Extensions Docs Server: Uniform handling of file not found errors

chrome/common/extensions/docs/server2/api_data_source.py

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import json
-import logging
 import os
 
+from file_system import FileNotFoundError
 from handlebar_dict_generator import HandlebarDictGenerator
 import third_party.json_schema_compiler.json_comment_eater as json_comment_eater
 import third_party.json_schema_compiler.model as model
 import third_party.json_schema_compiler.idl_schema as idl_schema
 import third_party.json_schema_compiler.idl_parser as idl_parser
 
 class APIDataSource(object):
   """This class fetches and loads JSON APIs from the FileSystem passed in with
   |cache_builder|, so the APIs can be plugged into templates.
   """
@@ skipping 34 matching lines @@
     self._idl_cache = idl_cache
     self._samples = samples
 
   def _GetFeature(self, path):
     # Remove 'experimental_' from path name to match the keys in
     # _permissions_features.json.
     path = path.replace('experimental_', '')
     try:
       perms = self._permissions_cache.GetFromFile(
           self._base_path + '/_permission_features.json')
-      api_perms = perms.get(path, None)
-      if api_perms['channel'] == 'dev':
-        api_perms['dev'] = True
-      return api_perms
-    except Exception:
+    except FileNotFoundError:
       return None
+    api_perms = perms.get(path, None)
+    if api_perms is None:
+      return None
+    if api_perms['channel'] == 'dev':
+      api_perms['dev'] = True
+    return api_perms
 
   def _GenerateHandlebarContext(self, api_name, handlebar, path):
     return_dict = { 'permissions': self._GetFeature(path) }
     return_dict.update(handlebar.Generate(
         self._FilterSamples(api_name, self._samples.values())))
     return return_dict
 
   def _FilterSamples(self, api_name, samples):
     api_search = '.' + api_name + '.'
     return [sample for sample in samples
             if any(api_search in api['name'] for api in sample['api_calls'])]
 
   def __getitem__(self, key):
     return self.get(key)
 
   def get(self, key):
     path, ext = os.path.splitext(key)
     unix_name = model.UnixName(path)
     json_path = unix_name + '.json'
     idl_path = unix_name + '.idl'
     try:
       return self._GenerateHandlebarContext(key,
           self._json_cache.GetFromFile(self._base_path + '/' + json_path),
           path)
-    except OSError:
-      try:
-        return self._GenerateHandlebarContext(key,
-            self._idl_cache.GetFromFile(self._base_path + '/' + idl_path),
-            path)
-      except OSError as e:
-        raise
+    except FileNotFoundError:
+      return self._GenerateHandlebarContext(key,
+          self._idl_cache.GetFromFile(self._base_path + '/' + idl_path),
+          path)

[not at google - send to devlin, 2012/08/10 06:12:16]

not sure, perhaps this should also be catching FileNotFoundError and return
None. It matches how the other data sources work.

(log error though)

[cduvall, 2012/08/10 17:25:16]

I would rather have it throw the exception than return None, so we actually know
when when it fails. Otherwise it will pass the integration test even if there is
no JSON/IDL schema.

[not at google - send to devlin, 2012/08/12 22:22:58]

Ok sg. Makes me wonder if there are other things (like, some of those other
handlers that return None rather than raising exceptions) that the integration
test won't pick up.

But yeah, no point logging if you're just raising it again anyway. So... back to
how it was?

[cduvall, 2012/08/13 18:44:05]

Done.