add examples/errors (#1077)

* addd examples/errors

examples/errors/api/error_reason.pb.go

@@ -0,0 +1,136 @@
+// Code generated by protoc-gen-go. DO NOT EDIT.
+// versions:
+// 	protoc-gen-go v1.26.0
+// 	protoc        v3.17.1
+// source: error_reason.proto
+
+package api
+
+import (
+	_ "github.com/go-kratos/kratos/v2/errors"
+	protoreflect "google.golang.org/protobuf/reflect/protoreflect"
+	protoimpl "google.golang.org/protobuf/runtime/protoimpl"
+	reflect "reflect"
+	sync "sync"
+)
+
+const (
+	// Verify that this generated code is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(20 - protoimpl.MinVersion)
+	// Verify that runtime/protoimpl is sufficiently up-to-date.
+	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
+)
+
+type ErrorReason int32
+
+const (
+	ErrorReason_USER_NOT_FOUND  ErrorReason = 0
+	ErrorReason_CONTENT_MISSING ErrorReason = 1
+)
+
+// Enum value maps for ErrorReason.
+var (
+	ErrorReason_name = map[int32]string{
+		0: "USER_NOT_FOUND",
+		1: "CONTENT_MISSING",
+	}
+	ErrorReason_value = map[string]int32{
+		"USER_NOT_FOUND":  0,
+		"CONTENT_MISSING": 1,
+	}
+)
+
+func (x ErrorReason) Enum() *ErrorReason {
+	p := new(ErrorReason)
+	*p = x
+	return p
+}
+
+func (x ErrorReason) String() string {
+	return protoimpl.X.EnumStringOf(x.Descriptor(), protoreflect.EnumNumber(x))
+}
+
+func (ErrorReason) Descriptor() protoreflect.EnumDescriptor {
+	return file_error_reason_proto_enumTypes[0].Descriptor()
+}
+
+func (ErrorReason) Type() protoreflect.EnumType {
+	return &file_error_reason_proto_enumTypes[0]
+}
+
+func (x ErrorReason) Number() protoreflect.EnumNumber {
+	return protoreflect.EnumNumber(x)
+}
+
+// Deprecated: Use ErrorReason.Descriptor instead.
+func (ErrorReason) EnumDescriptor() ([]byte, []int) {
+	return file_error_reason_proto_rawDescGZIP(), []int{0}
+}
+
+var File_error_reason_proto protoreflect.FileDescriptor
+
+var file_error_reason_proto_rawDesc = []byte{
+	0x0a, 0x12, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x5f, 0x72, 0x65, 0x61, 0x73, 0x6f, 0x6e, 0x2e, 0x70,
+	0x72, 0x6f, 0x74, 0x6f, 0x12, 0x06, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x1a, 0x0c, 0x65, 0x72,
+	0x72, 0x6f, 0x72, 0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x2a, 0x48, 0x0a, 0x0b, 0x45, 0x72,
+	0x72, 0x6f, 0x72, 0x52, 0x65, 0x61, 0x73, 0x6f, 0x6e, 0x12, 0x18, 0x0a, 0x0e, 0x55, 0x53, 0x45,
+	0x52, 0x5f, 0x4e, 0x4f, 0x54, 0x5f, 0x46, 0x4f, 0x55, 0x4e, 0x44, 0x10, 0x00, 0x1a, 0x04, 0xa8,
+	0x45, 0x94, 0x03, 0x12, 0x19, 0x0a, 0x0f, 0x43, 0x4f, 0x4e, 0x54, 0x45, 0x4e, 0x54, 0x5f, 0x4d,
+	0x49, 0x53, 0x53, 0x49, 0x4e, 0x47, 0x10, 0x01, 0x1a, 0x04, 0xa8, 0x45, 0x90, 0x03, 0x1a, 0x04,
+	0xa0, 0x45, 0xf4, 0x03, 0x42, 0x57, 0x0a, 0x0e, 0x62, 0x6c, 0x6f, 0x67, 0x2e, 0x76, 0x31, 0x2e,
+	0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x50, 0x01, 0x5a, 0x33, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62,
+	0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x67, 0x6f, 0x2d, 0x6b, 0x72, 0x61, 0x74, 0x6f, 0x73, 0x2f, 0x6b,
+	0x72, 0x61, 0x74, 0x6f, 0x73, 0x2f, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x73, 0x2f, 0x62,
+	0x6c, 0x6f, 0x67, 0x2f, 0x61, 0x70, 0x69, 0x2f, 0x76, 0x31, 0x3b, 0x76, 0x31, 0xa2, 0x02, 0x0d,
+	0x41, 0x50, 0x49, 0x42, 0x6c, 0x6f, 0x67, 0x45, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x62, 0x06, 0x70,
+	0x72, 0x6f, 0x74, 0x6f, 0x33,
+}
+
+var (
+	file_error_reason_proto_rawDescOnce sync.Once
+	file_error_reason_proto_rawDescData = file_error_reason_proto_rawDesc
+)
+
+func file_error_reason_proto_rawDescGZIP() []byte {
+	file_error_reason_proto_rawDescOnce.Do(func() {
+		file_error_reason_proto_rawDescData = protoimpl.X.CompressGZIP(file_error_reason_proto_rawDescData)
+	})
+	return file_error_reason_proto_rawDescData
+}
+
+var file_error_reason_proto_enumTypes = make([]protoimpl.EnumInfo, 1)
+var file_error_reason_proto_goTypes = []interface{}{
+	(ErrorReason)(0), // 0: errors.ErrorReason
+}
+var file_error_reason_proto_depIdxs = []int32{
+	0, // [0:0] is the sub-list for method output_type
+	0, // [0:0] is the sub-list for method input_type
+	0, // [0:0] is the sub-list for extension type_name
+	0, // [0:0] is the sub-list for extension extendee
+	0, // [0:0] is the sub-list for field type_name
+}
+
+func init() { file_error_reason_proto_init() }
+func file_error_reason_proto_init() {
+	if File_error_reason_proto != nil {
+		return
+	}
+	type x struct{}
+	out := protoimpl.TypeBuilder{
+		File: protoimpl.DescBuilder{
+			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
+			RawDescriptor: file_error_reason_proto_rawDesc,
+			NumEnums:      1,
+			NumMessages:   0,
+			NumExtensions: 0,
+			NumServices:   0,
+		},
+		GoTypes:           file_error_reason_proto_goTypes,
+		DependencyIndexes: file_error_reason_proto_depIdxs,
+		EnumInfos:         file_error_reason_proto_enumTypes,
+	}.Build()
+	File_error_reason_proto = out.File
+	file_error_reason_proto_rawDesc = nil
+	file_error_reason_proto_goTypes = nil
+	file_error_reason_proto_depIdxs = nil
+}

