egg-errors

[![NPM version][npm-image]][npm-url]
[![Test coverage][codecov-image]][codecov-url]
[![Known Vulnerabilities][snyk-image]][snyk-url]
[![npm download][download-image]][download-url]

[npm-image]: https://img.shields.io/npm/v/egg-errors.svg?style=flat-square
[npm-url]: https://npmjs.org/package/egg-errors
[codecov-image]: https://codecov.io/gh/eggjs/egg-errors/branch/master/graph/badge.svg
[codecov-url]: https://codecov.io/gh/eggjs/egg-errors
[snyk-image]: https://snyk.io/test/npm/egg-errors/badge.svg?style=flat-square
[snyk-url]: https://snyk.io/test/npm/egg-errors
[download-image]: https://img.shields.io/npm/dm/egg-errors.svg?style=flat-square
[download-url]: https://npmjs.org/package/egg-errors

Errors for Egg.js

egg-errors provide two kinds of errors that is Error and Exception.

- Exception is system error that egg will log an error and throw exception, but it will be catched by onerror plugin.
- Error is business error that egg will transform it to response.

Install

``bash
$ npm i egg-errors --save
`

Usage

Create an Error

`js
const { EggError, EggException } = require('egg-errors');
let err = new EggError('egg error');
console.log(EggError.getType(err)); // ERROR
`

Create an Exception

`js
err = new EggException('egg exception');
console.log(EggException.getType(err)); // EXCEPTION
`

You can import an error from an normal error object

`js
err = new Error('normal error');
console.log(EggError.getType(err)); // BUILTIN
err = EggError.from(err);
console.log(EggError.getType(err)); // ERROR
`

$3

Error can be extendable.

`js
const { EggBaseError } = require('egg-errors');

class CustomError extends EggBaseError {
constructor(message) {
super({ message, code: 'CUSTOM_CODE' });
}
}
`

or using typescript you can customize ErrorOptions.

`js
import { EggBaseError, ErrorOptions } from 'egg-errors';

class CustomErrorOptions extends ErrorOptions {
public data: object;
}
class CustomError extends EggBaseError {
public data: object;
protected options: CustomErrorOptions;

constructor(options?: CustomErrorOptions) {
super(options);
this.data = this.options.data;
}
}
`

Recommend use message instead of options in user land that it can be easily understood by developer, see http error.

$3

HTTP Errors is BUILTIN errors that transform 400 ~ 500 status code to error objects. HttpError extends EggBaseError providing two properties which is status and headers;

`js
const { ForbiddenError } = require('egg-errors');
const err = new ForbiddenError('your request is forbidden');
console.log(err.status); // 403
`

Support short name too:

`js
const { E403 } = require('egg-errors');
const err = new E403('your request is forbidden');
console.log(err.status); // 403
`

$3

FrameworkBaseError is for egg framework/plugin developer to throw framework error.it can format by FrameworkErrorFormater

FrameworkBaseError extends EggBaseError providing three properties which is module、serialNumber and errorContext

FrameworkBaseError could not be used directly, framework/plugin should extends like this

`js
const { FrameworkBaseError } = require('egg-errors');

class EggMysqlError extends FrameworkBaseError {
// module should be implement
get module() {
return 'EGG_MYSQL';
}
}

const err = new EggMysqlError('error message', '01', { traceId: 'xxx' });
console.log(err.module); // EGG_MYSQL
console.log(err.serialNumber); // 01
console.log(err.code); // EGG_MYSQL_01
console.log(err.errorContext); // { traceId: 'xxx' }
`

#### create frameworkError with formater

use the static method .create(message: string, serialNumber: string | number, errorContext?: any) to new a frameworkError and format it convenient

`js
const { FrameworkBaseError } = require('egg-errors');

class EggMysqlError extends FrameworkBaseError {
// module should be implement
get module() {
return 'EGG_MYSQL';
}
}

const err = EggMysqlError.create('error message', '01', { traceId: 'xxx' });
console.log(err.message);
// =>
framework.EggMysqlError: error message [ https://eggjs.org/zh-cn/faq/EGG_MYSQL/01 ]
`

$3

FrameworkErrorFormater will append a faq guide url in error message.this would be helpful when developer encountered a framework error

the faq guide url format: ${faqPrefix}/${err.module}/${err.serialNumber}, faqPrefix is https://eggjs.org/zh-cn/faq by default. can be extendable or set process.env.EGG_FRAMEWORK_ERR_FAQ_PERFIX to override it.

`js
const { FrameworkErrorFormater } = require('egg-errors');

class CustomErrorFormatter extends FrameworkErrorFormater {
static faqPrefix = 'http://www.custom.com/faq';
}
`

#### .format(err)

format error to message, it will not effect origin error

`js
const { FrameworkBaseError, FrameworkErrorFormater } = require('egg-errors');

class EggMysqlError extends FrameworkBaseError {
// module should be implement
get module() {
return 'EGG_MYSQL';
}
}

const message = FrameworkErrorFormater.format(new EggMysqlError('error message', '01'));
console.log(message);
// => message format like this
framework.EggMysqlError: error message [ https://eggjs.org/zh-cn/faq/EGG_MYSQL/01 ]
...stack
...
code: "EGG_MYSQL_01"
serialNumber: "01"
errorContext:
pid: 66568
hostname: xxx


// extends
class CustomErrorFormatter extends FrameworkErrorFormater {
static faqPrefix = 'http://www.custom.com/faq';
}
const message = CustomErrorFormatter.format(new EggMysqlError('error message', '01'));
console.log(message);
// =>
framework.EggMysqlError: error message [ http://www.custom.com/faq/EGG_MYSQL/01 ]
...
`

#### .formatError(err)

append faq guide url to err.message

`js
const { FrameworkBaseError, FrameworkErrorFormater } = require('egg-errors');

class EggMysqlError extends FrameworkBaseError {
// module should be implement
get module() {
return 'EGG_MYSQL';
}
}

const err = FrameworkErrorFormater.formatError(new EggMysqlError('error message', '01'));
console.log(err.message); // error message [ https://eggjs.org/zh-cn/faq/EGG_MYSQL/01 ]
`

$3

`
BaseError
|- EggBaseError
| |- EggError
| |- HttpError
| | |- NotFoundError, alias to E404
| | - ...
| |- FrameworkBaseError
| - CustomError
- EggBaseException
|- EggException
- CustomException
`

Questions & Suggestions

Please open an issue here.

License

MIT


Contributors

|
popomore
|
mansonchor
|
fengmk2
|
beliefgp
|
sm2017
|
| :---: | :---: | :---: | :---: | :---: |


This project follows the git-contributor spec, auto updated at Tue Feb 22 2022 11:32:47 GMT+0800`.