5.2.7 grpc验证器

1. 安装和配置

linux

# fetches this repo into $GOPATH
go get -d github.com/envoyproxy/protoc-gen-validate
# installs PGV into $GOPATH/bin
go build

windows

点此下载：protoc-gen-validate.zip

将 zip文件中的exe文件拷贝到 go的根补录的bin目录下

生成python源码

protoc -I .  --go_out=plugins=grpc:. --validate_out="lang=go:." helloworld.proto

2. proto

1. 新建validate.proto文件内容从 https://github.com/envoyproxy/protoc-gen-validate/blob/master/validate/validate.proto 拷贝
2. 新建helloworl.proto文件 ```protobuf syntax = “proto3”;

import “validate.proto”; option go_package=”.;proto”;

service Greeter { rpc SayHello (Person) returns (Person); }

message Person { uint64 id = 1 [(validate.rules).uint64.gt = 999];

string email = 2 [(validate.rules).string.email = true]; string name = 3 [(validate.rules).string = { pattern: “^[^[0-9]A-Za-z]+( [^[0-9]A-Za-z]+)*$”,max_bytes: 256,}];

}

<a name="zDJmx"></a>
## 3. 服务端（server）
```go
package main
import (
    "context"
    "google.golang.org/grpc/codes"
    "google.golang.org/grpc/status"
    "net"
    "google.golang.org/grpc"
    "start/pgv_test/proto"
)
type Server struct{}
func (s *Server) SayHello(ctx context.Context, request *proto.Person) (*proto.Person,
                                                                       error){
    return &proto.Person{
        Id: 32,
    }, nil
}
type Validator interface {
    Validate() error
}
func main(){
    var interceptor grpc.UnaryServerInterceptor
    interceptor = func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (resp interface{}, err error) {
        // 继续处理请求
        if r, ok := req.(Validator); ok {
            if err := r.Validate(); err != nil {
                return nil, status.Error(codes.InvalidArgument, err.Error())
            }
        }
        return handler(ctx, req)
    }
    var opts []grpc.ServerOption
    opts = append(opts, grpc.UnaryInterceptor(interceptor))
    g := grpc.NewServer(opts...)
    proto.RegisterGreeterServer(g, &Server{})
    lis, err := net.Listen("tcp", "0.0.0.0:50051")
    if err != nil{
        panic("failed to listen:"+err.Error())
    }
    err = g.Serve(lis)
    if err != nil{
        panic("failed to start grpc:"+err.Error())
    }
}

4. 客户端（client）

package  main
import (
    "context"
    "fmt"
    "google.golang.org/grpc"
    "start/pgv_test/proto"
)
type customCredential struct{}
func main() {
    var opts []grpc.DialOption
    //opts = append(opts, grpc.WithUnaryInterceptor(interceptor))
    opts = append(opts, grpc.WithInsecure())
    conn, err := grpc.Dial("localhost:50051", opts...)
    if err != nil {
        panic(err)
    }
    defer conn.Close()
    c := proto.NewGreeterClient(conn)
    //rsp, _ := c.Search(context.Background(), &empty.Empty{})
    rsp, err := c.SayHello(context.Background(), &proto.Person{
        Email: "bobby",
    })
    if err != nil {
        panic(err)
    }
    fmt.Println(rsp.Id)
}