Docserver overhaul: Gitiles away from me.

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

+# Copyright 2015 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 posixpath
+
+from environment import GetAppVersion
+from future import Future
+from urllib import urlencode
+from urlparse import urlparse, parse_qs
+
+def _MakeHeaders(headers={}):
+  headers['User-Agent'] = 'Chomium docserver %s' % GetAppVersion()
+  headers['Cache-Control'] = 'max-age=0'
+  return headers
+
+
+def _AddQueryToUrl(url, new_query):
+  """Adds query paramters to a URL. This merges the given set of query params
+  with any that were already a part of the URL.
+  """
+  parsed_url = urlparse(url)
+  query = parse_qs(parsed_url.query)
+  query.update(new_query)
+  query_string = urlencode(query, True)
+  return '%s://%s%s?%s#%s' % (parsed_url.scheme, parsed_url.netloc,
+      parsed_url.path, query_string, parsed_url.fragment)
+
+
+class UrlFetcher(object):
+  def __init__(self):
+    self._base_path = None
+
+  def SetBasePath(self, base_path):
+    assert base_path is None or not base_path.endswith('/'), base_path
+    self._base_path = base_path
+
+  def Fetch(self, url, headers={}, query={}):
+    return self.FetchImpl(_AddQueryToUrl(self._FromBasePath(url), query),
+        _MakeHeaders(headers))
+
+  def FetchAsync(self, url, headers={}, query={}):
+    return self.FetchAsyncImpl(_AddQueryToUrl(self._FromBasePath(url), query),
+        _MakeHeaders(headers))
+
+  def FetchImpl(self, url, headers):
+    """Fetches a URL synchronously.
+    """
+    raise NotImplementedError(self.__class__)
+
+  def FetchAsyncImpl(self, url, headers):
+    """Fetches a URL asynchronously and returns a Future with the result.
+    """
+    raise NotImplementedError(self.__class__)
+
+  def _FromBasePath(self, url):
+    assert not url.startswith('/'), url
+    if self._base_path is not None:
+      url = posixpath.join(self._base_path, url) if url else self._base_path
+    return url