Initial checkin of gRPC to third_party/

third_party/grpc/examples/python/route_guide/route_guide_server.py

+# Copyright 2015-2016, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""The Python implementation of the gRPC route guide server."""
+
+import time
+import math
+
+import route_guide_pb2
+import route_guide_resources
+
+_ONE_DAY_IN_SECONDS = 60 * 60 * 24
+
+
+def get_feature(feature_db, point):
+  """Returns Feature at given location or None."""
+  for feature in feature_db:
+    if feature.location == point:
+      return feature
+  return None
+
+
+def get_distance(start, end):
+  """Distance between two points."""
+  coord_factor = 10000000.0
+  lat_1 = start.latitude / coord_factor
+  lat_2 = end.latitude / coord_factor
+  lon_1 = start.latitude / coord_factor
+  lon_2 = end.longitude / coord_factor
+  lat_rad_1 = math.radians(lat_1)
+  lat_rad_2 = math.radians(lat_2)
+  delta_lat_rad = math.radians(lat_2 - lat_1)
+  delta_lon_rad = math.radians(lon_2 - lon_1)
+
+  a = (pow(math.sin(delta_lat_rad / 2), 2) +
+       (math.cos(lat_rad_1) * math.cos(lat_rad_2) *
+        pow(math.sin(delta_lon_rad / 2), 2)))
+  c = 2 * math.atan2(math.sqrt(a), math.sqrt(1 - a))
+  R = 6371000; # metres
+  return R * c;
+
+class RouteGuideServicer(route_guide_pb2.BetaRouteGuideServicer):
+  """Provides methods that implement functionality of route guide server."""
+
+  def __init__(self):
+    self.db = route_guide_resources.read_route_guide_database()
+
+  def GetFeature(self, request, context):
+    feature = get_feature(self.db, request)
+    if feature is None:
+      return route_guide_pb2.Feature(name="", location=request)
+    else:
+      return feature
+
+  def ListFeatures(self, request, context):
+    left = min(request.lo.longitude, request.hi.longitude)
+    right = max(request.lo.longitude, request.hi.longitude)
+    top = max(request.lo.latitude, request.hi.latitude)
+    bottom = min(request.lo.latitude, request.hi.latitude)
+    for feature in self.db:
+      if (feature.location.longitude >= left and
+          feature.location.longitude <= right and
+          feature.location.latitude >= bottom and
+          feature.location.latitude <= top):
+        yield feature
+
+  def RecordRoute(self, request_iterator, context):
+    point_count = 0
+    feature_count = 0
+    distance = 0.0
+    prev_point = None
+
+    start_time = time.time()
+    for point in request_iterator:
+      point_count += 1
+      if get_feature(self.db, point):
+        feature_count += 1
+      if prev_point:
+        distance += get_distance(prev_point, point)
+      prev_point = point
+
+    elapsed_time = time.time() - start_time
+    return route_guide_pb2.RouteSummary(point_count=point_count,
+                                        feature_count=feature_count,
+                                        distance=int(distance),
+                                        elapsed_time=int(elapsed_time))
+
+  def RouteChat(self, request_iterator, context):
+    prev_notes = []
+    for new_note in request_iterator:
+      for prev_note in prev_notes:
+        if prev_note.location == new_note.location:
+          yield prev_note
+      prev_notes.append(new_note)
+
+
+def serve():
+  server = route_guide_pb2.beta_create_RouteGuide_server(RouteGuideServicer())
+  server.add_insecure_port('[::]:50051')
+  server.start()
+  try:
+    while True:
+      time.sleep(_ONE_DAY_IN_SECONDS)
+  except KeyboardInterrupt:
+    server.stop(0)
+
+if __name__ == '__main__':
+  serve()