Repository: go-kratos/kratos
Pull request #1910 (2022-04-02 16:45:48)

feat: add error cause for statck trace
```go
if err := TODO(v); err != nil {
    return errors.BadRequest(reason, message).WithCause(cause)
}

if errors.Is(err, cause) {
    // TODO
}
if cause := new(MyError); errors.As(err, &cause) {
    // TODO
}
```

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> Merging [#1910](https://codecov.io/gh/go-kratos/kratos/pull/1910?src=pr&el=desc&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=go-kratos) (c51c2a8) into [main](https://codecov.io/gh/go-kratos/kratos/commit/558ef4ebaefe1bfab84553ae30064b39ea37abc0?el=desc&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=go-kratos) (558ef4e) will **decrease** coverage by `0.17%`.
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> :exclamation: Current head c51c2a8 differs from pull request most recent head 4ca2213. Consider uploading reports for the commit 4ca2213 to get more accurate results

```diff
@@            Coverage Diff             @@
##             main    #1910      +/-   ##
==========================================
- Coverage   80.85%   80.68%   -0.18%     
==========================================
  Files          80       80              
  Lines        3573     3588      +15     
==========================================
+ Hits         2889     2895       +6     
- Misses        477      485       +8     
- Partials      207      208       +1     
```


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|---|---|---|
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| [errors/errors.go](https://codecov.io/gh/go-kratos/kratos/pull/1910/diff?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=go-kratos#diff-ZXJyb3JzL2Vycm9ycy5nbw==) | `86.76% <66.66%> (-9.47%)` | :arrow_down: |
| [internal/context/context.go](https://codecov.io/gh/go-kratos/kratos/pull/1910/diff?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=go-kratos#diff-aW50ZXJuYWwvY29udGV4dC9jb250ZXh0Lmdv) | `97.01% <0.00%> (-2.99%)` | :arrow_down: |

------

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Patch:
diff --git a/README.md b/README.md
index c08a74c3..5c979c6b 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,7 @@
 
 ## About Kratos
   
-> The name is inspired by the game God of War which is based on Greek myths, tells the Kratos from mortals to become a God of War and launches the adventure of killing god.
+> The name is inspired by the game God of War which is based on Greek myths, tells the adventures of Kratos who became a god of war from a mortal and launched a god-killing slaughter.
 
 Kratos is a microservice-oriented governance framework implemented by golang, which offers convenient capabilities to help you quickly build a bulletproof application from scratch, such as:
 
diff --git a/README_zh.md b/README_zh.md
index b3ff21c3..63289acd 100644
--- a/README_zh.md
+++ b/README_zh.md
@@ -19,7 +19,7 @@ Translations: [English](README.md) | [简体中文](README_zh.md)
 
 Kratos 一套轻量级 Go 微服务框架，包含大量微服务相关功能及工具。  
 
-> 名字来源于:《战神》游戏以希腊神话为背景，讲述由凡人成为战神的奎托斯（Kratos）成为战神并展开弑神屠杀的冒险历程。
+> 名字来源于:《战神》游戏以希腊神话为背景，讲述奎托斯（Kratos）由凡人成为战神并展开弑神屠杀的冒险经历。
 
 ## Goals
 
diff --git a/cmd/protoc-gen-go-errors/errors.go b/cmd/protoc-gen-go-errors/errors.go
index db5e5195..a827c071 100644
--- a/cmd/protoc-gen-go-errors/errors.go
+++ b/cmd/protoc-gen-go-errors/errors.go
@@ -4,6 +4,9 @@ import (
 	"fmt"
 	"strings"
 
+	"golang.org/x/text/cases"
+	"golang.org/x/text/language"
+
 	"github.com/go-kratos/kratos/cmd/protoc-gen-go-errors/v2/errors"
 	"google.golang.org/protobuf/compiler/protogen"
 	"google.golang.org/protobuf/proto"
@@ -14,6 +17,8 @@ const (
 	fmtPackage    = protogen.GoImportPath("fmt")
 )
 
+var enCases = cases.Title(language.AmericanEnglish)
+
 // generateFile generates a _errors.pb.go file containing kratos errors definitions.
 func generateFile(gen *protogen.Plugin, file *protogen.File) *protogen.GeneratedFile {
 	if len(file.Enums) == 0 {
@@ -98,10 +103,10 @@ func case2Camel(name string) string {
 		if upperName == name {
 			name = strings.ToLower(name)
 		}
-		return strings.Title(name)
+		return enCases.String(name)
 	}
 	name = strings.ToLower(name)
 	name = strings.Replace(name, "_", " ", -1)
-	name = strings.Title(name)
+	name = enCases.String(name)
 	return strings.Replace(name, " ", "", -1)
 }
diff --git a/cmd/protoc-gen-go-errors/go.mod b/cmd/protoc-gen-go-errors/go.mod
index 423d91c8..4661ee6a 100644
--- a/cmd/protoc-gen-go-errors/go.mod
+++ b/cmd/protoc-gen-go-errors/go.mod
@@ -2,4 +2,7 @@ module github.com/go-kratos/kratos/cmd/protoc-gen-go-errors/v2
 
 go 1.16
 
-require google.golang.org/protobuf v1.27.1
+require (
+	golang.org/x/text v0.3.7 // indirect
+	google.golang.org/protobuf v1.27.1
+)
diff --git a/cmd/protoc-gen-go-errors/go.sum b/cmd/protoc-gen-go-errors/go.sum
index 03b1917b..5146f899 100644
--- a/cmd/protoc-gen-go-errors/go.sum
+++ b/cmd/protoc-gen-go-errors/go.sum
@@ -1,6 +1,9 @@
 github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
 github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543 h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=
 golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
diff --git a/cmd/protoc-gen-go-http/http.go b/cmd/protoc-gen-go-http/http.go
index a697968b..4886b806 100644
--- a/cmd/protoc-gen-go-http/http.go
+++ b/cmd/protoc-gen-go-http/http.go
@@ -8,7 +8,6 @@ import (
 
