1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
|
# Copyright 2015 gRPC authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""The Python implementation of the gRPC route guide server."""
from concurrent import futures
import time
import math
import grpc
import route_guide_pb2
import route_guide_pb2_grpc
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.longitude / 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)
# Formula is based on http://mathforum.org/library/drmath/view/51879.html
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_grpc.RouteGuideServicer):
"""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 = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
route_guide_pb2_grpc.add_RouteGuideServicer_to_server(
RouteGuideServicer(), server)
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()
|
