Merge pull request #97 from sinoroc/make-chameleon-optional

Make chameleon optional

.travis.yml

@@ -6,5 +6,5 @@ python:
   - "3.7"
   - pypy
 install:
-  - pip install -e '.[tests]'
+  - pip install -e '.[tests,chameleonextractor]'
 script: py.test tests

setup.py

@@ -7,7 +7,6 @@
 install_requires = [
     'setuptools',
     'polib',
-    'Chameleon',
 ]
 
 tests_require = [
@@ -65,7 +64,10 @@ def run_tests(self):
       zip_safe=True,
       install_requires=install_requires,
       tests_require=tests_require,
-      extras_require={'tests': tests_require},
+      extras_require={
+          'tests': tests_require,
+          'chameleonextractor': ['Chameleon'],
+      },
       cmdclass={'test': PyTest},
       entry_points='''
       [console_scripts]
@@ -74,9 +76,9 @@ def run_tests(self):
 
       [lingua.extractors]
       python = lingua.extractors.python:PythonExtractor
-      chameleon = lingua.extractors.xml:ChameleonExtractor
-      xml = lingua.extractors.xml:ChameleonExtractor
-      zope = lingua.extractors.xml:ZopeExtractor
+      chameleon = lingua.extractors.xml:ChameleonExtractor [chameleonextractor]
+      xml = lingua.extractors.xml:ChameleonExtractor [chameleonextractor]
+      zope = lingua.extractors.xml:ZopeExtractor [chameleonextractor]
       zcml = lingua.extractors.zcml:ZCMLExtractor
       '''
       )

src/lingua/extractors/__init__.py

@@ -1,4 +1,5 @@
 from __future__ import print_function
+from pkg_resources import DistributionNotFound
 from pkg_resources import working_set
 import abc
 import collections
@@ -149,10 +150,16 @@ def __call__(self, filename, options, fileobj=None, lineno=0):
 
 def register_extractors():
     for entry_point in working_set.iter_entry_points('lingua.extractors'):
-        extractor = entry_point.load(require=True)
-        if not issubclass(extractor, Extractor):
-            raise ValueError(
-                u'Registered extractor must derive from ``Extractor``')
-        EXTRACTORS[entry_point.name] = extractor()
-        for extension in extractor.extensions:
-            EXTENSIONS[extension] = entry_point.name
+        try:
+            extractor = entry_point.load(require=True)
+        except DistributionNotFound:
+            # skip this entry point since at least one required dependency can
+            # not be found
+            extractor = None
+        if extractor:
+            if not issubclass(extractor, Extractor):
+                raise ValueError(
+                    u'Registered extractor must derive from ``Extractor``')
+            EXTRACTORS[entry_point.name] = extractor()
+            for extension in extractor.extensions:
+                EXTENSIONS[extension] = entry_point.name

src/lingua/extractors/babel.py

@@ -1,3 +1,4 @@
+from pkg_resources import DistributionNotFound
 from pkg_resources import working_set
 from .python import KEYWORDS
 from .python import parse_keyword
@@ -48,9 +49,15 @@ def __call__(self, filename, options, fileobj=None, firstline=0):
 def register_babel_plugins():
     for entry_point in working_set.iter_entry_points('babel.extractors'):
         name = entry_point.name
-        extractor = entry_point.load(require=True)
-        cls = type('BabelExtractor_%s' % name,
-                (BabelExtractor, object),
-                {'extractor': staticmethod(extractor),
-                 '__doc__': extractor.__doc__.splitlines()[0]})
-        EXTRACTORS['babel-%s' % name] = cls()
+        try:
+            extractor = entry_point.load(require=True)
+        except DistributionNotFound:
+            # skip this entry point since at least one required dependency can
+            # not be found
+            extractor = None
+        if extractor:
+            cls = type('BabelExtractor_%s' % name,
+                    (BabelExtractor, object),
+                    {'extractor': staticmethod(extractor),
+                     '__doc__': extractor.__doc__.splitlines()[0]})
+            EXTRACTORS['babel-%s' % name] = cls()