 	"google.golang.org/protobuf/reflect/protoreflect"
 
-	"github.com/go-kratos/kratos/v2"
 	"google.golang.org/genproto/googleapis/api/annotations"
 	"google.golang.org/protobuf/compiler/protogen"
 	"google.golang.org/protobuf/proto"
@@ -32,7 +31,7 @@ func generateFile(gen *protogen.Plugin, file *protogen.File, omitempty bool) *pr
 	g := gen.NewGeneratedFile(filename, file.GoImportPath)
 	g.P("// Code generated by protoc-gen-go-http. DO NOT EDIT.")
 	g.P("// versions:")
-	g.P(fmt.Sprintf("// protoc-gen-go-http %s", kratos.Release))
+	g.P(fmt.Sprintf("// protoc-gen-go-http %s", release))
 	g.P()
 	g.P("package ", file.GoPackageName)
 	g.P()
diff --git a/contrib/registry/consul/client.go b/contrib/registry/consul/client.go
index edbc6944..80ea383a 100644
--- a/contrib/registry/consul/client.go
+++ b/contrib/registry/consul/client.go
@@ -27,15 +27,18 @@ type Client struct {
 	healthcheckInterval int
 	// heartbeat enable heartbeat
 	heartbeat bool
+	// deregisterCriticalServiceAfter time interval in seconds
+	deregisterCriticalServiceAfter int
 }
 
 // NewClient creates consul client
 func NewClient(cli *api.Client) *Client {
 	c := &Client{
-		cli:                 cli,
-		resolver:            defaultResolver,
-		healthcheckInterval: 10,
-		heartbeat:           true,
+		cli:                            cli,
+		resolver:                       defaultResolver,
+		healthcheckInterval:            10,
+		heartbeat:                      true,
+		deregisterCriticalServiceAfter: 600,
 	}
 	c.ctx, c.cancel = context.WithCancel(context.Background())
 	return c
@@ -123,7 +126,7 @@ func (c *Client) Register(_ context.Context, svc *registry.ServiceInstance, enab
 			asr.Checks = append(asr.Checks, &api.AgentServiceCheck{
 				TCP:                            address,
 				Interval:                       fmt.Sprintf("%ds", c.healthcheckInterval),
-				DeregisterCriticalServiceAfter: fmt.Sprintf("%ds", c.healthcheckInterval*60),
+				DeregisterCriticalServiceAfter: fmt.Sprintf("%ds", c.deregisterCriticalServiceAfter),
 				Timeout:                        "5s",
 			})
 		}
@@ -132,7 +135,7 @@ func (c *Client) Register(_ context.Context, svc *registry.ServiceInstance, enab
 		asr.Checks = append(asr.Checks, &api.AgentServiceCheck{
 			CheckID:                        "service:" + svc.ID,
 			TTL:                            fmt.Sprintf("%ds", c.healthcheckInterval*2),
-			DeregisterCriticalServiceAfter: fmt.Sprintf("%ds", c.healthcheckInterval*60),
+			DeregisterCriticalServiceAfter: fmt.Sprintf("%ds", c.deregisterCriticalServiceAfter),
 		})
 	}
 
diff --git a/contrib/registry/consul/registry.go b/contrib/registry/consul/registry.go
index c3bc2546..7e454ea2 100644
--- a/contrib/registry/consul/registry.go
+++ b/contrib/registry/consul/registry.go
@@ -54,6 +54,15 @@ func WithHealthCheckInterval(interval int) Option {
 	}
 }
 
+// WithDeregisterCriticalServiceAfter with deregister-critical-service-after in seconds.
+func WithDeregisterCriticalServiceAfter(interval int) Option {
+	return func(o *Registry) {
+		if o.cli != nil {
+			o.cli.deregisterCriticalServiceAfter = interval
+		}
+	}
+}
+
 // Config is consul registry config
 type Config struct {
 	*api.Config
diff --git a/errors/errors.go b/errors/errors.go
index c9f6ef00..f3031616 100644
--- a/errors/errors.go
+++ b/errors/errors.go
@@ -7,9 +7,10 @@ import (
 	httpstatus "github.com/go-kratos/kratos/v2/transport/http/status"
 	"google.golang.org/genproto/googleapis/rpc/errdetails"
 	"google.golang.org/grpc/status"
-	"google.golang.org/protobuf/proto"
 )
 
+//go:generate protoc -I. --go_out=paths=source_relative:. errors.proto
+
 const (
 	// UnknownCode is unknown code for error info.
 	UnknownCode = 500
@@ -19,21 +20,18 @@ const (
 	SupportPackageIsVersion1 = true
 )
 
-//go:generate protoc -I. --go_out=paths=source_relative:. errors.proto
+// Error is a status error.
+type Error struct {
+	Status
+	cause error
+}
 
 func (e *Error) Error() string {
-	return fmt.Sprintf("error: code = %d reason = %s message = %s metadata = %v", e.Code, e.Reason, e.Message, e.Metadata)
+	return fmt.Sprintf("error: code = %d reason = %s message = %s metadata = %v cause = %v", e.Code, e.Reason, e.Message, e.Metadata, e.cause)
 }
 
