errors: add proto

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

errors/errors.go

@@ -6,6 +6,8 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"strconv"
+	"strings"
 )
 
 var (
@@ -238,3 +240,64 @@ func FromError(err error) *Error {
 
 	return Parse(err.Error())
 }
+
+// MarshalJSON returns error data
+func (e *Error) MarshalJSON() ([]byte, error) {
+	return e.Marshal()
+}
+
+// UnmarshalJSON set error data
+func (e *Error) UnmarshalJSON(data []byte) error {
+	return e.Unmarshal(data)
+}
+
+// ProtoMessage noop func
+func (e *Error) ProtoMessage() {}
+
+// Reset resets error
+func (e *Error) Reset() {
+	*e = Error{}
+}
+
+// String returns error as string
+func (e *Error) String() string {
+	return fmt.Sprintf(`{"id":"%s","detail":"%s","status":"%s","code":%d}`, e.ID, e.Detail, e.Status, e.Code)
+}
+
+// Marshal returns error data
+func (e *Error) Marshal() ([]byte, error) {
+	return []byte(e.String()), nil
+}
+
+// Unmarshal set error data
+func (e *Error) Unmarshal(data []byte) error {
+	str := string(data)
+	if len(data) < 41 {
+		return fmt.Errorf("invalid data")
+	}
+	parts := strings.FieldsFunc(str[1:len(str)-1], func(r rune) bool {
+		return r == ','
+	})
+	for _, part := range parts {
+		nparts := strings.FieldsFunc(part, func(r rune) bool {
+			return r == ':'
+		})
+		for idx := 0; idx < len(nparts); idx++ {
+			switch {
+			case nparts[idx] == `"id"`:
+				e.ID = nparts[idx+1][1 : len(nparts[idx+1])-1]
+			case nparts[idx] == `"detail"`:
+				e.Detail = nparts[idx+1][1 : len(nparts[idx+1])-1]
+			case nparts[idx] == `"status"`:
+				e.Status = nparts[idx+1][1 : len(nparts[idx+1])-1]
+			case nparts[idx] == `"code"`:
+				c, err := strconv.ParseInt(nparts[idx+1], 10, 32)
+				if err != nil {
+					return err
+				}
+				e.Code = int32(c)
+			}
+		}
+	}
+	return nil
+}

errors/errors.proto

@@ -0,0 +1,31 @@
+// Copyright 2021 Unistack LLC
+//
+// 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";
+
+package micro.errors;
+
+option cc_enable_arenas = true;
+option go_package = "go.unistack.org/micro/v3/errors;errors";
+option java_multiple_files = true;
+option java_outer_classname = "MicroErrors";
+option java_package = "micro.errors";
+option objc_class_prefix = "MERRORS";
+
+message Error {
+  string id = 1;
+  string detail = 2;
+  string status = 3;
+  uint32 code = 4;
+}