add grpc example (#1401)

use grpc helloworld example.

Makefile

@@ -1,5 +1,6 @@
 GOFMT ?= gofmt "-s"
 PACKAGES ?= $(shell go list ./... | grep -v /vendor/)
+VETPACKAGES ?= $(shell go list ./... | grep -v /vendor/ | grep -v /examples/)
 GOFILES := $(shell find . -name "*.go" -type f -not -path "./vendor/*")
 
 all: install
@@ -26,7 +27,7 @@ fmt-check:
 	fi;
 
 vet:
-	go vet $(PACKAGES)
+	go vet $(VETPACKAGES)
 
 deps:
 	@hash govendor > /dev/null 2>&1; if [ $$? -ne 0 ]; then \

coverage.sh

@@ -4,7 +4,7 @@ set -e
 
 echo "mode: count" > coverage.out
 
-for d in $(go list ./... | grep -E 'gin$|binding$|render$'); do
+for d in $(go list ./... | grep -E 'gin$|binding$|render$' | grep -v 'examples'); do
     go test -v -covermode=count -coverprofile=profile.out $d
     if [ -f profile.out ]; then
         cat profile.out | grep -v "mode:" >> coverage.out

examples/grpc/README.md

@@ -0,0 +1,19 @@
+## How to run this example
+
+1. run grpc server
+
+```sh
+$ go run grpc/server.go
+```
+
+2. run gin server
+
+```sh
+$ go run gin/main.go
+```
+
+3. use curl command to test it
+
+```sh
+$ curl -v 'http://localhost:8052/rest/n/thinkerou'
+```

examples/grpc/gin/main.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"net/http"
+
+	"github.com/gin-gonic/gin"
+	pb "github.com/gin-gonic/gin/examples/grpc/pb"
+	"google.golang.org/grpc"
+)
+
+func main() {
+	// Set up a connection to the server.
+	conn, err := grpc.Dial("localhost:50051", grpc.WithInsecure())
+	if err != nil {
+		log.Fatalf("did not connect: %v", err)
+	}
+	defer conn.Close()
+	client := pb.NewGreeterClient(conn)
+
+	// Set up a http setver.
+	r := gin.Default()
+	r.GET("/rest/n/:name", func(c *gin.Context) {
+		name := c.Param("name")
+
+		// Contact the server and print out its response.
+		req := &pb.HelloRequest{Name: name}
+		res, err := client.SayHello(g, req)
+		if err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{
+				"error": err.Error(),
+			})
+			return
+		}
+
+		c.JSON(http.StatusOK, gin.H{
+			"result": fmt.Sprint(res.Message),
+		})
+	})
+
+	// Run http server
+	if err := r.Run(":8052"); err != nil {
+		log.Fatalf("could not run server: %v", err)
+	}
+}

examples/grpc/grpc/server.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"log"
+	"net"
+
+	pb "github.com/gin-gonic/gin/examples/grpc/pb"
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/reflection"
+)
+
+// server is used to implement helloworld.GreeterServer.
+type server struct{}
+
+// SayHello implements helloworld.GreeterServer
+func (s *server) SayHello(ctx context.Context, in *pb.HelloRequest) (*pb.HelloReply, error) {
+	return &pb.HelloReply{Message: "Hello " + in.Name}, nil
+}
+
+func main() {
+	lis, err := net.Listen("tcp", ":50051")
+	if err != nil {
+		log.Fatalf("failed to listen: %v", err)
+	}
+	s := grpc.NewServer()
+	pb.RegisterGreeterServer(s, &server{})
+
+	// Register reflection service on gRPC server.
+	reflection.Register(s)
+	if err := s.Serve(lis); err != nil {
+		log.Fatalf("failed to serve: %v", err)
+	}
+}