-// GRPCStatus returns the Status represented by se.
-func (e *Error) GRPCStatus() *status.Status {
-	s, _ := status.New(httpstatus.ToGRPCCode(int(e.Code)), e.Message).
-		WithDetails(&errdetails.ErrorInfo{
-			Reason:   e.Reason,
-			Metadata: e.Metadata,
-		})
-	return s
-}
+// Unwrap provides compatibility for Go 1.13 error chains.
+func (e *Error) Unwrap() error { return e.cause }
 
 // Is matches each error in the chain with the target value.
 func (e *Error) Is(err error) bool {
@@ -43,19 +41,38 @@ func (e *Error) Is(err error) bool {
 	return false
 }
 
+// WithCause with the underlying cause of the error.
+func (e *Error) WithCause(cause error) *Error {
+	err := Clone(e)
+	err.cause = cause
+	return err
+}
+
 // WithMetadata with an MD formed by the mapping of key, value.
 func (e *Error) WithMetadata(md map[string]string) *Error {
-	err := proto.Clone(e).(*Error)
+	err := Clone(e)
 	err.Metadata = md
 	return err
 }
 
+// GRPCStatus returns the Status represented by se.
+func (e *Error) GRPCStatus() *status.Status {
+	s, _ := status.New(httpstatus.ToGRPCCode(int(e.Code)), e.Message).
+		WithDetails(&errdetails.ErrorInfo{
+			Reason:   e.Reason,
+			Metadata: e.Metadata,
+		})
+	return s
+}
+
 // New returns an error object for the code, message.
 func New(code int, reason, message string) *Error {
 	return &Error{
-		Code:    int32(code),
-		Message: message,
-		Reason:  reason,
+		Status: Status{
+			Code:    int32(code),
+			Message: message,
+			Reason:  reason,
+		},
 	}
 }
 
@@ -87,6 +104,23 @@ func Reason(err error) string {
 	return FromError(err).Reason
 }
 
+// Clone deep clone error to a new error.
+func Clone(err *Error) *Error {
+	metadata := make(map[string]string, len(err.Metadata))
+	for k, v := range err.Metadata {
+		metadata[k] = v
+	}
+	return &Error{
+		cause: err.cause,
+		Status: Status{
+			Code:     err.Code,
+			Reason:   err.Reason,
+			Message:  err.Message,
+			Metadata: metadata,
+		},
+	}
+}
+
 // FromError try to convert an error to *Error.
 // It supports wrapped errors.
 func FromError(err error) *Error {
diff --git a/errors/errors.pb.go b/errors/errors.pb.go
index d09b70fa..0f4e28f2 100644
--- a/errors/errors.pb.go
+++ b/errors/errors.pb.go
@@ -1,8 +1,8 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
 // 	protoc-gen-go v1.27.1
-// 	protoc        v3.17.3
-// source: errors/errors.proto
+// 	protoc        v3.19.4
+// source: errors.proto
 
 package errors
 
@@ -21,7 +21,7 @@ const (
 	_ = protoimpl.EnforceVersion(protoimpl.MaxVersion - 20)
 )
 
-type Error struct {
+type Status struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
 	unknownFields protoimpl.UnknownFields
@@ -32,23 +32,23 @@ type Error struct {
 	Metadata map[string]string `protobuf:"bytes,4,rep,name=metadata,proto3" json:"metadata,omitempty" protobuf_key:"bytes,1,opt,name=key,proto3" protobuf_val:"bytes,2,opt,name=value,proto3"`
 }
 
-func (x *Error) Reset() {
-	*x = Error{}
+func (x *Status) Reset() {
+	*x = Status{}
 	if protoimpl.UnsafeEnabled {
-		mi := &file_errors_errors_proto_msgTypes[0]
+		mi := &file_errors_proto_msgTypes[0]
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		ms.StoreMessageInfo(mi)
 	}
 }
 
-func (x *Error) String() string {
+func (x *Status) String() string {
 	return protoimpl.X.MessageStringOf(x)
 }
 
-func (*Error) ProtoMessage() {}
+func (*Status) ProtoMessage() {}
 
-func (x *Error) ProtoReflect() protoreflect.Message {
-	mi := &file_errors_errors_proto_msgTypes[0]
+func (x *Status) ProtoReflect() protoreflect.Message {
+	mi := &file_errors_proto_msgTypes[0]
 	if protoimpl.UnsafeEnabled && x != nil {
 		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
 		if ms.LoadMessageInfo() == nil {
@@ -59,47 +59,47 @@ func (x *Error) ProtoReflect() protoreflect.Message {
 	return mi.MessageOf(x)
 }
 
-// Deprecated: Use Error.ProtoReflect.Descriptor instead.
-func (*Error) Descriptor() ([]byte, []int) {
-	return file_errors_errors_proto_rawDescGZIP(), []int{0}
+// Deprecated: Use Status.ProtoReflect.Descriptor instead.
+func (*Status) Descriptor() ([]byte, []int) {
+	return file_errors_proto_rawDescGZIP(), []int{0}
 }
 
-func (x *Error) GetCode() int32 {
+func (x *Status) GetCode() int32 {
 	if x != nil {
 		return x.Code
 	}
 	return 0
 }
 
-func (x *Error) GetReason() string {
+func (x *Status) GetReason() string {
 	if x != nil {
 		return x.Reason
 	}
 	return ""
 }
 
