ch4-05: 增加Grpc和Web共存内容

ch4-rpc/ch4-05-grpc-hack.md

@@ -316,11 +316,74 @@ func filter(
 
 不够GRPC框架中只能为每个服务设置一个截取器，因此所有对截取工作只能在一个函数中完成。不过开源的grpc-ecosystem项目中的go-grpc-middleware包已经基于GRPC对截取器实现了链式截取器的支持，感兴趣的同学可以参考。
 
-<!--
-
 ## 和Web服务共存
 
-TODO
+GRPC是构建在HTTP/2协议之上的，因此我们可以将GRPC服务和普通的Web服务架设在同一个端口之上。因为目前Go语言版本的GRPC实现还不够完善，只有启用了TLS协议之后才能将GRPC和Web服务运行在同一个端口。
+
+服务器证书的生成过程前文已经讲过，这么不再赘述。启用https的服务器非常简单：
+
+```go
+func main() {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
+		fmt.Fprintln(w, "hello")
+	})
+
+	http.ListenAndServeTLS(port, "server.crt", "server.key",
+		http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			mux.ServeHTTP(w, r)
+			return
+		}),
+	)
+}
+```
+
+而单独启用带证书的GRPC服务也是同样的简单：
+
+```go
+func main() {
+	creds, err := credentials.NewServerTLSFromFile("server.crt", "server.key")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	grpcServer := grpc.NewServer(grpc.Creds(creds))
+
+	...
+}
+```
+
+因为GRPC服务已经实现了ServeHTTP方法，可以直接作为Web路由处理对象。如果将Grpc和Web服务放在一起，会导致GRPC和Web路径的冲突，在处理时我们需要取分两个服务。
+
+首先GRPC是建立在HTTP/2版本之上，如果HTTP不是HTTP/2协议则必然无法提供GRPC支持。同时，如果每个GRPC调用请求的Content-Type类型会被标注为"application/grpc"类型。
+
+因此我们可以通过以下方式生成同时支持Web和Grpc协议的路由处理函数：
+
+```go
+func main() {
+	...
+
+	http.ListenAndServeTLS(port, "server.crt", "server.key",
+		http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			if r.ProtoMajor != 2 {
+				mux.ServeHTTP(w, r)
+				return
+			}
+			if strings.Contains(r.Header.Get("Content-Type"), "application/grpc") {
+				grpcServer.ServeHTTP(w, r) // GRPC Server
+				return
+			}
+
+			mux.ServeHTTP(w, r)
+			return
+		}),
+	)
+}
+```
+
+这样我们就可以在GRPC端口上同时提供Web服务了。
+
+<!--
 
 ## 导出Rest服务
 

vendor/gobook.examples/ch4-05-grpc-hack/on-web/Makefile

@@ -0,0 +1,10 @@
+
+run:
+	@go build -o a.out && ./a.out
+	-@rm ./a.out
+
+gen:
+	protoc -I . --go_out=plugins=grpc:. helloworld.proto
+
+clean:
+	-rm *.pb.go

vendor/gobook.examples/ch4-05-grpc-hack/on-web/helloworld.pb.go

@@ -0,0 +1,192 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// source: helloworld.proto
+
+package main
+
+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
+
+type 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.InternalMessageInfo
+
+func (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.InternalMessageInfo
+
+func (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 FileDescriptorProto
+	0x1f, 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,
+}

vendor/gobook.examples/ch4-05-grpc-hack/on-web/helloworld.proto

@@ -0,0 +1,15 @@
+syntax = "proto3";
+
+package main;
+
+service Greeter {
+	rpc SayHello (HelloRequest) returns (HelloReply);
+}
+
+message HelloRequest {
+	string name = 1;
+}
+
+message HelloReply {
+	string message = 1;
+}

vendor/gobook.examples/ch4-05-grpc-hack/on-web/main.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	fmt "fmt"
+	"log"
+	"net/http"
+	"strings"
+	"time"
+
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials"
+)
+
+var port = ":5000"
+
+type myGrpcServer struct{}
+
+func (s *myGrpcServer) SayHello(ctx context.Context, in *HelloRequest) (*HelloReply, error) {
+	return &HelloReply{Message: "Hello " + in.Name}, nil
+}
+
+func main() {
+	go startServer()
+	time.Sleep(time.Second)
+
+	doClientWork()
+}
+
+func startServer() {
+	creds, err := credentials.NewServerTLSFromFile("tls-config/server.crt", "tls-config/server.key")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	grpcServer := grpc.NewServer(grpc.Creds(creds))
+	RegisterGreeterServer(grpcServer, new(myGrpcServer))
+
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
+		fmt.Fprintln(w, "hello")
+	})
+
+	http.ListenAndServeTLS(port, "tls-config/server.crt", "tls-config/server.key", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// TODO(tamird): point to merged gRPC code rather than a PR.
+		// This is a partial recreation of gRPC's internal checks
+		// https://github.com/grpc/grpc-go/pull/514/files#diff-95e9a25b738459a2d3030e1e6fa2a718R61
+		if r.ProtoMajor == 2 && strings.Contains(r.Header.Get("Content-Type"), "application/grpc") {
+			grpcServer.ServeHTTP(w, r)
+		} else {
+			mux.ServeHTTP(w, r)
+		}
+	}))
+}
+
+func doClientWork() {
+	creds, err := credentials.NewClientTLSFromFile("tls-config/server.crt", "server.grpc.io")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	conn, err := grpc.Dial("localhost"+port, grpc.WithTransportCredentials(creds))
+	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)
+}

vendor/gobook.examples/ch4-05-grpc-hack/on-web/tls-config/Makefile

@@ -0,0 +1,10 @@
+
+default:
+	openssl genrsa -out server.key 2048
+	openssl req -new -x509 -days 3650 \
+		-subj "/C=GB/L=China/O=gobook/CN=server.grpc.io" \
+		-key server.key -out server.crt
+
+clean:
+	-rm *.key *.crt *.csr *.srl
+

vendor/gobook.examples/ch4-05-grpc-hack/on-web/tls-config/server.crt

@@ -0,0 +1,19 @@
+-----BEGIN CERTIFICATE-----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+-----END CERTIFICATE-----

vendor/gobook.examples/ch4-05-grpc-hack/on-web/tls-config/server.key

@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----