golang工程— grpc-gateway健康检查和跨域配置

grpc健康检查网关跨域配置

grpc健康检查

grpc健康检查使用

服务端配置

import (
    "google.golang.org/grpc/health"
    "google.golang.org/grpc/health/grpc_health_v1"
)

//添加健康检查服务,多路复用
grpc_health_v1.RegisterHealthServer(s, health.NewServer())

网关配置

gateway.go

package gateway

import (
    "context"
    "flag"
    "fmt"
    "google.golang.org/grpc/health/grpc_health_v1"
    "net/http"
    "user/user-server/gateway/middleware"

    "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
    "google.golang.org/grpc"
    "google.golang.org/grpc/credentials/insecure"
    _ "google.golang.org/grpc/grpclog"

    gw "user/proto"  // Update
)

var (
    // command-line options:
    // gRPC server endpoint
    grpcServerEndpoint = flag.String("grpc-server-endpoint",  "localhost:50051", "gRPC server endpoint")
)

func Run() error {
    ctx := context.Background()
    ctx, cancel := context.WithCancel(ctx)
    defer cancel()
    // 请求时,将http header中某些字段转发到grpc上下文
    inComingOpt :=  runtime.WithIncomingHeaderMatcher(func(s string) (string, bool) {
        fmt.Println("header:" + s)
        switch s {
        case "Service-Authorization":
            fmt.Println("Service-Authorization hit")
            return "Service-Authorization", true
        default:
            return "", false
        }
    })
    // 响应后,grpc上下文转发到http头部
    outGoingOpt := runtime.WithOutgoingHeaderMatcher(func(s string) (string, bool) {
       return "", false
    })


    //创建连接,用于健康检查
    conn, err := grpc.Dial(*grpcServerEndpoint, grpc.WithTransportCredentials(insecure.NewCredentials()))
    if err != nil {
        return err
    }


    // Register gRPC server endpoint
    // Note: Make sure the gRPC server is running properly and accessible
    // runtime.WithHealthEndpointAt() 指定路径， 转发Header到grpc上下文在这是不生效的inCommingOpt 是不生效的，因为我们在这弄了个客户端，需要手动转发操作。或者排除掉，我们这选择排除掉
    mux := runtime.NewServeMux(inComingOpt, outGoingOpt, runtime.WithHealthzEndpoint(grpc_health_v1.NewHealthClient(conn)))
    
    //添加文件上传处理函数
    mux.HandlePath("POST", "/upload", uploadHandler)
    handler := middleware.Cors(mux)
    opts := []grpc.DialOption{grpc.WithTransportCredentials(insecure.NewCredentials())}
    err = gw.RegisterUserHandlerFromEndpoint(ctx, mux,  *grpcServerEndpoint, opts)
    if err != nil {
        return err
    }

    // Start HTTP server (and proxy calls to gRPC server endpoint)
    return http.ListenAndServe(":8081", handler)
}

如果网关中设置了拦截器之类的进行鉴权判断，可以通过FullName="/grpc.health.v1.Health/Check"去忽略鉴权

监控检查默认请求 http://localhost:8081/healthz

grpc网关跨域配置

采用中间件的形式封装httphandler

package middleware

import "net/http"

func Cors(handler http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        method := r.Method
        origin := r.Header.Get("Origin")
        if origin != "" {
            // 允许来源配置
            w.Header().Set("Access-Control-Allow-Origin", "*") // 可将将 * 替换为指定的域名
            w.Header().Set("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE, UPDATE, PATCH")
            w.Header().Set("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, Authorization")
            w.Header().Set("Access-Control-Expose-Headers", "Content-Length, Access-Control-Allow-Origin, Access-Control-Allow-Headers, Cache-Control, Content-Language, Content-Type")
            w.Header().Set("Access-Control-Allow-Credentials", "true")
        }
        if method == "OPTIONS" {
            w.WriteHeader(http.StatusNoContent)
            return
        }
        handler.ServeHTTP(w, r)
    })
}

然后修改gateway

gateway.go

package gateway

import (
    "context"
    "flag"
    "fmt"
    "google.golang.org/grpc/health/grpc_health_v1"
    "net/http"
    "user/user-server/gateway/middleware"

    "github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
    "google.golang.org/grpc"
    "google.golang.org/grpc/credentials/insecure"
    _ "google.golang.org/grpc/grpclog"

    gw "user/proto"  // Update
)

var (
    // command-line options:
    // gRPC server endpoint
    grpcServerEndpoint = flag.String("grpc-server-endpoint",  "localhost:50051", "gRPC server endpoint")
)

func Run() error {
    ctx := context.Background()
    ctx, cancel := context.WithCancel(ctx)
    defer cancel()
    // 请求时,将http header中某些字段转发到grpc上下文
    inComingOpt :=  runtime.WithIncomingHeaderMatcher(func(s string) (string, bool) {
        fmt.Println("header:" + s)
        switch s {
        case "Service-Authorization":
            fmt.Println("Service-Authorization hit")
            return "Service-Authorization", true
        default:
            return "", false
        }
    })
    // 响应后,grpc上下文转发到http头部
    outGoingOpt := runtime.WithOutgoingHeaderMatcher(func(s string) (string, bool) {
       return "", false
    })


    //创建连接,用于健康检查
    conn, err := grpc.Dial(*grpcServerEndpoint, grpc.WithTransportCredentials(insecure.NewCredentials()))
    if err != nil {
        return err
    }


    // Register gRPC server endpoint
    // Note: Make sure the gRPC server is running properly and accessible
    // runtime.WithHealthEndpointAt() 指定路径， 转发Header到grpc上下文在这是不生效的inCommingOpt 是不生效的，因为我们在这弄了个客户端，需要手动转发操作。或者排除掉，我们这选择排除掉
    mux := runtime.NewServeMux(inComingOpt, outGoingOpt, runtime.WithHealthzEndpoint(grpc_health_v1.NewHealthClient(conn)))
    
    //添加文件上传处理函数
    mux.HandlePath("POST", "/upload", uploadHandler)
    handler := middleware.Cors(mux)
    opts := []grpc.DialOption{grpc.WithTransportCredentials(insecure.NewCredentials())}
    err = gw.RegisterUserHandlerFromEndpoint(ctx, mux,  *grpcServerEndpoint, opts)
    if err != nil {
        return err
    }

    // Start HTTP server (and proxy calls to gRPC server endpoint)
    return http.ListenAndServe(":8081", handler)
}

更多grpc跨域配置的内容见

[gin中间件编程与跨域配置](