-func (x *Error) GetMessage() string {
+func (x *Status) GetMessage() string {
 	if x != nil {
 		return x.Message
 	}
 	return ""
 }
 
-func (x *Error) GetMetadata() map[string]string {
+func (x *Status) GetMetadata() map[string]string {
 	if x != nil {
 		return x.Metadata
 	}
 	return nil
 }
 
-var file_errors_errors_proto_extTypes = []protoimpl.ExtensionInfo{
+var file_errors_proto_extTypes = []protoimpl.ExtensionInfo{
 	{
 		ExtendedType:  (*descriptorpb.EnumOptions)(nil),
 		ExtensionType: (*int32)(nil),
 		Field:         1108,
 		Name:          "errors.default_code",
 		Tag:           "varint,1108,opt,name=default_code",
-		Filename:      "errors/errors.proto",
+		Filename:      "errors.proto",
 	},
 	{
 		ExtendedType:  (*descriptorpb.EnumValueOptions)(nil),
@@ -107,79 +107,78 @@ var file_errors_errors_proto_extTypes = []protoimpl.ExtensionInfo{
 		Field:         1109,
 		Name:          "errors.code",
 		Tag:           "varint,1109,opt,name=code",
-		Filename:      "errors/errors.proto",
+		Filename:      "errors.proto",
 	},
 }
 
 // Extension fields to descriptorpb.EnumOptions.
 var (
 	// optional int32 default_code = 1108;
-	E_DefaultCode = &file_errors_errors_proto_extTypes[0]
+	E_DefaultCode = &file_errors_proto_extTypes[0]
 )
 
 // Extension fields to descriptorpb.EnumValueOptions.
 var (
 	// optional int32 code = 1109;
-	E_Code = &file_errors_errors_proto_extTypes[1]
+	E_Code = &file_errors_proto_extTypes[1]
 )
 
