []),
+        after: [].concat(options.after || []),
+        group: plugin || '?',
+        func: func
+    };
+
+    // Validate rules
+
+    Utils.assert(ext.before.indexOf(ext.group) === -1, 'Plugin ext cannot come before itself (' + ext.plugin + ')');
+    Utils.assert(ext.before.indexOf('?') === -1, 'Plugin ext cannot come before unassociated exts');
+    Utils.assert(ext.after.indexOf(ext.group) === -1, 'Plugin ext cannot come after itself (' + ext.plugin + ')');
+    Utils.assert(ext.after.indexOf('?') === -1, 'Plugin ext cannot come after unassociated exts');
+
+    // Insert event
+
+    this._events[event].push(ext);
+    this.sort(event);
+};
+
+
+internals.Ext.prototype.invoke = function (request, event, callback) {
+
+    var handlers = this._events[event];            // onRequest, onPreHandler, onPostHandler
+    if (!handlers) {
+        return callback();
+    }
+
+    Async.forEachSeries(handlers, function (ext, next) {
+
+        internals.Ext.runProtected(request.log.bind(request), event, next, function (run, protectedNext) {
+
+            run(function () {
+
+                ext.func(request, protectedNext);
+            });
+        });
+    },
+    function (err) {
+
+        return callback(err);
+    });
+};
+
+
+internals.Ext.runProtected = function (log, tags, callback, setup) {
+
+    var domain = Domain.createDomain();
+
+    // Ensure only one callback returned
+
+    var isFinished = false;
+    var finish = function () {
+
+        if (isFinished) {
+            log(['duplicate', 'callback', 'error'].concat(tags || []));
+            return;
+        }
+
+        isFinished = true;
+
+        domain.exit();
+        return callback.apply(null, arguments);
+    };
+
+    setup(function (run) {
+
+        domain.on('error', function (err) {
+
+            domain.dispose();
+            log(['uncaught'].concat(tags || []), err);
+            return finish(Boom.internal('Uncaught error', err));
+        });
+
+        // Execute functon
+
+        domain.enter();
+        run();
+    },
+    finish);
+};
+
+
+internals.Ext.prototype.sort = function (event) {
+
+    var exts = this._events[event];
+    if (!exts) {
+        return;
+    }
+
+    // Sort
+
+    var graph = internals.getGraph(exts);
+    var ancestors = internals.getAncestors(graph);
+    var sorted = internals.topoSort(ancestors, exts.length);
+
+    var priorityIndex = {};
+    exts.forEach(function (ext) {
+
+        priorityIndex[ext.priority] = ext;
+    });
+
+    this._events[event] = sorted.map(function (value) {
+
+        return priorityIndex[value];
+    });
+};
+
+
+internals.getGraph = function (exts) {
+
+    var groups = {};
+    var graph = {};
+    var graphAfters = {};
+
+    for (var i = 0, il = exts.length; i < il; ++i) {
+        var ext = exts[i];
+        var priority = ext.priority;
+        var group = ext.group;
+
+        // Determine Groups
+
+        if (groups.hasOwnProperty(group)) {
+            if (groups[group].indexOf(priority) == -1) {
+                groups[group].push(priority);
+            }
+        }
+        else {
+            groups[group] = [priority];
+        }
+
+        // Build intermediary graph using 'before'
+
+        var before = ext.before;
+        graph[priority] = (graph[priority] || []).concat(before);
+
+        // Build second intermediary graph with 'after'
+
+        var after = ext.after;
+        for (var j = 0, jl = after.length; j < jl; ++j) {
+            graphAfters[after[j]] = (graphAfters[after[j]] || []).concat(priority);
+        }
+    }
+
+    // Expand intermediary graph
+
+    Object.keys(graph).forEach(function (node) {
+
+        var expandedGroups = [];
+        for (var groupIndex in graph[node]) {
+            var group = graph[node][groupIndex];
+            groups[group] = groups[group] || [];
+            groups[group].forEach(function (d) {
+                expandedGroups.push(d);
+            });
+        }
+        graph[node] = expandedGroups;
+    });
+
+    // Merge intermediary graph using graphAfters into final graph
+
+    var afterNodes = Object.keys(graphAfters);
+    for (var n in afterNodes) {
+        var group = afterNodes[n];
+
+        for (var itemIndex in groups[group]) {
+            var node = groups[group][itemIndex];
+            graph[node] = (graph[node] || []).concat(graphAfters[group])
+        }
+    }
+
+    return graph;
+};
+
+
+internals.getAncestors = function (graph) {
+
+    var ancestors = {};
+    var graphNodes = Object.keys(graph);
+    for (var i in graphNodes) {
+        var node = graphNodes[i];
+        var children = graph[node];
+
+        for (var j = 0, jl = children.length; j < jl; ++j) {
+            ancestors[children[j]] = (ancestors[children[j]] || []).concat(node);
+        }
+    }
+
+    return ancestors;
+};
+
+
+internals.topoSort = function (ancestorsGraph, length) {
+
+    var visited = {};
+    var sorted = [];
+    length = length || ancestorsGraph.length;
+
+    var ancNodes = Object.keys(ancestorsGraph);
+
+    for (var i = 0, il = length; i < il; ++i) {
+        var next = i;
+
+        if (ancestorsGraph[i]) {
+            next = null;
+            for (var j = 0, jl = length; j < jl; ++j) {
+                if (visited[j] == true) {
+                    continue;
+                }
+
+                if (!ancestorsGraph[j]) {
+                    ancestorsGraph[j] = [];
+                }
+
+                var shouldSeeCount = ancestorsGraph[j].length;
+                var seenCount = 0;
+                for (var l = 0, ll = shouldSeeCount; l < ll; ++l) {
+                    if (sorted.indexOf(ancestorsGraph[j][l]) >= 0) {
+                        ++seenCount;
+                    }
+                }
+
+                if (seenCount == shouldSeeCount) {
+                    next = j;
+                    break;
+                }
+            }
+        }
+
+        if (next !== null) {
+            next = next.toString();         // Normalize to string
+            visited[next] = true;
+            sorted.push(next);
+        }
+    }
+
+    Utils.assert(sorted.length === length, 'Invalid ext dependencies detected');
+    return sorted;
+};

