Add to_collection method returning an Xcollection

intake_esm/core.py

@@ -7,6 +7,7 @@
 import pandas as pd
 import pydantic
 import xarray as xr
+import xcollection as xc
 from fastprogress.fastprogress import progress_bar
 from intake.catalog import Catalog
 
@@ -441,9 +442,9 @@ def to_dataset_dict(
         aggregate: pydantic.StrictBool = None,
         skip_on_error: pydantic.StrictBool = False,
         **kwargs,
-    ) -> typing.Dict[str, xr.Dataset]:
+    ) -> typing.Collection[str, xc.Collection]:
         """
-        Load catalog entries into a dictionary of xarray datasets.
+        Load catalog entries into a Collection of xarray datasets.
 
         Parameters
         ----------
@@ -466,8 +467,8 @@ def to_dataset_dict(
 
         Returns
         -------
-        dsets : dict
-           A dictionary of xarray :py:class:`~xarray.Dataset`.
+        dsets : Collection
+           A Collection of xarray :py:class:`~xarray.Dataset`.
 
         Examples
         --------
@@ -506,7 +507,7 @@ def to_dataset_dict(
                 UserWarning,
                 stacklevel=2,
             )
-            return {}
+            return xc.Collection({})
 
         if (
             self.esmcat.aggregation_control.variable_column_name
@@ -548,7 +549,7 @@ def to_dataset_dict(
             self.progressbar = progressbar
         if self.progressbar:
             print(
-                f"""\n--> The keys in the returned dictionary of datasets are constructed as follows:\n\t'{self.key_template}'"""
+                f"""\n--> The keys in the returned Collection of datasets are constructed as follows:\n\t'{self.key_template}'"""
             )
         sources = {key: source(**source_kwargs) for key, source in self.items()}
         datasets = {}
@@ -570,6 +571,7 @@ def to_dataset_dict(
                     if not skip_on_error:
                         raise exc
         self.datasets = self._create_derived_variables(datasets, skip_on_error)
+        self.datasets = xc.Collection(self.datasets)
         return self.datasets
 
     def _create_derived_variables(self, datasets, skip_on_error):

requirements.txt

@@ -7,3 +7,4 @@ requests>=2.24.0
 xarray>=0.19
 zarr>=2.5
 pydantic>=1.8.2
+git+https://github.com/NCAR/xcollection.git

setup.py

@@ -7,7 +7,7 @@
 from setuptools import find_packages, setup
 
 with open('requirements.txt') as f:
-    install_requires = f.read().strip().split('\n')
+    install_requires = f.read().strip().split('\n')[0:-1]
 
 
 if exists('README.md'):