-var File_errors_errors_proto protoreflect.FileDescriptor
-
-var file_errors_errors_proto_rawDesc = []byte{
-	0x0a, 0x13, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x2f, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x2e,
-	0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x06, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x1a, 0x20, 0x67,
-	0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2f, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2f, 0x64,
-	0x65, 0x73, 0x63, 0x72, 0x69, 0x70, 0x74, 0x6f, 0x72, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x22,
-	0xc3, 0x01, 0x0a, 0x05, 0x45, 0x72, 0x72, 0x6f, 0x72, 0x12, 0x12, 0x0a, 0x04, 0x63, 0x6f, 0x64,
-	0x65, 0x18, 0x01, 0x20, 0x01, 0x28, 0x05, 0x52, 0x04, 0x63, 0x6f, 0x64, 0x65, 0x12, 0x16, 0x0a,
-	0x06, 0x72, 0x65, 0x61, 0x73, 0x6f, 0x6e, 0x18, 0x02, 0x20, 0x01, 0x28, 0x09, 0x52, 0x06, 0x72,
-	0x65, 0x61, 0x73, 0x6f, 0x6e, 0x12, 0x18, 0x0a, 0x07, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65,
-	0x18, 0x03, 0x20, 0x01, 0x28, 0x09, 0x52, 0x07, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x12,
-	0x37, 0x0a, 0x08, 0x6d, 0x65, 0x74, 0x61, 0x64, 0x61, 0x74, 0x61, 0x18, 0x04, 0x20, 0x03, 0x28,
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-	0x6f, 0x6e, 0x73, 0x18, 0xd4, 0x08, 0x20, 0x01, 0x28, 0x05, 0x52, 0x0b, 0x64, 0x65, 0x66, 0x61,
-	0x75, 0x6c, 0x74, 0x43, 0x6f, 0x64, 0x65, 0x3a, 0x36, 0x0a, 0x04, 0x63, 0x6f, 0x64, 0x65, 0x12,
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-	0x59, 0x0a, 0x18, 0x63, 0x6f, 0x6d, 0x2e, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x6b, 0x72,
-	0x61, 0x74, 0x6f, 0x73, 0x2e, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x50, 0x01, 0x5a, 0x2c, 0x67,
-	0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x63, 0x6f, 0x6d, 0x2f, 0x67, 0x6f, 0x2d, 0x6b, 0x72, 0x61,
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-	0x6f, 0x33,
+var File_errors_proto protoreflect.FileDescriptor
+
+var file_errors_proto_rawDesc = []byte{
+	0x0a, 0x0c, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x12, 0x06,
+	0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x1a, 0x20, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2f, 0x70,
+	0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2f, 0x64, 0x65, 0x73, 0x63, 0x72, 0x69, 0x70, 0x74,
+	0x6f, 0x72, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x22, 0xc5, 0x01, 0x0a, 0x06, 0x53, 0x74, 0x61,
+	0x74, 0x75, 0x73, 0x12, 0x12, 0x0a, 0x04, 0x63, 0x6f, 0x64, 0x65, 0x18, 0x01, 0x20, 0x01, 0x28,
+	0x05, 0x52, 0x04, 0x63, 0x6f, 0x64, 0x65, 0x12, 0x16, 0x0a, 0x06, 0x72, 0x65, 0x61, 0x73, 0x6f,
+	0x6e, 0x18, 0x02, 0x20, 0x01, 0x28, 0x09, 0x52, 0x06, 0x72, 0x65, 0x61, 0x73, 0x6f, 0x6e, 0x12,
+	0x18, 0x0a, 0x07, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x18, 0x03, 0x20, 0x01, 0x28, 0x09,
+	0x52, 0x07, 0x6d, 0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x12, 0x38, 0x0a, 0x08, 0x6d, 0x65, 0x74,
+	0x61, 0x64, 0x61, 0x74, 0x61, 0x18, 0x04, 0x20, 0x03, 0x28, 0x0b, 0x32, 0x1c, 0x2e, 0x65, 0x72,
+	0x72, 0x6f, 0x72, 0x73, 0x2e, 0x53, 0x74, 0x61, 0x74, 0x75, 0x73, 0x2e, 0x4d, 0x65, 0x74, 0x61,
+	0x64, 0x61, 0x74, 0x61, 0x45, 0x6e, 0x74, 0x72, 0x79, 0x52, 0x08, 0x6d, 0x65, 0x74, 0x61, 0x64,
+	0x61, 0x74, 0x61, 0x1a, 0x3b, 0x0a, 0x0d, 0x4d, 0x65, 0x74, 0x61, 0x64, 0x61, 0x74, 0x61, 0x45,
+	0x6e, 0x74, 0x72, 0x79, 0x12, 0x10, 0x0a, 0x03, 0x6b, 0x65, 0x79, 0x18, 0x01, 0x20, 0x01, 0x28,
+	0x09, 0x52, 0x03, 0x6b, 0x65, 0x79, 0x12, 0x14, 0x0a, 0x05, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x18,
+	0x02, 0x20, 0x01, 0x28, 0x09, 0x52, 0x05, 0x76, 0x61, 0x6c, 0x75, 0x65, 0x3a, 0x02, 0x38, 0x01,
+	0x3a, 0x40, 0x0a, 0x0c, 0x64, 0x65, 0x66, 0x61, 0x75, 0x6c, 0x74, 0x5f, 0x63, 0x6f, 0x64, 0x65,
+	0x12, 0x1c, 0x2e, 0x67, 0x6f, 0x6f, 0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62,
+	0x75, 0x66, 0x2e, 0x45, 0x6e, 0x75, 0x6d, 0x4f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x73, 0x18, 0xd4,
+	0x08, 0x20, 0x01, 0x28, 0x05, 0x52, 0x0b, 0x64, 0x65, 0x66, 0x61, 0x75, 0x6c, 0x74, 0x43, 0x6f,
+	0x64, 0x65, 0x3a, 0x36, 0x0a, 0x04, 0x63, 0x6f, 0x64, 0x65, 0x12, 0x21, 0x2e, 0x67, 0x6f, 0x6f,
+	0x67, 0x6c, 0x65, 0x2e, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x62, 0x75, 0x66, 0x2e, 0x45, 0x6e, 0x75,
+	0x6d, 0x56, 0x61, 0x6c, 0x75, 0x65, 0x4f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x73, 0x18, 0xd5, 0x08,
+	0x20, 0x01, 0x28, 0x05, 0x52, 0x04, 0x63, 0x6f, 0x64, 0x65, 0x42, 0x59, 0x0a, 0x18, 0x63, 0x6f,
+	0x6d, 0x2e, 0x67, 0x69, 0x74, 0x68, 0x75, 0x62, 0x2e, 0x6b, 0x72, 0x61, 0x74, 0x6f, 0x73, 0x2e,
+	0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x50, 0x01, 0x5a, 0x2c, 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, 0x76, 0x32, 0x2f, 0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0x3b,
+	0x65, 0x72, 0x72, 0x6f, 0x72, 0x73, 0xa2, 0x02, 0x0c, 0x4b, 0x72, 0x61, 0x74, 0x6f, 0x73, 0x45,
+	0x72, 0x72, 0x6f, 0x72, 0x73, 0x62, 0x06, 0x70, 0x72, 0x6f, 0x74, 0x6f, 0x33,
 }
 
 var (
-	file_errors_errors_proto_rawDescOnce sync.Once
-	file_errors_errors_proto_rawDescData = file_errors_errors_proto_rawDesc
+	file_errors_proto_rawDescOnce sync.Once
+	file_errors_proto_rawDescData = file_errors_proto_rawDesc
 )
 
-func file_errors_errors_proto_rawDescGZIP() []byte {
-	file_errors_errors_proto_rawDescOnce.Do(func() {
-		file_errors_errors_proto_rawDescData = protoimpl.X.CompressGZIP(file_errors_errors_proto_rawDescData)
+func file_errors_proto_rawDescGZIP() []byte {
+	file_errors_proto_rawDescOnce.Do(func() {
+		file_errors_proto_rawDescData = protoimpl.X.CompressGZIP(file_errors_proto_rawDescData)
 	})
-	return file_errors_errors_proto_rawDescData
+	return file_errors_proto_rawDescData
 }
 
-var file_errors_errors_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
-var file_errors_errors_proto_goTypes = []interface{}{
-	(*Error)(nil),                         // 0: errors.Error
-	nil,                                   // 1: errors.Error.MetadataEntry
+var file_errors_proto_msgTypes = make([]protoimpl.MessageInfo, 2)
+var file_errors_proto_goTypes = []interface{}{
+	(*Status)(nil),                        // 0: errors.Status
+	nil,                                   // 1: errors.Status.MetadataEntry
 	(*descriptorpb.EnumOptions)(nil),      // 2: google.protobuf.EnumOptions
 	(*descriptorpb.EnumValueOptions)(nil), // 3: google.protobuf.EnumValueOptions
 }
-var file_errors_errors_proto_depIdxs = []int32{
-	1, // 0: errors.Error.metadata:type_name -> errors.Error.MetadataEntry
+var file_errors_proto_depIdxs = []int32{
+	1, // 0: errors.Status.metadata:type_name -> errors.Status.MetadataEntry
 	2, // 1: errors.default_code:extendee -> google.protobuf.EnumOptions
 	3, // 2: errors.code:extendee -> google.protobuf.EnumValueOptions
 	3, // [3:3] is the sub-list for method output_type
@@ -189,14 +188,14 @@ var file_errors_errors_proto_depIdxs = []int32{
 	0, // [0:1] is the sub-list for field type_name
 }
 