examples/grpc/pb/helloworld.pb.go

@@ -0,0 +1,151 @@
+// Code generated by protoc-gen-go.
+// source: helloworld.proto
+// DO NOT EDIT!
+
+/*
+Package helloworld is a generated protocol buffer package.
+
+It is generated from these files:
+	helloworld.proto
+
+It has these top-level messages:
+	HelloRequest
+	HelloReply
+*/
+package helloworld
+
+import 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 package
+
+// The request message containing the user's name.
+type HelloRequest struct {
+	Name string `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+}
+
+func (m *HelloRequest) Reset()                    { *m = HelloRequest{} }
+func (m *HelloRequest) String() string            { return proto.CompactTextString(m) }
+func (*HelloRequest) ProtoMessage()               {}
+func (*HelloRequest) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{0} }
+
+// The response message containing the greetings
+type HelloReply struct {
+	Message string `protobuf:"bytes,1,opt,name=message" json:"message,omitempty"`
+}
+
+func (m *HelloReply) Reset()                    { *m = HelloReply{} }
+func (m *HelloReply) String() string            { return proto.CompactTextString(m) }
+func (*HelloReply) ProtoMessage()               {}
+func (*HelloReply) Descriptor() ([]byte, []int) { return fileDescriptor0, []int{1} }
+
+func init() {
+	proto.RegisterType((*HelloRequest)(nil), "helloworld.HelloRequest")
+	proto.RegisterType((*HelloReply)(nil), "helloworld.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
+
+// Client API for Greeter service
+
+type GreeterClient interface {
+	// Sends a greeting
+	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 := grpc.Invoke(ctx, "/helloworld.Greeter/SayHello", in, out, c.cc, opts...)
+	if err != nil {
+		return nil, err
+	}
+	return out, nil
+}
+
+// Server API for Greeter service
+
+type GreeterServer interface {
+	// Sends a greeting
+	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: "/helloworld.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: "helloworld.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", fileDescriptor0) }
+
+var fileDescriptor0 = []byte{
+	// 174 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x09, 0x6e, 0x88, 0x02, 0xff, 0xe2, 0x12, 0xc8, 0x48, 0xcd, 0xc9,
+	0xc9, 0x2f, 0xcf, 0x2f, 0xca, 0x49, 0xd1, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0xe2, 0x42, 0x88,
+	0x28, 0x29, 0x71, 0xf1, 0x78, 0x80, 0x78, 0x41, 0xa9, 0x85, 0xa5, 0xa9, 0xc5, 0x25, 0x42, 0x42,
+	0x5c, 0x2c, 0x79, 0x89, 0xb9, 0xa9, 0x12, 0x8c, 0x0a, 0x8c, 0x1a, 0x9c, 0x41, 0x60, 0xb6, 0x92,
+	0x1a, 0x17, 0x17, 0x54, 0x4d, 0x41, 0x4e, 0xa5, 0x90, 0x04, 0x17, 0x7b, 0x6e, 0x6a, 0x71, 0x71,
+	0x62, 0x3a, 0x4c, 0x11, 0x8c, 0x6b, 0xe4, 0xc9, 0xc5, 0xee, 0x5e, 0x94, 0x9a, 0x5a, 0x92, 0x5a,
+	0x24, 0x64, 0xc7, 0xc5, 0x11, 0x9c, 0x58, 0x09, 0xd6, 0x25, 0x24, 0xa1, 0x87, 0xe4, 0x02, 0x64,
+	0xcb, 0xa4, 0xc4, 0xb0, 0xc8, 0x00, 0xad, 0x50, 0x62, 0x70, 0x32, 0xe0, 0x92, 0xce, 0xcc, 0xd7,
+	0x4b, 0x2f, 0x2a, 0x48, 0xd6, 0x4b, 0xad, 0x48, 0xcc, 0x2d, 0xc8, 0x49, 0x2d, 0x46, 0x52, 0xeb,
+	0xc4, 0x0f, 0x56, 0x1c, 0x0e, 0x62, 0x07, 0x80, 0xbc, 0x14, 0xc0, 0x98, 0xc4, 0x06, 0xf6, 0x9b,
+	0x31, 0x20, 0x00, 0x00, 0xff, 0xff, 0x0f, 0xb7, 0xcd, 0xf2, 0xef, 0x00, 0x00, 0x00,
+}

examples/grpc/pb/helloworld.proto

@@ -0,0 +1,37 @@
+// Copyright 2015 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.
+
+syntax = "proto3";
+
+option java_multiple_files = true;
+option java_package = "io.grpc.examples.helloworld";
+option java_outer_classname = "HelloWorldProto";
+
+package helloworld;
+
+// The greeting service definition.
+service Greeter {
+  // Sends a greeting
+  rpc SayHello (HelloRequest) returns (HelloReply) {}
+}
+
+// The request message containing the user's name.
+message HelloRequest {
+  string name = 1;
+}
+
+// The response message containing the greetings
+message HelloReply {
+  string message = 1;
+}