《GO语言高级编程》设计中案例，仅作为笔记进行收藏。基于证书的认证是针对每个gRPC链接的认证。gRPC还为每个gRPC⽅法调⽤提供了认证⽀持，基于⽤户Token对不同的⽅法访问进⾏权限管理。

1.helloworld.proto

syntax = "proto3";package main;service Greeter{rpc SayHello(HelloRequest) returns (HelloReply);
}message HelloRequest{string name = 1;
}message HelloReply{string message = 1;
}

2.helloworld.pb.go

// Code generated by protoc-gen-go. DO NOT EDIT.
// source: helloworld.protopackage mainimport proto "github.com/golang/protobuf/proto"
import fmt "fmt"
import math "math"import (context "golang.org/x/net/context"grpc "google.golang.org/grpc"
)// Reference imports to suppress errors if they are not otherwise used.
var _ = proto.Marshal
var _ = fmt.Errorf
var _ = math.Inf// This is a compile-time assertion to ensure that this generated file
// is compatible with the proto package it is being compiled against.
// A compilation error at this line likely means your copy of the
// proto package needs to be updated.
const _ = proto.ProtoPackageIsVersion2 // please upgrade the proto packagetype HelloRequest struct {Name                 string   `protobuf:"bytes,1,opt,name=name,proto3" json:"name,omitempty"`XXX_NoUnkeyedLiteral struct{} `json:"-"`XXX_unrecognized     []byte   `json:"-"`XXX_sizecache        int32    `json:"-"`
}func (m *HelloRequest) Reset()         { *m = HelloRequest{} }
func (m *HelloRequest) String() string { return proto.CompactTextString(m) }
func (*HelloRequest) ProtoMessage()    {}
func (*HelloRequest) Descriptor() ([]byte, []int) {return fileDescriptor_helloworld_04dfe859c9b956ba, []int{0}
}
func (m *HelloRequest) XXX_Unmarshal(b []byte) error {return xxx_messageInfo_HelloRequest.Unmarshal(m, b)
}
func (m *HelloRequest) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {return xxx_messageInfo_HelloRequest.Marshal(b, m, deterministic)
}
func (dst *HelloRequest) XXX_Merge(src proto.Message) {xxx_messageInfo_HelloRequest.Merge(dst, src)
}
func (m *HelloRequest) XXX_Size() int {return xxx_messageInfo_HelloRequest.Size(m)
}
func (m *HelloRequest) XXX_DiscardUnknown() {xxx_messageInfo_HelloRequest.DiscardUnknown(m)
}var xxx_messageInfo_HelloRequest proto.InternalMessageInfofunc (m *HelloRequest) GetName() string {if m != nil {return m.Name}return ""
}type HelloReply struct {Message              string   `protobuf:"bytes,1,opt,name=message,proto3" json:"message,omitempty"`XXX_NoUnkeyedLiteral struct{} `json:"-"`XXX_unrecognized     []byte   `json:"-"`XXX_sizecache        int32    `json:"-"`
}func (m *HelloReply) Reset()         { *m = HelloReply{} }
func (m *HelloReply) String() string { return proto.CompactTextString(m) }
func (*HelloReply) ProtoMessage()    {}
func (*HelloReply) Descriptor() ([]byte, []int) {return fileDescriptor_helloworld_04dfe859c9b956ba, []int{1}
}
func (m *HelloReply) XXX_Unmarshal(b []byte) error {return xxx_messageInfo_HelloReply.Unmarshal(m, b)
}
func (m *HelloReply) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {return xxx_messageInfo_HelloReply.Marshal(b, m, deterministic)
}
func (dst *HelloReply) XXX_Merge(src proto.Message) {xxx_messageInfo_HelloReply.Merge(dst, src)
}
func (m *HelloReply) XXX_Size() int {return xxx_messageInfo_HelloReply.Size(m)
}
func (m *HelloReply) XXX_DiscardUnknown() {xxx_messageInfo_HelloReply.DiscardUnknown(m)
}var xxx_messageInfo_HelloReply proto.InternalMessageInfofunc (m *HelloReply) GetMessage() string {if m != nil {return m.Message}return ""
}func init() {proto.RegisterType((*HelloRequest)(nil), "main.HelloRequest")proto.RegisterType((*HelloReply)(nil), "main.HelloReply")
}// Reference imports to suppress errors if they are not otherwise used.
var _ context.Context
var _ grpc.ClientConn// This is a compile-time assertion to ensure that this generated file
// is compatible with the grpc package it is being compiled against.
const _ = grpc.SupportPackageIsVersion4// GreeterClient is the client API for Greeter service.
//
// For semantics around ctx use and closing/ending streaming RPCs, please refer to https://godoc.org/google.golang.org/grpc#ClientConn.NewStream.
type GreeterClient interface {SayHello(ctx context.Context, in *HelloRequest, opts ...grpc.CallOption) (*HelloReply, error)
}type greeterClient struct {cc *grpc.ClientConn
}func NewGreeterClient(cc *grpc.ClientConn) GreeterClient {return &greeterClient{cc}
}func (c *greeterClient) SayHello(ctx context.Context, in *HelloRequest, opts ...grpc.CallOption) (*HelloReply, error) {out := new(HelloReply)err := c.cc.Invoke(ctx, "/main.Greeter/SayHello", in, out, opts...)if err != nil {return nil, err}return out, nil
}// GreeterServer is the server API for Greeter service.
type GreeterServer interface {SayHello(context.Context, *HelloRequest) (*HelloReply, error)
}func RegisterGreeterServer(s *grpc.Server, srv GreeterServer) {s.RegisterService(&_Greeter_serviceDesc, srv)
}func _Greeter_SayHello_Handler(srv interface{}, ctx context.Context, dec func(interface{}) error, interceptor grpc.UnaryServerInterceptor) (interface{}, error) {in := new(HelloRequest)if err := dec(in); err != nil {return nil, err}if interceptor == nil {return srv.(GreeterServer).SayHello(ctx, in)}info := &grpc.UnaryServerInfo{Server:     srv,FullMethod: "/main.Greeter/SayHello",}handler := func(ctx context.Context, req interface{}) (interface{}, error) {return srv.(GreeterServer).SayHello(ctx, req.(*HelloRequest))}return interceptor(ctx, in, info, handler)
}var _Greeter_serviceDesc = grpc.ServiceDesc{ServiceName: "main.Greeter",HandlerType: (*GreeterServer)(nil),Methods: []grpc.MethodDesc{{MethodName: "SayHello",Handler:    _Greeter_SayHello_Handler,},},Streams:  []grpc.StreamDesc{},Metadata: "helloworld.proto",
}func init() { proto.RegisterFile("helloworld.proto", fileDescriptor_helloworld_04dfe859c9b956ba) }var fileDescriptor_helloworld_04dfe859c9b956ba = []byte{// 142 bytes of a gzipped FileDescriptorProto0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0x12, 0xc8, 0x48, 0xcd, 0xc9,0xc9, 0x2f, 0xcf, 0x2f, 0xca, 0x49, 0xd1, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0x62, 0xc9, 0x4d,0xcc, 0xcc, 0x53, 0x52, 0xe2, 0xe2, 0xf1, 0x00, 0xc9, 0x04, 0xa5, 0x16, 0x96, 0xa6, 0x16, 0x97,0x08, 0x09, 0x71, 0xb1, 0xe4, 0x25, 0xe6, 0xa6, 0x4a, 0x30, 0x2a, 0x30, 0x6a, 0x70, 0x06, 0x81,0xd9, 0x4a, 0x6a, 0x5c, 0x5c, 0x50, 0x35, 0x05, 0x39, 0x95, 0x42, 0x12, 0x5c, 0xec, 0xb9, 0xa9,0xc5, 0xc5, 0x89, 0xe9, 0x30, 0x45, 0x30, 0xae, 0x91, 0x35, 0x17, 0xbb, 0x7b, 0x51, 0x6a, 0x6a,0x49, 0x6a, 0x91, 0x90, 0x01, 0x17, 0x47, 0x70, 0x62, 0x25, 0x58, 0x97, 0x90, 0x90, 0x1e, 0xc8,0x26, 0x3d, 0x64, 0x6b, 0xa4, 0x04, 0x50, 0xc4, 0x0a, 0x72, 0x2a, 0x93, 0xd8, 0xc0, 0xae, 0x32,0x06, 0x04, 0x00, 0x00, 0xff, 0xff, 0x18, 0x38, 0x13, 0xf1, 0xa9, 0x00, 0x00, 0x00,
}