examples/errors/api/error_reason.proto

@@ -0,0 +1,17 @@
+syntax = "proto3";
+
+package errors;
+import "errors.proto";
+
+// 多语言特定包名，用于源代码引用
+option go_package = "github.com/go-kratos/kratos/examples/blog/api/v1;v1";
+option java_multiple_files = true;
+option java_package = "blog.v1.errors";
+option objc_class_prefix = "APIBlogErrors";
+
+enum ErrorReason {
+  option (errors.default_code) = 500;
+
+  USER_NOT_FOUND = 0 [(errors.code) = 404];
+  CONTENT_MISSING = 1 [(errors.code) = 400];;
+}

examples/errors/api/error_reason_errors.pb.go

@@ -0,0 +1,30 @@
+// Code generated by protoc-gen-go-errors. DO NOT EDIT.
+
+package api
+
+import (
+	fmt "fmt"
+	errors "github.com/go-kratos/kratos/v2/errors"
+)
+
+// This is a compile-time assertion to ensure that this generated file
+// is compatible with the kratos package it is being compiled against.
+const _ = errors.SupportPackageIsVersion1
+
+func IsUserNotFound(err error) bool {
+	e := errors.FromError(err)
+	return e.Reason == ErrorReason_USER_NOT_FOUND.String() && e.Code == 404
+}
+
+func ErrorUserNotFound(format string, args ...interface{}) *errors.Error {
+	return errors.New(404, ErrorReason_USER_NOT_FOUND.String(), fmt.Sprintf(format, args...))
+}
+
+func IsContentMissing(err error) bool {
+	e := errors.FromError(err)
+	return e.Reason == ErrorReason_CONTENT_MISSING.String() && e.Code == 400
+}
+
+func ErrorContentMissing(format string, args ...interface{}) *errors.Error {
+	return errors.New(400, ErrorReason_CONTENT_MISSING.String(), fmt.Sprintf(format, args...))
+}

examples/errors/api/errors.proto

@@ -0,0 +1,18 @@
+syntax = "proto3";
+
+package errors;
+
+option go_package = "github.com/go-kratos/kratos/v2/errors;v1";
+option java_multiple_files = true;
+option java_package = "com.github.kratos.errors";
+option objc_class_prefix = "KratosErrors";
+
+import "google/protobuf/descriptor.proto";
+
+extend google.protobuf.EnumOptions {
+  int32 default_code = 1108;
+}
+
+extend google.protobuf.EnumValueOptions {
+  int32 code = 1109;
+}

