错误码管理

RK 推荐的 RPC 标准错误类型。

概述

设计一个合理的 API 是一件不容易的事情，同时，API 还会产生各种不同的错误。

为了能让 API 使用者对于 API 的错误有一个清晰的视图，定义一个标准的 RPC 错误类型是非常重要的事情。

当使用 rk-boot 的时候，panic 中间件会默认加载到服务中，中间件会从 panic 中恢复，并且返回[内部错误]给用户。 默认使用 Google 样式的错误。

{
  "error":{
    "code":500,
    "status":"Internal Server Error",
    "message":"Panic occurs",
    "details":[
      "panic manually"
    ]
  }
}

• Amazon 样式

{
    "response":{
        "errors":[
            {
                "error":{
                    "code":500,
                    "status":"Internal Server Error",
                    "message":"Panic occurs",
                    "details":[
                        "panic manually"
                    ]
                }
            }
        ]
    }
}

• 自定义样式

请参照后面的例子。

快速开始

• 安装

$ go get github.com/rookie-ninja/rk-boot/v2
$ go get github.com/rookie-ninja/rk-grpc/v2

RPC 中返回错误

本例子中，介绍如何返回错误给 API 使用者的[最佳实践]

func (server *GreeterServer) Greeter(ctx context.Context, request *greeter.GreeterRequest) (*greeter.GreeterResponse, error) {
    return nil, rkgrpcerr.Unimplemented("Trigger manually!", errors.New("this is detail")).Err()
}

```shell script $ curl localhost:8080/v1/hello { "error":{ "code":501, "status":"Not Implemented", "message":"Trigger manually!", "details":[ { "code":12, "status":"Unimplemented", "message":"[from-grpc] Trigger manually!" }, { "code":2, "status":"Unknown", "message":"this is detail" } ] } }

### Amazon 样式错误
- boot.yaml

```yaml
grpc:
  - name: greeter              
    enabled: true              
    port: 8080
#   gwPort: 8081                  # 可选项，如果不指定，会使用与 port 一样的端口
    enableRkGwOption: true
    middleware:
      errorModel: amazon

{
  "response":{
    "errors":[
      {
        "error":{
          "code":501,
          "status":"Not Implemented",
          "message":"Trigger manually!",
          "details":[
            {
              "code":12,
              "status":"Unimplemented",
              "message":"Trigger manually!"
            },
            {
              "code":2,
              "status":"Unknown",
              "message":"this is detail"
            }
          ]
        }
      }
    ]
  }
}

自定义样式

请实现如下两个接口，并注册到 Entry 中。

type ErrorInterface interface {
    Error() string

    Code() int

    Message() string

    Details() []interface{}
}

type ErrorBuilder interface {
    New(code int, msg string, details ...interface{}) ErrorInterface

    NewCustom() ErrorInterface
}

• main.go

package main

import (
    "context"
    "errors"
    "fmt"
    "github.com/rookie-ninja/rk-boot/v2"
    "github.com/rookie-ninja/rk-demo/api/gen/v1"
    "github.com/rookie-ninja/rk-entry/v2/error"
    "github.com/rookie-ninja/rk-entry/v2/middleware"
    "github.com/rookie-ninja/rk-grpc/v2/boot"
    "github.com/rookie-ninja/rk-grpc/v2/boot/error"
    "google.golang.org/grpc"
    "net/http"
)

func main() {
    boot := rkboot.NewBoot()

    // register grpc
    entry := rkgrpc.GetGrpcEntry("greeter")
    entry.AddRegFuncGrpc(registerGreeter)
    entry.AddRegFuncGw(greeter.RegisterGreeterHandlerFromEndpoint)

    // Bootstrap
    boot.Bootstrap(context.TODO())

    // Set default error builder after bootstrap
    rkmid.SetErrorBuilder(&MyErrorBuilder{})

    // Wait for shutdown sig
    boot.WaitForShutdownSig(context.TODO())
}

func registerGreeter(server *grpc.Server) {
    greeter.RegisterGreeterServer(server, &GreeterServer{})
}

//GreeterServer GreeterServer struct
type GreeterServer struct{}

// Hello response with hello message
func (server *GreeterServer) Hello(_ context.Context, _ *greeter.HelloRequest) (*greeter.HelloResponse, error) {
    return nil, rkgrpcerr.Unimplemented("Trigger manually!", errors.New("this is detail")).Err()
}

type MyError struct {
    ErrCode    int
    ErrMsg     string
    ErrDetails []interface{}
}

func (m MyError) Error() string {
    return fmt.Sprintf("%d-%s", m.ErrCode, m.ErrMsg)
}

func (m MyError) Code() int {
    return m.ErrCode
}

func (m MyError) Message() string {
    return m.ErrMsg
}

func (m MyError) Details() []interface{} {
    return m.ErrDetails
}

type MyErrorBuilder struct{}

func (m *MyErrorBuilder) New(code int, msg string, details ...interface{}) rkerror.ErrorInterface {
    return &MyError{
        ErrCode:    code,
        ErrMsg:     msg,
        ErrDetails: details,
    }
}

func (m *MyErrorBuilder) NewCustom() rkerror.ErrorInterface {
    return &MyError{
        ErrCode:    http.StatusInternalServerError,
        ErrMsg:     "Internal Error",
        ErrDetails: []interface{}{},
    }
}

{
    "ErrCode":501,
    "ErrMsg":"Trigger manually!",
    "ErrDetails":[
        {
            "code":12,
            "status":"Unimplemented",
            "message":"Trigger manually!"
        },
        {
            "code":2,
            "status":"Unknown",
            "message":"this is detail"
        }
    ]
}

Cheers