Add mockserver_textpb_to_binary.py script.

R=harringtond@chromium.org

Bug: 1044242
Change-Id: I5e7cd4285891420db66af423257ce7ee974e63a3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2013261
Commit-Queue: Arthur Wang <wuwang@chromium.org>
Reviewed-by: Dan H <harringtond@chromium.org>
Cr-Commit-Position: refs/heads/master@{#734274}

components/feed/tools/mockserver_textpb_to_binary.py

+#!/usr/bin/python3
+# Copyright 2020 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.
+
+# Lint as: python3
+"""The tool converts a textpb into a binary proto using chromium protoc binary.
+
+After converting a feed response textpb file into a mockserver textpb file using
+the proto_convertor script, then a engineer runs this script to encode the
+mockserver textpb file into a binary proto file that is being used by the feed
+card render test (Refers to go/create-a-feed-card-render-test for more).
+
+Make sure you have absl-py installed via pip install absl-py.
+
+Usage example:
+    python ./mockserver_textpb_to_binary.py
+    --chromium_path ~/chromium/src
+    --output_file /tmp/binary.pb
+    --source_file ~/tmp/original.textpb
+    --alsologtostderr
+"""
+
+import glob
+import os
+import subprocess
+
+from absl import app
+from absl import flags
+
+FLAGS = flags.FLAGS
+FLAGS = flags.FLAGS
+flags.DEFINE_string('chromium_path', '', 'The path of your chromium depot.')
+flags.DEFINE_string('output_file', '', 'The target output binary file path.')
+flags.DEFINE_string('source_file', '',
+                    'The source proto file, in textpb format, path.')
+
+CMD_TEMPLATE = r'cat {} | {} --encode={} -I{} -I$(find {} -name "*.proto") > {}'
+ENCODE_NAMESPACE = 'components.feed.core.proto.wire.mockserver.MockServer'
+COMPONENT_FEED_PROTO_PATH = 'components/feed/core/proto'
+_protoc_path = None
+
+
+def protoc_path(root_dir):
+  """Returns the path to the proto compiler, protoc."""
+  global _protoc_path
+  if not _protoc_path:
+    protoc_list = list(
+        glob.glob(os.path.join(root_dir, "out") + "/*/protoc")) + list(
+            glob.glob(os.path.join(root_dir, "out") + "/*/*/protoc"))
+    if not len(protoc_list):
+      print("Can't find a suitable build output directory",
+            "(it should have protoc)")
+      sys.exit(1)
+    _protoc_path = protoc_list[0]
+  return _protoc_path
+
+
+def main(argv):
+  if len(argv) > 1:
+    raise app.UsageError('Too many command-line arguments.')
+  if not FLAGS.chromium_path:
+    raise app.UsageError('chromium_path flag must be set.')
+  if not FLAGS.source_file:
+    raise app.UsageError('source_file flag must be set.')
+  if not FLAGS.output_file:
+    raise app.UsageError('output_file flag must be set.')
+
+  protoc_cmd = CMD_TEMPLATE.format(
+      FLAGS.source_file, protoc_path(FLAGS.chromium_path), ENCODE_NAMESPACE,
+      FLAGS.chromium_path,
+      os.path.join(FLAGS.chromium_path,
+                   COMPONENT_FEED_PROTO_PATH), FLAGS.output_file)
+  subprocess.call(protoc_cmd, shell=True)
+
+
+if __name__ == '__main__':
+  app.run(main)