examples/errors/client/main.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"context"
+	"github.com/go-kratos/kratos/examples/errors/api"
+	"github.com/go-kratos/kratos/v2/errors"
+	"log"
+
+	pb "github.com/go-kratos/kratos/examples/helloworld/helloworld"
+	transgrpc "github.com/go-kratos/kratos/v2/transport/grpc"
+	transhttp "github.com/go-kratos/kratos/v2/transport/http"
+)
+
+func main() {
+	callHTTP()
+	callGRPC()
+}
+
+func callHTTP() {
+	conn, err := transhttp.NewClient(
+		context.Background(),
+		transhttp.WithEndpoint("127.0.0.1:8000"),
+	)
+	if err != nil {
+		panic(err)
+	}
+	client := pb.NewGreeterHTTPClient(conn)
+	reply, err := client.SayHello(context.Background(), &pb.HelloRequest{Name: "empty"})
+	if err != nil {
+		if errors.Code(err) == 500 {
+			log.Println(err)
+		}
+		if api.IsUserNotFound(err) {
+			log.Println("[http] USER_NOT_FOUND_ERROR", err)
+		}
+	} else {
+		log.Printf("[http] SayHello %s\n", reply.Message)
+	}
+}
+
+func callGRPC() {
+	conn, err := transgrpc.DialInsecure(
+		context.Background(),
+		transgrpc.WithEndpoint("127.0.0.1:9000"),
+	)
+	if err != nil {
+		panic(err)
+	}
+	client := pb.NewGreeterClient(conn)
+	reply, err := client.SayHello(context.Background(), &pb.HelloRequest{Name: "kratos"})
+	if err != nil {
+		e := errors.FromError(err)
+		if e.Reason == "USER_NAME_EMPTY" && e.Code == 500 {
+			log.Println("[grpc] USER_NAME_EMPTY", err)
+		}
+		if api.IsUserNotFound(err) {
+			log.Println("[grpc] USER_NOT_FOUND_ERROR", err)
+		}
+	} else {
+		log.Printf("[grpc] SayHello %+v\n", reply)
+	}
+}

examples/errors/server/main.go

@@ -0,0 +1,65 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"github.com/go-kratos/kratos/v2/errors"
+	"log"
+
+	"github.com/go-kratos/kratos/examples/errors/api"
+	"github.com/go-kratos/kratos/examples/helloworld/helloworld"
+	"github.com/go-kratos/kratos/v2"
+	"github.com/go-kratos/kratos/v2/transport/grpc"
+	"github.com/go-kratos/kratos/v2/transport/http"
+)
+
+// go build -ldflags "-X main.Version=x.y.z"
+var (
+	// Name is the name of the compiled software.
+	Name = "errors"
+	// Version is the version of the compiled software.
+	Version = "v1.0.0"
+)
+
+// server is used to implement helloworld.GreeterServer.
+type server struct {
+	helloworld.UnimplementedGreeterServer
+}
+
+// SayHello implements helloworld.GreeterServer
+func (s *server) SayHello(ctx context.Context, in *helloworld.HelloRequest) (*helloworld.HelloReply, error) {
+	fmt.Println(in.Name)
+	if in.Name == "empty" {
+		// Respond to errors through errors.New().
+		return nil, errors.New(500, "USER_NAME_EMPTY", "user name is empty")
+	}
+	if in.Name == "kratos" {
+		// Respond to errors with proto generated code.
+		return nil, api.ErrorUserNotFound("user %s not found", "kratos")
+	}
+	return &helloworld.HelloReply{Message: fmt.Sprintf("Hello %+v", in.Name)}, nil
+}
+
+func main() {
+	s := &server{}
+	grpcSrv := grpc.NewServer(
+		grpc.Address(":9000"),
+	)
+	httpSrv := http.NewServer(
+		http.Address(":8000"),
+	)
+	helloworld.RegisterGreeterServer(grpcSrv, s)
+	helloworld.RegisterGreeterHTTPServer(httpSrv, s)
+
+	app := kratos.New(
+		kratos.Name(Name),
+		kratos.Server(
+			httpSrv,
+			grpcSrv,
+		),
+	)
+
+	if err := app.Run(); err != nil {
+		log.Fatal(err)
+	}
+}