-func init() { file_errors_errors_proto_init() }
-func file_errors_errors_proto_init() {
-	if File_errors_errors_proto != nil {
+func init() { file_errors_proto_init() }
+func file_errors_proto_init() {
+	if File_errors_proto != nil {
 		return
 	}
 	if !protoimpl.UnsafeEnabled {
-		file_errors_errors_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
-			switch v := v.(*Error); i {
+		file_errors_proto_msgTypes[0].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*Status); i {
 			case 0:
 				return &v.state
 			case 1:
@@ -212,19 +211,19 @@ func file_errors_errors_proto_init() {
 	out := protoimpl.TypeBuilder{
 		File: protoimpl.DescBuilder{
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
-			RawDescriptor: file_errors_errors_proto_rawDesc,
+			RawDescriptor: file_errors_proto_rawDesc,
 			NumEnums:      0,
 			NumMessages:   2,
 			NumExtensions: 2,
 			NumServices:   0,
 		},
-		GoTypes:           file_errors_errors_proto_goTypes,
-		DependencyIndexes: file_errors_errors_proto_depIdxs,
-		MessageInfos:      file_errors_errors_proto_msgTypes,
-		ExtensionInfos:    file_errors_errors_proto_extTypes,
+		GoTypes:           file_errors_proto_goTypes,
+		DependencyIndexes: file_errors_proto_depIdxs,
+		MessageInfos:      file_errors_proto_msgTypes,
+		ExtensionInfos:    file_errors_proto_extTypes,
 	}.Build()
-	File_errors_errors_proto = out.File
-	file_errors_errors_proto_rawDesc = nil
-	file_errors_errors_proto_goTypes = nil
-	file_errors_errors_proto_depIdxs = nil
+	File_errors_proto = out.File
+	file_errors_proto_rawDesc = nil
+	file_errors_proto_goTypes = nil
+	file_errors_proto_depIdxs = nil
 }
diff --git a/errors/errors.proto b/errors/errors.proto
index ff6766b4..ab14f20b 100644
--- a/errors/errors.proto
+++ b/errors/errors.proto
@@ -9,7 +9,7 @@ option objc_class_prefix = "KratosErrors";
 
 import "google/protobuf/descriptor.proto";
 
-message Error {
+message Status {
   int32 code = 1;
   string reason = 2;
   string message = 3;
diff --git a/middleware/validate/validate.go b/middleware/validate/validate.go
index a6eee1f0..f33d76e4 100644
--- a/middleware/validate/validate.go
+++ b/middleware/validate/validate.go
@@ -17,7 +17,7 @@ func Validator() middleware.Middleware {
 		return func(ctx context.Context, req interface{}) (reply interface{}, err error) {
 			if v, ok := req.(validator); ok {
 				if err := v.Validate(); err != nil {
-					return nil, errors.BadRequest("VALIDATOR", err.Error())
+					return nil, errors.BadRequest("VALIDATOR", err.Error()).WithCause(err)
 				}
 			}
 			return handler(ctx, req)
diff --git a/transport/grpc/codec.go b/transport/grpc/codec.go
new file mode 100644
index 00000000..1b2c8289
--- /dev/null
+++ b/transport/grpc/codec.go
@@ -0,0 +1,36 @@
+package grpc
+
+import (
+	"fmt"
+
+	"github.com/go-kratos/kratos/v2/encoding/json"
+	"google.golang.org/grpc/encoding"
+	"google.golang.org/protobuf/proto"
+)
+
+func init() {
+	encoding.RegisterCodec(codec{})
+}
+
+// codec is a Codec implementation with protobuf. It is the default codec for gRPC.
+type codec struct{}
+
+func (codec) Marshal(v interface{}) ([]byte, error) {
+	vv, ok := v.(proto.Message)
+	if !ok {
+		return nil, fmt.Errorf("failed to marshal, message is %T, want proto.Message", v)
+	}
+	return json.MarshalOptions.Marshal(vv)
+}
+
+func (codec) Unmarshal(data []byte, v interface{}) error {
+	vv, ok := v.(proto.Message)
+	if !ok {
+		return fmt.Errorf("failed to unmarshal, message is %T, want proto.Message", v)
+	}
+	return json.UnmarshalOptions.Unmarshal(data, vv)
+}
+
+func (codec) Name() string {
+	return "json"
+}
diff --git a/transport/http/client.go b/transport/http/client.go
index 17cd34e3..55719eb9 100644
--- a/transport/http/client.go
+++ b/transport/http/client.go
@@ -341,7 +341,7 @@ func DefaultErrorDecoder(ctx context.Context, res *http.Response) error {
 			return e
 		}
 	}
-	return errors.Errorf(res.StatusCode, errors.UnknownReason, err.Error())
+	return errors.Newf(res.StatusCode, errors.UnknownReason, "").WithCause(err)
 }
 
 // CodecForResponse get encoding.Codec via http.Response
diff --git a/transport/http/status/status.go b/transport/http/status/status.go
index d2240ec7..2f6a717f 100644
--- a/transport/http/status/status.go
+++ b/transport/http/status/status.go
@@ -13,6 +13,7 @@ const (
 	ClientClosed = 499
 )
 
+// Converter is a status converter.
 type Converter interface {
 	// ToGRPCCode converts an HTTP error code into the corresponding gRPC response status.
 	ToGRPCCode(code int) codes.Code
@@ -23,6 +24,7 @@ type Converter interface {
 
 type statusConverter struct{}
 
+// DefaultConverter default converter.
 var DefaultConverter Converter = statusConverter{}
 
 // ToGRPCCode converts a HTTP error code into the corresponding gRPC response status.


