Add a preliminary Python API for retrieving Google API keys.

google_apis/google_api_keys.py

Index: google_apis/google_api_keys.py
diff --git a/google_apis/google_api_keys.py b/google_apis/google_api_keys.py
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index 0000000000000000000000000000000000000000..26fd23632db2020426b2f2f92ccfd486e9db6cf1
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+++ b/google_apis/google_api_keys.py
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+#!/usr/bin/env python
+# 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.
+
+"""Python API for retrieving API keys.
+
+Note that this cannot have the exact same semantics (at the moment) as
+the C++ API in google_api_keys.h, since it does not have access to gyp
+variables or preprocessor defines.
+
+TODO(joi): Give this have the same semantics as the C++ API.
+"""
+
+import os
+import re
+import sys
+
+
+# The token returned when an API key is unset.
+DUMMY_TOKEN = 'dummytoken'
+
+
+def _GetTokenFromOfficialFile(token_name):
+  """Parses the token from the official file if it exists, else returns None."""
+  official_path = os.path.join(sys.path[0],
+                               'internal/google_chrome_api_keys.h')
+  if not os.path.isfile(official_path):
+    return None
+
+  line_regexp = '^#define\s*%s\s*"([^"]+)"' % token_name
+  line_pattern = re.compile(line_regexp)
+  def ParseLine(current_line):
+    result = line_pattern.match(current_line)
+    if result:
+      return result.group(1)
+    else:
+      return None
+
+  with open(official_path) as f:
+    current_line = ''
+    for line in f:
+      if line.endswith('\\\n'):
+        current_line += line[:-2]
+      else:
+        # Last line in multi-line #define, or a line that is not a
+        # continuation line.
+        current_line += line
+        token = ParseLine(current_line)
+        if token:
+          if current_line.count('"') != 2:
+            raise Exception(
+              'Embedded quotes and multi-line strings are not supported.')
+          return token
+        current_line = ''
+    return None
+
+
+def _GetToken(token_name):
+  """Returns the API token with the given name, or DUMMY_TOKEN by default."""
+  if token_name in os.environ:
+    return os.environ[token_name]
+  token = _GetTokenFromOfficialFile(token_name)
+  if token:
+    return token
+  else:
+    return DUMMY_TOKEN
+
+
+def GetAPIKey():
+  """Returns the simple API key."""
+  return _GetToken('GOOGLE_API_KEY')
+
+
+def GetClientID(client_name):
+  """Returns the OAuth 2.0 client ID for the client of the given name."""
+  return _GetToken('GOOGLE_CLIENT_ID_%s' % client_name)
+
+
+def GetClientSecret(client_name):
+  """Returns the OAuth 2.0 client secret for the client of the given name."""
+  return _GetToken('GOOGLE_CLIENT_SECRET_%s' % client_name)
+
+
+if __name__ == "__main__":
+  print 'GOOGLE_API_KEY=%s' % GetAPIKey()
+  print 'GOOGLE_CLIENT_ID_MAIN=%s' % GetClientID('MAIN')
+  print 'GOOGLE_CLIENT_SECRET_MAIN=%s' % GetClientSecret('MAIN')
+  print 'GOOGLE_CLIENT_ID_CLOUD_PRINT=%s' % GetClientID('CLOUD_PRINT')
+  print 'GOOGLE_CLIENT_SECRET_CLOUD_PRINT=%s' % GetClientSecret('CLOUD_PRINT')
+  print 'GOOGLE_CLIENT_ID_REMOTING=%s' % GetClientID('REMOTING')
+  print 'GOOGLE_CLIENT_SECRET_REMOTING=%s' % GetClientSecret('REMOTING')