vendor/google.golang.org/grpc/health/health.go

   1 /*
   2  *
   3  * Copyright 2017 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 // Package health provides some utility functions to health-check a server. The implementation
  20 // is based on protobuf. Users need to write their own implementations if other IDLs are used.
  21 package health
  22
  23 import (
  24         "sync"
  25
  26         "golang.org/x/net/context"
  27         "google.golang.org/grpc"
  28         "google.golang.org/grpc/codes"
  29         healthpb "google.golang.org/grpc/health/grpc_health_v1"
  30 )
  31
  32 // Server implements `service Health`.
  33 type Server struct {
  34         mu sync.Mutex
  35         // statusMap stores the serving status of the services this Server monitors.
  36         statusMap map[string]healthpb.HealthCheckResponse_ServingStatus
  37 }
  38
  39 // NewServer returns a new Server.
  40 func NewServer() *Server {
  41         return &Server{
  42                 statusMap: make(map[string]healthpb.HealthCheckResponse_ServingStatus),
  43         }
  44 }
  45
  46 // Check implements `service Health`.
  47 func (s *Server) Check(ctx context.Context, in *healthpb.HealthCheckRequest) (*healthpb.HealthCheckResponse, error) {
  48         s.mu.Lock()
  49         defer s.mu.Unlock()
  50         if in.Service == "" {
  51                 // check the server overall health status.
  52                 return &healthpb.HealthCheckResponse{
  53                         Status: healthpb.HealthCheckResponse_SERVING,
  54                 }, nil
  55         }
  56         if status, ok := s.statusMap[in.Service]; ok {
  57                 return &healthpb.HealthCheckResponse{
  58                         Status: status,
  59                 }, nil
  60         }
  61         return nil, grpc.Errorf(codes.NotFound, "unknown service")
  62 }
  63
  64 // SetServingStatus is called when need to reset the serving status of a service
  65 // or insert a new service entry into the statusMap.
  66 func (s *Server) SetServingStatus(service string, status healthpb.HealthCheckResponse_ServingStatus) {
  67         s.mu.Lock()
  68         s.statusMap[service] = status
  69         s.mu.Unlock()
  70 }