Test patch:
diff --git a/errors/errors_test.go b/errors/errors_test.go
index 01217bdc..f76d5151 100644
--- a/errors/errors_test.go
+++ b/errors/errors_test.go
@@ -12,7 +12,11 @@ import (
 	"google.golang.org/grpc/test/grpc_testing"
 )
 
-func TestError(t *testing.T) {
+type TestError struct{ message string }
+
+func (e *TestError) Error() string { return e.message }
+
+func TestErrors(t *testing.T) {
 	var base *Error
 	err := Newf(http.StatusBadRequest, "reason", "message")
 	err2 := Newf(http.StatusBadRequest, "reason", "message")
@@ -76,13 +80,13 @@ func TestIs(t *testing.T) {
 	}{
 		{
 			name: "true",
-			e:    &Error{Code: 404, Reason: "test"},
+			e:    New(404, "test", ""),
 			err:  New(http.StatusNotFound, "test", ""),
 			want: true,
 		},
 		{
 			name: "false",
-			e:    &Error{Reason: "test"},
+			e:    New(0, "test", ""),
 			err:  errors.New("test"),
 			want: false,
 		},
@@ -96,6 +100,19 @@ func TestIs(t *testing.T) {
 	}
 }
 
+func TestCause(t *testing.T) {
+	testError := &TestError{message: "test"}
+	err := BadRequest("foo", "bar").WithCause(testError)
+	if !errors.Is(err, testError) {
+		t.Fatalf("want %v but got %v", testError, err)
+	}
+	if te := new(TestError); errors.As(err, &te) {
+		if te.message != testError.message {
+			t.Fatalf("want %s but got %s", testError.message, te.message)
+		}
+	}
+}
+
 func TestOther(t *testing.T) {
 	if !reflect.DeepEqual(Code(nil), 200) {
 		t.Errorf("Code(nil) = %v, want %v", Code(nil), 200)
diff --git a/selector/node/direct/direct_test.go b/selector/node/direct/direct_test.go
index 063307da..d498c55c 100644
--- a/selector/node/direct/direct_test.go
+++ b/selector/node/direct/direct_test.go
@@ -31,11 +31,11 @@ func TestDirect(t *testing.T) {
 	if !reflect.DeepEqual(float64(10), wn.Weight()) {
 		t.Errorf("expect %v, got %v", float64(10), wn.Weight())
 	}
-	if time.Millisecond*15 <= wn.PickElapsed() {
-		t.Errorf("time.Millisecond*15 <= wn.PickElapsed()(%s)", wn.PickElapsed())
+	if time.Millisecond*20 <= wn.PickElapsed() {
+		t.Errorf("20ms <= wn.PickElapsed()(%s)", wn.PickElapsed())
 	}
-	if time.Millisecond*5 >= wn.PickElapsed() {
-		t.Errorf("time.Millisecond*5 >= wn.PickElapsed()(%s)", wn.PickElapsed())
+	if time.Millisecond*10 >= wn.PickElapsed() {
+		t.Errorf("10ms >= wn.PickElapsed()(%s)", wn.PickElapsed())
 	}
 }
 
diff --git a/transport/http/client_test.go b/transport/http/client_test.go
index 61365223..731d111d 100644
--- a/transport/http/client_test.go
+++ b/transport/http/client_test.go
@@ -255,14 +255,14 @@ func TestDefaultErrorDecoder(t *testing.T) {
 	if err2 == nil {
 		t.Errorf("expected error, got nil")
 	}
-	if !reflect.DeepEqual(int32(500), err2.(*kratosErrors.Error).GetCode()) {
-		t.Errorf("expected %v, got %v", 500, err2.(*kratosErrors.Error).GetCode())
+	if !reflect.DeepEqual(int32(500), err2.(*kratosErrors.Error).Code) {
+		t.Errorf("expected %v, got %v", 500, err2.(*kratosErrors.Error).Code)
 	}
-	if !reflect.DeepEqual("hi", err2.(*kratosErrors.Error).GetMessage()) {
-		t.Errorf("expected %v, got %v", "hi", err2.(*kratosErrors.Error).GetMessage())
+	if !reflect.DeepEqual("hi", err2.(*kratosErrors.Error).Message) {
+		t.Errorf("expected %v, got %v", "hi", err2.(*kratosErrors.Error).Message)
 	}
-	if !reflect.DeepEqual("FOO", err2.(*kratosErrors.Error).GetReason()) {
-		t.Errorf("expected %v, got %v", "FOO", err2.(*kratosErrors.Error).GetReason())
+	if !reflect.DeepEqual("FOO", err2.(*kratosErrors.Error).Reason) {
+		t.Errorf("expected %v, got %v", "FOO", err2.(*kratosErrors.Error).Reason)
 	}
 }
 
diff --git a/transport/http/codec_test.go b/transport/http/codec_test.go
index 88089072..ad77eeb6 100644
--- a/transport/http/codec_test.go
+++ b/transport/http/codec_test.go
@@ -87,7 +87,7 @@ func TestDefaultResponseEncoderWithError(t *testing.T) {
 	}
 	req.Header.Set("Content-Type", "application/json")
 
