如何实施grpc-go健康检查？

Question

我正在寻找grpc-go健康检查的文档和代码示例。

寻找问题

• https://github.com/grpc/grpc-go/issues/448
• https://github.com/grpc/grpc-go/issues/2770

没有明确的答案，我可以重新使用在我的程序中实施健康检查。

Answer 1

我建议您查看此Github项目，以了解如何构建为生产准备的gRPC服务，其中包括健康检查等。

特定于健康检查，您可以检查它是如何完成的，这里

库利用了这个更专注的项目

如果您不想使用lib，您可以像这样实现健康检查：

import (
    "google.golang.org/grpc/health"
    "google.golang.org/grpc/health/grpc_health_v1"
)
grpcServer := grpc.NewServer()
grpc_health_v1.RegisterHealthServer(grpcServer, health.NewServer())

Answer 2

你发布的其中一个链接有一个链接到这个read：https://github.com/grpc/grpc/blob/master/doc/health-checking.md

现在您应该实现该逻辑，并在您的服务集合中注册该服务。

readme建议手动将服务注册到健康检查服务中，这样您就可以传递服务列表作为参数来创建健康检查服务。

我建议为您的服务定义一个接口，以便健康检查服务可以以同样的方式处理所有这些服务：

type HealthMeter interface {
    GetHealth() mysample.HealthCheckResponse_ServingStatus
    WatchHealth() <- chan mysample.HealthCheckResponse_ServingStatus
}

// implement service "A" and "B" as both interfaces (gRPC server AND HealthMeter)

grpcServer := grpc.NewServer()
srvA := servers.NewServiceA()
srvB := servers.NewServiceB()
healthSrv := servers.NewHealthCheckServer(map[string]servers.HealthMeter{
    "serviceA": srvA,
    "serviceB": srvB,
})

mysample.RegisterServiceAServer(grpcServer, srvA)
mysample.RegisterServiceBServer(grpcServer, srvB)
mysample.RegisterHealthServer(grpcServer, healthSrv)

我希望它能帮到你。

Answer 3

在grpc包中实现健康检查示例的最简单方法

/*
 *
 * Copyright 2020 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.
 *
 */

// Binary server is an example server.
package main

import (
    "context"
    "flag"
    "fmt"
    "log"
    "net"
    "time"

    "google.golang.org/grpc"
    pb "google.golang.org/grpc/examples/features/proto/echo"
    "google.golang.org/grpc/health"
    healthgrpc "google.golang.org/grpc/health/grpc_health_v1"
    healthpb "google.golang.org/grpc/health/grpc_health_v1"
)

var (
    port  = flag.Int("port", 50051, "the port to serve on")
    sleep = flag.Duration("sleep", time.Second*5, "duration between changes in health")

    system = "" // empty string represents the health of the system
)

type echoServer struct {
    pb.UnimplementedEchoServer
}

func (e *echoServer) UnaryEcho(ctx context.Context, req *pb.EchoRequest) (*pb.EchoResponse, error) {
    return &pb.EchoResponse{
        Message: fmt.Sprintf("hello from localhost:%d", *port),
    }, nil
}

var _ pb.EchoServer = &echoServer{}

func main() {
    flag.Parse()

    lis, err := net.Listen("tcp", fmt.Sprintf(":%d", *port))
    if err != nil {
        log.Fatalf("failed to listen: %v", err)
    }

    s := grpc.NewServer()
    healthcheck := health.NewServer()
    healthgrpc.RegisterHealthServer(s, healthcheck)
    pb.RegisterEchoServer(s, &echoServer{})

    go func() {
        // asynchronously inspect dependencies and toggle serving status as needed
        next := healthpb.HealthCheckResponse_SERVING

        for {
            healthcheck.SetServingStatus(system, next)

            if next == healthpb.HealthCheckResponse_SERVING {
                next = healthpb.HealthCheckResponse_NOT_SERVING
            } else {
                next = healthpb.HealthCheckResponse_SERVING
            }

            time.Sleep(*sleep)
        }
    }()

    if err := s.Serve(lis); err != nil {
        log.Fatalf("failed to serve: %v", err)
    }
}