3.main.go

package mainimport (fmt "fmt""log""net""time""golang.org/x/net/context""google.golang.org/grpc""google.golang.org/grpc/codes""google.golang.org/grpc/metadata"
)var (port = ":5000"
)type myGrpcServer struct{}func (s *myGrpcServer) SayHello(ctx context.Context, in *HelloRequest) (*HelloReply, error) {md, ok := metadata.FromIncomingContext(ctx)if !ok {return nil, fmt.Errorf("missing credentials")}var (appid  stringappkey string)if val, ok := md["login"]; ok {appid = val[0]}if val, ok := md["password"]; ok {appkey = val[0]}if appid != "gopher" || appkey != "password" {return nil, grpc.Errorf(codes.Unauthenticated, "invalid token: appid=%s, appkey=%s", appid, appkey)}return &HelloReply{Message: "Hello " + in.Name}, nil
}// 实现grpc.PerRPCCredentials接⼝
type Authentication struct {Login    stringPassword string
}func (a *Authentication) GetRequestMetadata(context.Context, ...string) (map[string]string, error) {return map[string]string{"login": a.Login, "password": a.Password}, nil
}
func (a *Authentication) RequireTransportSecurity() bool {return false
}func main() {go startServer()time.Sleep(time.Second)doClientWork()
}func startServer() {server := grpc.NewServer()RegisterGreeterServer(server, new(myGrpcServer))lis, err := net.Listen("tcp", port)if err != nil {log.Panicf("could not list on %s: %s", port, err)}if err := server.Serve(lis); err != nil {log.Panicf("grpc serve error: %s", err)}
}func doClientWork() {auth := Authentication{Login:    "gopher",Password: "password",}conn, err := grpc.Dial("localhost"+port, grpc.WithInsecure(), grpc.WithPerRPCCredentials(&auth))if err != nil {log.Fatal(err)}defer conn.Close()c := NewGreeterClient(conn)r, err := c.SayHello(context.Background(), &HelloRequest{Name: "gopher"})if err != nil {log.Fatalf("could not greet: %v", err)}log.Printf("doClientWork: %s", r.Message)
}