概述
kubernetes本身不支持gRPC健康检查，本文记录使用 ‘grpc-health-probe’ 实现grpc服务的健康检查
‘grpc-health-probe’，这是 Kubernetes 原生的健康检查 gRPC 应用程序的方法

官方参考文档：https://kubernetes.io/zh-cn/blog/2018/10/01/health-checking-grpc-servers-on-kubernetes/

示例

• 下载grpc-health-probe文件
  按需下载指定版本grpc-health-probe文件

  下载地址：https://github.com/grpc-ecosystem/grpc-health-probe/releases

• 配置grpc-health-probe
  将静态编译的grpc_health_probe打在容器映像中
  Dockerfile：

  COPY ocr/data/grpc_health_probe_v0.4.1 /bin/grpc_health_probeRUN chmod +x /bin/grpc_health_probe
  

• 健康检查接口实现

  • 创建health.proto文件

  syntax = "proto3";// 定义grpc请求消息体
  message HealthCheckRequest {string service = 1;
  }// 定义grpc返回消息体
  message HealthCheckResponse {enum ServingStatus {UNKNOWN = 0;SERVING = 1;NOT_SERVING = 2;}ServingStatus status = 1;
  }// 定义服务接口
  service Health {rpc Check(HealthCheckRequest) returns (HealthCheckResponse);
  }
  

  • 健康检查接口实现

   class HealthServer(health_pb2_grpc.HealthServicer):"""定义类继承HealthServicer"""def __init__(self):passdef Check(self, request, context):"""健康检查接口，实现proto文件中的服务接口"""return health_pb2.HealthCheckResponse(status=HealthCheckResponse.ServingStatus.SERVING)def run(host, port):"""运行ocr服务:param host::param port::return:"""server = grpc.server(futures.ThreadPoolExecutor(max_workers=5))health_pb2_grpc.add_HealthServicer_to_server(HealthServer(), server)server.add_insecure_port(f'{host}:{port}')server.start()print('Grpc server connect successful!')# 启动服务，等待退出try:while True:time.sleep(600)except KeyboardInterrupt:server.stop(0)if __name__ == '__main__':run(host='0.0.0.0', port='8001')
  

  • 容器中测试

  \bin\grpc-health-probe -addr :8001
  返回 SERVING
  

  • kubernetes中配置

  spec:containers:- name: serverimage: "[YOUR-DOCKER-IMAGE]"ports:- containerPort: 8001readinessProbe:exec:command: ["/bin/grpc_health_probe", "-addr=:8001"]initialDelaySeconds: 5livenessProbe:exec:command: ["/bin/grpc_health_probe", "-addr=:8001"]initialDelaySeconds: 10
  

参考文档：
grpc_health_probe配置：https://github.com/grpc-ecosystem/grpc-health-probe/