golang 工程组件 grpc-gateway—yaml定义http规则，和自定义实现网关路由

yaml定义http规则，和自定义实现网关路由

proto定义http规则总归是麻烦的，因为proto文件还是定义消息，grpc接口好一些。配置http规则有更好的方式。我们可以使用yaml文件定义接口的http规则。同时有些接口不是只是让网关转发这么简单有时需要自己定网关接口handler

yaml定义http规则

type: google.api.Service
config_version: 3http:rules:# {package}.{message}.{method}- selector: user.User.Getget: "/user/{id}"- selector: user.User.AddOrUpdatepost: "/user"body: "*"additional_bindings:- put: "/user"body: "*"- patch: "/user"body: "addr"- selector: user.User.Deletedelete: "/user/{id}"

proto文件

syntax = "proto3";
package  user;
option go_package = "user/proto";message Member{int64 id = 1;string userName = 2[json_name = "user_name"];int32 age = 3;string phone = 4;Addr addr = 5;
}
message Addr {string province = 1;string city = 2;string county = 3;
}message UploadRequest {int64  size = 1;bytes content = 2;
}
message UploadResponse {string filePath= 1[json_name = "file_path"];
}
service User{rpc Get(Member) returns (Member) {}rpc AddOrUpdate(Member) returns (Member) { }rpc Delete(Member) returns (Member) {}rpc Upload(stream UploadRequest) returns (UploadResponse){}
}

生成消息,grpc,网关

# 生成message 
protoc --proto_path=proto --go_out=proto --go_opt=paths=source_relative proto/user.proto 
# 生成grpc service 
protoc --proto_path=proto --go-grpc_out=proto --go-grpc_opt=paths=source_relative proto/user.proto
#生成gateway
protoc --proto_path=proto  --grpc-gateway_out=proto  --grpc-gateway_opt logtostderr=true  --grpc-gateway_opt paths=source_relative  --grpc-gateway_opt grpc_api_configuration=proto/user.yaml  proto/user.proto

参考grpc-gateway入门中的启动代码就能调用对应接口啦

自定义实现网关路由

在生成gateway后，前面proto文件中我们预留了一个文件上传grpc接口。然后在yaml中我们是没有定义对应http规则。所以需要自定义实现对应的网关路由，来应对复杂的业务情况。

gateway.go

通过mux.HandlePath添加自定义处理的路由和对应handler函数

package gatewayimport ("context""flag""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"gw "user/proto"
)var (grpcServerEndpoint = flag.String("grpc-server-endpoint", "localhost:50051", "gRPC server endpoint")
)func Run() error {ctx := context.Background()ctx, cancel := context.WithCancel(ctx)defer cancel()inComingOpt := runtime.WithIncomingHeaderMatcher(func(s string) (string, bool) {switch s {case "Service-Authorization":return "service-authorization", truedefault:return "", false}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}mux := runtime.NewServeMux(inComingOpt, runtime.WithHealthzEndpoint(grpc_health_v1.NewHealthClient(conn)))//添加自定义处理函数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}return http.ListenAndServe(":8081", handler)
}

upload.go

写对应网关需要注册的handler

package gatewayimport ("context""fmt""github.com/golang/protobuf/jsonpb""google.golang.org/grpc""google.golang.org/grpc/credentials/insecure""google.golang.org/grpc/metadata""io""net/http""user/proto"
)func uploadHandler(w http.ResponseWriter, r *http.Request, pathParams map[string]string) {serviceAuthorization := r.Header.Get("Service-Authorization")fmt.Println(serviceAuthorization)err := r.ParseForm()if err != nil {http.Error(w, fmt.Sprintf("上传失败：%s", err.Error()), http.StatusInternalServerError)return}f, header, err := r.FormFile("attachment")if err != nil {http.Error(w, fmt.Sprintf("上传失败：%s", err.Error()), http.StatusInternalServerError)return}defer f.Close()conn, err := grpc.Dial(*grpcServerEndpoint, grpc.WithTransportCredentials(insecure.NewCredentials()))if err != nil {http.Error(w, fmt.Sprintf("上传失败：%s", err.Error()), http.StatusInternalServerError)return}defer conn.Close()c := proto.NewUserClient(conn)ctx := context.Background()ctx = metadata.NewOutgoingContext(ctx, metadata.New(map[string]string{"file_name": header.Filename, "service-authorization": serviceAuthorization}))stream, err := c.Upload(ctx)if err != nil {http.Error(w, fmt.Sprintf("上传失败：%s", err.Error()), http.StatusInternalServerError)return}buf := make([]byte, 100)for {n, err := f.Read(buf)if err != nil && err != io.EOF {http.Error(w, fmt.Sprintf("上传失败：%s", err.Error()), http.StatusInternalServerError)return}if n == 0 {break}stream.Send(&proto.UploadRequest{Content: buf[:n],Size:    int64(n),})}res, err := stream.CloseAndRecv()if err != nil {http.Error(w, fmt.Sprintf("上传失败：%s", err.Error()), http.StatusInternalServerError)return}m := jsonpb.Marshaler{}str, err := m.MarshalToString(res)if err != nil {http.Error(w, fmt.Sprintf("上传失败：%s", err.Error()), http.StatusInternalServerError)return}w.Header().Add("Content-Type", "application/json")fmt.Fprint(w, str)
}