-	se := &errors.Error{Code: 511}
+	se := errors.New(511, "", "")
 	DefaultErrorEncoder(w, req, se)
 	if !reflect.DeepEqual("application/json", w.Header().Get("Content-Type")) {
 		t.Errorf("expected %v, got %v", "application/json", w.Header().Get("Content-Type"))
diff --git a/transport/http/server_test.go b/transport/http/server_test.go
index 8fdaf3cc..34f2b855 100644
--- a/transport/http/server_test.go
+++ b/transport/http/server_test.go
@@ -36,6 +36,11 @@ func TestServer(t *testing.T) {
 	srv.HandleHeader("content-type", "application/grpc-web+json", func(w http.ResponseWriter, r *http.Request) {
 		_ = json.NewEncoder(w).Encode(testData{Path: r.RequestURI})
 	})
+	srv.Route("/errors").GET("/cause", func(ctx Context) error {
+		return errors.BadRequest("xxx", "zzz").
+			WithMetadata(map[string]string{"foo": "bar"}).
+			WithCause(fmt.Errorf("error cause"))
+	})
 
 	if e, err := srv.Endpoint(); err != nil || e == nil || strings.HasSuffix(e.Host, ":0") {
 		t.Fatal(e, err)
@@ -49,11 +54,45 @@ func TestServer(t *testing.T) {
 	time.Sleep(time.Second)
 	testHeader(t, srv)
 	testClient(t, srv)
+	testAccept(t, srv)
 	if srv.Stop(ctx) != nil {
 		t.Errorf("expected nil got %v", srv.Stop(ctx))
 	}
 }
 
+func testAccept(t *testing.T, srv *Server) {
+	tests := []struct {
+		method      string
+		path        string
+		contentType string
+	}{
+		{"GET", "/errors/cause", "application/json"},
+		{"GET", "/errors/cause", "application/proto"},
+	}
+	e, err := srv.Endpoint()
+	if err != nil {
+		t.Errorf("expected nil got %v", err)
+	}
+	client, err := NewClient(context.Background(), WithEndpoint(e.Host))
+	if err != nil {
+		t.Errorf("expected nil got %v", err)
+	}
+	for _, test := range tests {
+		req, err := http.NewRequest(test.method, e.String()+test.path, nil)
+		if err != nil {
+			t.Errorf("expected nil got %v", err)
+		}
+		req.Header.Set("Content-Type", test.contentType)
+		resp, err := client.Do(req)
+		if errors.Code(err) != 400 {
+			t.Errorf("expected 400 got %v", err)
+		}
+		if err == nil {
+			resp.Body.Close()
+		}
+	}
+}
+
 func testHeader(t *testing.T, srv *Server) {
 	e, err := srv.Endpoint()
 	if err != nil {
@@ -80,20 +119,22 @@ func testClient(t *testing.T, srv *Server) {
 	tests := []struct {
 		method string
 		path   string
+		code   int
 	}{
-		{"GET", "/index"},
-		{"PUT", "/index"},
-		{"POST", "/index"},
-		{"PATCH", "/index"},
-		{"DELETE", "/index"},
+		{"GET", "/index", 200},
+		{"PUT", "/index", 200},
+		{"POST", "/index", 200},
+		{"PATCH", "/index", 200},
+		{"DELETE", "/index", 200},
 
-		{"GET", "/index/1"},
-		{"PUT", "/index/1"},
-		{"POST", "/index/1"},
-		{"PATCH", "/index/1"},
-		{"DELETE", "/index/1"},
+		{"GET", "/index/1", 200},
+		{"PUT", "/index/1", 200},
+		{"POST", "/index/1", 200},
+		{"PATCH", "/index/1", 200},
+		{"DELETE", "/index/1", 200},
 
-		{"GET", "/index/notfound"},
+		{"GET", "/index/notfound", 404},
+		{"GET", "/errors/cause", 400},
 	}
 	e, err := srv.Endpoint()
 	if err != nil {
@@ -112,13 +153,11 @@ func testClient(t *testing.T, srv *Server) {
 			t.Fatal(err)
 		}
 		resp, err := client.Do(req)
-		if test.path == "/index/notfound" && err != nil {
-			if e, ok := err.(*errors.Error); ok && e.Code == http.StatusNotFound {
-				continue
-			}
+		if errors.Code(err) != test.code {
+			t.Fatalf("want %v, but got %v", test, err)
 		}
 		if err != nil {
-			t.Fatal(err)
+			continue
 		}
 		if resp.StatusCode != 200 {
 			_ = resp.Body.Close()
@@ -140,13 +179,11 @@ func testClient(t *testing.T, srv *Server) {
 	for _, test := range tests {
 		var res testData
 		err := client.Invoke(context.Background(), test.method, test.path, nil, &res)
-		if test.path == "/index/notfound" && err != nil {
-			if e, ok := err.(*errors.Error); ok && e.Code == http.StatusNotFound {
-				continue
-			}
+		if errors.Code(err) != test.code {
+			t.Fatalf("want %v, but got %v", test, err)
 		}
 		if err != nil {
-			t.Fatalf("invoke  error %v", err)
+			continue
 		}
 		if res.Path != test.path {
 			t.Errorf("expected %s got %s", test.path, res.Path)