xref: /aosp_15_r20/external/grpc-grpc/examples/cpp/route_guide/route_guide_server.cc (revision cc02d7e222339f7a4f6ba5f422e6413f4bd931f2)
1 /*
2  *
3  * Copyright 2015 gRPC authors.
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  *     http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  *
17  */
18 
19 #include <algorithm>
20 #include <chrono>
21 #include <cmath>
22 #include <iostream>
23 #include <memory>
24 #include <string>
25 
26 #include "helper.h"
27 
28 #include <grpc/grpc.h>
29 #include <grpcpp/security/server_credentials.h>
30 #include <grpcpp/server.h>
31 #include <grpcpp/server_builder.h>
32 #include <grpcpp/server_context.h>
33 #ifdef BAZEL_BUILD
34 #include "examples/protos/route_guide.grpc.pb.h"
35 #else
36 #include "route_guide.grpc.pb.h"
37 #endif
38 
39 using grpc::Server;
40 using grpc::ServerBuilder;
41 using grpc::ServerContext;
42 using grpc::ServerReader;
43 using grpc::ServerReaderWriter;
44 using grpc::ServerWriter;
45 using grpc::Status;
46 using routeguide::Feature;
47 using routeguide::Point;
48 using routeguide::Rectangle;
49 using routeguide::RouteGuide;
50 using routeguide::RouteNote;
51 using routeguide::RouteSummary;
52 using std::chrono::system_clock;
53 
ConvertToRadians(float num)54 float ConvertToRadians(float num) { return num * 3.1415926 / 180; }
55 
56 // The formula is based on http://mathforum.org/library/drmath/view/51879.html
GetDistance(const Point & start,const Point & end)57 float GetDistance(const Point& start, const Point& end) {
58   const float kCoordFactor = 10000000.0;
59   float lat_1 = start.latitude() / kCoordFactor;
60   float lat_2 = end.latitude() / kCoordFactor;
61   float lon_1 = start.longitude() / kCoordFactor;
62   float lon_2 = end.longitude() / kCoordFactor;
63   float lat_rad_1 = ConvertToRadians(lat_1);
64   float lat_rad_2 = ConvertToRadians(lat_2);
65   float delta_lat_rad = ConvertToRadians(lat_2 - lat_1);
66   float delta_lon_rad = ConvertToRadians(lon_2 - lon_1);
67 
68   float a = pow(sin(delta_lat_rad / 2), 2) +
69             cos(lat_rad_1) * cos(lat_rad_2) * pow(sin(delta_lon_rad / 2), 2);
70   float c = 2 * atan2(sqrt(a), sqrt(1 - a));
71   int R = 6371000;  // metres
72 
73   return R * c;
74 }
75 
GetFeatureName(const Point & point,const std::vector<Feature> & feature_list)76 std::string GetFeatureName(const Point& point,
77                            const std::vector<Feature>& feature_list) {
78   for (const Feature& f : feature_list) {
79     if (f.location().latitude() == point.latitude() &&
80         f.location().longitude() == point.longitude()) {
81       return f.name();
82     }
83   }
84   return "";
85 }
86 
87 class RouteGuideImpl final : public RouteGuide::Service {
88  public:
RouteGuideImpl(const std::string & db)89   explicit RouteGuideImpl(const std::string& db) {
90     routeguide::ParseDb(db, &feature_list_);
91   }
92 
GetFeature(ServerContext * context,const Point * point,Feature * feature)93   Status GetFeature(ServerContext* context, const Point* point,
94                     Feature* feature) override {
95     feature->set_name(GetFeatureName(*point, feature_list_));
96     feature->mutable_location()->CopyFrom(*point);
97     return Status::OK;
98   }
99 
ListFeatures(ServerContext * context,const routeguide::Rectangle * rectangle,ServerWriter<Feature> * writer)100   Status ListFeatures(ServerContext* context,
101                       const routeguide::Rectangle* rectangle,
102                       ServerWriter<Feature>* writer) override {
103     auto lo = rectangle->lo();
104     auto hi = rectangle->hi();
105     long left = (std::min)(lo.longitude(), hi.longitude());
106     long right = (std::max)(lo.longitude(), hi.longitude());
107     long top = (std::max)(lo.latitude(), hi.latitude());
108     long bottom = (std::min)(lo.latitude(), hi.latitude());
109     for (const Feature& f : feature_list_) {
110       if (f.location().longitude() >= left &&
111           f.location().longitude() <= right &&
112           f.location().latitude() >= bottom && f.location().latitude() <= top) {
113         writer->Write(f);
114       }
115     }
116     return Status::OK;
117   }
118 
RecordRoute(ServerContext * context,ServerReader<Point> * reader,RouteSummary * summary)119   Status RecordRoute(ServerContext* context, ServerReader<Point>* reader,
120                      RouteSummary* summary) override {
121     Point point;
122     int point_count = 0;
123     int feature_count = 0;
124     float distance = 0.0;
125     Point previous;
126 
127     system_clock::time_point start_time = system_clock::now();
128     while (reader->Read(&point)) {
129       point_count++;
130       if (!GetFeatureName(point, feature_list_).empty()) {
131         feature_count++;
132       }
133       if (point_count != 1) {
134         distance += GetDistance(previous, point);
135       }
136       previous = point;
137     }
138     system_clock::time_point end_time = system_clock::now();
139     summary->set_point_count(point_count);
140     summary->set_feature_count(feature_count);
141     summary->set_distance(static_cast<long>(distance));
142     auto secs =
143         std::chrono::duration_cast<std::chrono::seconds>(end_time - start_time);
144     summary->set_elapsed_time(secs.count());
145 
146     return Status::OK;
147   }
148 
RouteChat(ServerContext * context,ServerReaderWriter<RouteNote,RouteNote> * stream)149   Status RouteChat(ServerContext* context,
150                    ServerReaderWriter<RouteNote, RouteNote>* stream) override {
151     RouteNote note;
152     while (stream->Read(&note)) {
153       std::unique_lock<std::mutex> lock(mu_);
154       for (const RouteNote& n : received_notes_) {
155         if (n.location().latitude() == note.location().latitude() &&
156             n.location().longitude() == note.location().longitude()) {
157           stream->Write(n);
158         }
159       }
160       received_notes_.push_back(note);
161     }
162 
163     return Status::OK;
164   }
165 
166  private:
167   std::vector<Feature> feature_list_;
168   std::mutex mu_;
169   std::vector<RouteNote> received_notes_;
170 };
171 
RunServer(const std::string & db_path)172 void RunServer(const std::string& db_path) {
173   std::string server_address("0.0.0.0:50051");
174   RouteGuideImpl service(db_path);
175 
176   ServerBuilder builder;
177   builder.AddListeningPort(server_address, grpc::InsecureServerCredentials());
178   builder.RegisterService(&service);
179   std::unique_ptr<Server> server(builder.BuildAndStart());
180   std::cout << "Server listening on " << server_address << std::endl;
181   server->Wait();
182 }
183 
main(int argc,char ** argv)184 int main(int argc, char** argv) {
185   // Expect only arg: --db_path=path/to/route_guide_db.json.
186   std::string db = routeguide::GetDbFileContent(argc, argv);
187   RunServer(db);
188 
189   return 0;
190 }
191