rebaseline_server: allow users to generate SKP diff patches on a shared instance

gm/rebaseline_server/server.py

 #!/usr/bin/python
 
 """
 Copyright 2013 Google Inc.
 
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 
 HTTP server for our HTML rebaseline viewer.
 """
@@ skipping 30 matching lines @@
 # Server.results() property. See discussion at
 # https://codereview.chromium.org/195943004/diff/1/gm/rebaseline_server/server.py#newcode44
 # pylint: enable=C0301
 import compare_configs
 import compare_rendered_pictures
 import compare_to_expectations
 import download_actuals
 import imagediffdb
 import imagepairset
 import results as results_mod
+import writable_expectations as writable_expectations_mod
+
 
 PATHSPLIT_RE = re.compile('/([^/]+)/(.+)')
 
 # A simple dictionary of file name extensions to MIME types. The empty string
 # entry is used as the default when no extension was given or if the extension
 # has no entry in this dictionary.
 MIME_TYPE_MAP = {'': 'application/octet-stream',
                  'html': 'text/html',
                  'css': 'text/css',
                  'png': 'image/png',
                  'js': 'application/javascript',
                  'json': 'application/json'
                  }
 
 # Keys that server.py uses to create the toplevel content header.
 # NOTE: Keep these in sync with static/constants.js
 KEY__EDITS__MODIFICATIONS = 'modifications'
 KEY__EDITS__OLD_RESULTS_HASH = 'oldResultsHash'
 KEY__EDITS__OLD_RESULTS_TYPE = 'oldResultsType'
+KEY__LIVE_EDITS__MODIFICATIONS = 'modifications'
+KEY__LIVE_EDITS__SET_A_DESCRIPTIONS = 'setA'
+KEY__LIVE_EDITS__SET_B_DESCRIPTIONS = 'setB'
 
 DEFAULT_ACTUALS_DIR = results_mod.DEFAULT_ACTUALS_DIR
 DEFAULT_GM_SUMMARIES_BUCKET = download_actuals.GM_SUMMARIES_BUCKET
 DEFAULT_JSON_FILENAME = download_actuals.DEFAULT_JSON_FILENAME
 DEFAULT_PORT = 8888
 
 PARENT_DIRECTORY = os.path.dirname(os.path.realpath(__file__))
 TRUNK_DIRECTORY = os.path.dirname(os.path.dirname(PARENT_DIRECTORY))
 
 # Directory, relative to PARENT_DIRECTORY, within which the server will serve
@@ skipping 598 matching lines @@
   def do_POST(self):
     """ Handles all POST requests, forwarding them to the appropriate
         do_POST_* dispatcher. """
     # All requests must be of this form:
     #   /dispatcher
     # where 'dispatcher' indicates which do_POST_* dispatcher to run.
     logging.debug('do_POST: path="%s"' % self.path)
     normpath = posixpath.normpath(self.path)
     dispatchers = {
       '/edits': self.do_POST_edits,
+      '/live-edits': self.do_POST_live_edits,
     }
     try:
       dispatcher = dispatchers[normpath]
       dispatcher()
-      self.send_response(200)
     except:
       self.send_error(404)
       raise
 
   def do_POST_edits(self):
     """ Handle a POST request with modifications to GM expectations, in this
     format:
 
     {
       KEY__EDITS__OLD_RESULTS_TYPE: 'all',  # type of results that the client
@@ skipping 39 matching lines @@
         raise Exception('results of type "%s" changed while the client was '
                         'making modifications. The client should reload the '
                         'results and submit the modifications again.' %
                         oldResultsType)
       _SERVER.results.edit_expectations(data[KEY__EDITS__MODIFICATIONS])
 
     # Read the updated results back from disk.
     # We can do this in a separate thread; we should return our success message
     # to the UI as soon as possible.
     thread.start_new_thread(_SERVER.update_results, (True,))
+    self.send_response(200)
+
+  def do_POST_live_edits(self):
+    """ Handle a POST request with modifications to SKP expectations, in this
+    format:
+
+    {
+      KEY__LIVE_EDITS__SET_A_DESCRIPTIONS: {
+        # setA descriptions from the original data
+      },
+      KEY__LIVE_EDITS__SET_B_DESCRIPTIONS: {
+        # setB descriptions from the original data
+      },
+      KEY__LIVE_EDITS__MODIFICATIONS: [
+        # as needed by writable_expectations.modify()
+      ],
+    }
+
+    Raises an Exception if there were any problems.
+    """
+    content_type = self.headers[_HTTP_HEADER_CONTENT_TYPE]
+    if content_type != 'application/json;charset=UTF-8':
+      raise Exception('unsupported %s [%s]' % (
+          _HTTP_HEADER_CONTENT_TYPE, content_type))
+
+    content_length = int(self.headers[_HTTP_HEADER_CONTENT_LENGTH])
+    json_data = self.rfile.read(content_length)
+    data = json.loads(json_data)
+    logging.debug('do_POST_live_edits: received new GM expectations data [%s]' %
+                  data)
+    with writable_expectations_mod.WritableExpectations(
+        data[KEY__LIVE_EDITS__SET_A_DESCRIPTIONS]) as writable_expectations:
+      writable_expectations.modify(data[KEY__LIVE_EDITS__MODIFICATIONS])
+      diffs = writable_expectations.get_diffs()
+      # TODO(stephana): Move to a simpler web framework so we don't have to
+      # call these functions.  See http://skbug.com/2856 ('rebaseline_server:
+      # Refactor server to use a simple web framework')
+      self.send_response(200)
+      self.send_header('Content-type', 'text/plain')
+      self.end_headers()
+      self.wfile.write(diffs)
 
   def redirect_to(self, url):
     """ Redirect the HTTP client to a different url.
 
     Args:
       url: URL to redirect the HTTP client to
     """
     self.send_response(301)
     self.send_header('Location', url)
     self.end_headers()
@@ skipping 136 matching lines @@
                    reload_seconds=args.reload, config_pairs=config_pairs,
                    builder_regex_list=args.builders, boto_file_path=args.boto,
                    imagediffdb_threads=args.threads)
   if args.truncate:
     _SERVER.truncate_results = True
   _SERVER.run()
 
 
 if __name__ == '__main__':
   main()