xref: /aosp_15_r20/external/grpc-grpc/test/cpp/util/metrics_server.h (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 // is % allowed in string
17 //
18 #ifndef GRPC_TEST_CPP_UTIL_METRICS_SERVER_H
19 #define GRPC_TEST_CPP_UTIL_METRICS_SERVER_H
20 
21 #include <map>
22 #include <mutex>
23 
24 #include <grpcpp/server.h>
25 
26 #include "src/proto/grpc/testing/metrics.grpc.pb.h"
27 #include "src/proto/grpc/testing/metrics.pb.h"
28 
29 //
30 // This implements a Metrics server defined in
31 // src/proto/grpc/testing/metrics.proto. Any
32 // test service can use this to export Metrics (TODO (sreek): Only Gauges for
33 // now).
34 //
35 // Example:
36 //    MetricsServiceImpl metricsImpl;
37 //    ..
38 //    // Create QpsGauge(s). Note: QpsGauges can be created even after calling
39 //    // 'StartServer'.
40 //    QpsGauge qps_gauge1 = metricsImpl.CreateQpsGauge("foo", is_present);
41 //    // qps_gauge1 can now be used anywhere in the program by first making a
42 //    // one-time call qps_gauge1.Reset() and then calling qps_gauge1.Incr()
43 //    // every time to increment a query counter
44 //
45 //    ...
46 //    // Create the metrics server
47 //    std::unique_ptr<grpc::Server> server = metricsImpl.StartServer(port);
48 //    server->Wait(); // Note: This is blocking.
49 //
50 namespace grpc {
51 namespace testing {
52 
53 class QpsGauge {
54  public:
55   QpsGauge();
56 
57   // Initialize the internal timer and reset the query count to 0
58   void Reset();
59 
60   // Increment the query count by 1
61   void Incr();
62 
63   // Return the current qps (i.e query count divided by the time since this
64   // QpsGauge object created (or Reset() was called))
65   long Get();
66 
67  private:
68   gpr_timespec start_time_;
69   long num_queries_;
70   std::mutex num_queries_mu_;
71 };
72 
73 class MetricsServiceImpl final : public MetricsService::Service {
74  public:
75   grpc::Status GetAllGauges(ServerContext* context, const EmptyMessage* request,
76                             ServerWriter<GaugeResponse>* writer) override;
77 
78   grpc::Status GetGauge(ServerContext* context, const GaugeRequest* request,
79                         GaugeResponse* response) override;
80 
81   // Create a QpsGauge with name 'name'. is_present is set to true if the Gauge
82   // is already present in the map.
83   // NOTE: CreateQpsGauge can be called anytime (i.e before or after calling
84   // StartServer).
85   std::shared_ptr<QpsGauge> CreateQpsGauge(const std::string& name,
86                                            bool* already_present);
87 
88   std::unique_ptr<grpc::Server> StartServer(int port);
89 
90  private:
91   std::map<string, std::shared_ptr<QpsGauge>> qps_gauges_;
92   std::mutex mu_;
93 };
94 
95 }  // namespace testing
96 }  // namespace grpc
97 
98 #endif  // GRPC_TEST_CPP_UTIL_METRICS_SERVER_H
99