lib/pack.js

@@ -112,6 +112,10 @@ internals.Pack.prototype.validate = function (plugin) {
         return new Error('Plugin missing name');
     }
 
+    if (plugin.name === 'hapi') {
+        return new Error('Plugin name cannot be \'hapi\'');
+    }
+
     if (!plugin.version) {
         return new Error('Plugin missing version');
     }
@@ -202,16 +206,16 @@ internals.Pack.prototype._register = function (plugin, permissions, options, cal
         }
 
         if (permissions.state) {
-            methods.state = function (name, options) {
+            methods.state = function () {
 
-                self._applySync(selection.servers, Server.prototype.state, [name, options]);
+                self._applySync(selection.servers, Server.prototype.state, arguments);
             };
         }
 
         if (permissions.helper) {
-            methods.helper = function (name, method, options) {
+            methods.helper = function () {
 
-                self._applySync(selection.servers, Server.prototype.helper, [name, method, options]);
+                self._applySync(selection.servers, Server.prototype.helper, arguments);
             };
         }
 
@@ -220,9 +224,9 @@ internals.Pack.prototype._register = function (plugin, permissions, options, cal
         }
 
         if (permissions.ext) {
-            methods.ext = function (event, func) {
+            methods.ext = function () {
 
-                self._applySync(selection.servers, Server.prototype.ext, [event, func]);
+                self._applySync(selection.servers, Server.prototype._ext, [arguments[0], arguments[1], arguments[2], plugin.name]);
             };
         }