Express Rest Tools

Install

npm install express-rest-tools

• Configulation
• Throw error
• Resonse json format
• Sever scrips
• Utilities
• Middlewares
• API Documentation with swagger

Configulation

Config key	Default	Type	Description
port	4000	Number	Development server port
corsOptions	{}	Object	Node.js CORS middleware
logger	false	Bool, Function	Create log format of each activities
fetchErrorHandler	false	Bool, Function	Handle api response that should be an error (Function must return boolean)
fetchMessageErrorHandler	false	Bool, Function	Handle error message from api response
reasons	Resons Types	Object	Reason code and message
swaggerDefinition	{}	Object	A document that defines or describes an API see more

Setup and config app in server.js

import { setConfig, useRouter, startServer } from 'express-rest-tools'
import routes from './routes'
 
const reasons = {
  6: 'Custom description',
  7: 'Custom description'
}
 
const fetchErrorHandler = res => {
  if (res.status !== 200) return true
  return false
}
 
const fetchMessageErrorHandler = res => {
  throw Object({
    type: 6,
    th: 'Message',
    en: 'Message',
    technical: 'Message'
  })
}
 
const logger = (type, datas) => {
  if (type === 'access') {
    return { type }
  }
 
  if (type === 'activity') {
    return { type }
  }
 
  if (type === 'response') {
    return { type }
  }
 
  if (type === 'error') {
    return { type }
  }
}
 
setConfig({
  port: 4000,
  corsOptions: {},
  reasons,
  swaggerDefinition: {},
  fetchErrorHandler,
  fetchMessageErrorHandler,
  logger
})
 
useRouter(routes)
 
startServer()

Reasons Types

// Default
{
  0: 'Success',
  1: 'Failed to fetch service',
  2: 'API error',
  3: 'Validation rules error',
  4: 'File system error',
  5: 'Application error'
}
 
// Add
setConfig({
  reasons: {
    6: 'Custom descirption',
    7: 'Custom descirption'
  }
})

Throw error

Use throw to return error message

throw Object({
  type: 5, // Reason code
  th: 'Message',
  en: 'Message',
  technical: 'Message'
})

Resonse json format

{
  "transactionID": "G2PC01RKZJSU42YEH-2019/03/04|15:57:44",
  "serviceResult": {
    "status": "ERROR",
    "code": 1,
    "description": "Failed to fetch service"
  },
  "message": {
    "th": "Message",
    "en": "Message",
    "technical": "Message"
  },
  "data": null
}

Server scripts

Dev server

$ npm run dev

Production server

$ npm run start

Testing

$ npm run test
$ npm run test:watch

Listing

$ npm run lint

Utilities

Name	Description
asyncHandler	Supported throw error in async function then the error will be handle by middleware
createFetcher	Fetching API and handle error (try/catch) under hood
useActivity	Log activity

Example

asyncHandler

Wrap controller function and use res({}) to return data

import { asyncHandler } from 'express-rest-tools/lib/utils'
 
const posts = asyncHandler((req, res) => {
  const postData = []
  res({
    data: postData
  })
})

res({
  headers: {},
  data: any
})

createFetcher

Use axios options

import { createFetcher } from 'express-rest-tools/lib/utils'
 
const fetchPosts = createFetcher({
  method: 'get',
  url: 'https://jsonplaceholder.typicode.com/posts'
})
 
const posts = await fetchPosts()

Fetch soap

import { createFetcher } from 'express-rest-tools/lib/utils'
 
const fetchSoapAPI = createFetcher({
  method: 'post',
  headers: {
    'Content-Type': 'text/xml;charset=UTF-8'
  },
  url: 'http://api',
  data: `xml`
})
 
const soap = await fetchSoapAPI()

useActivity

import { useActivity } from 'express-rest-tools/lib/utils'
 
useActivity({ name: 'fetchPosts' })

Middlewares

Name	Description
cache	Cache response in memory
validate	Validate request with rules

cache

import { cache } from 'express-rest-tools/lib/middlewares'
 
// cache(duration)
 
router.get('/posts', cache(5000, 'prefix'), controller.posts)

Clear Cache

import { clear, clearAll } from 'express-rest-tools/lib/middlewares/cache'
 
clear('prefix')
 
clearAll()

validate

Using [Joi](https://www.npmjs.com/package/joi) validator for JavaScript objects.

import { validate } from 'express-rest-tools/lib/middlewares'
import Joi from 'joi'
 
// const rules = {
//   query: {},
//   params: {},
//   body: {}
// }
 
const rules = {
  query: {
    name: Joi.string().required(),
    age: Joi.number().required()
  }
}
 
// Use a function to get request data
 
const rules = {
  query: req => ({
    name: Joi.string().required(),
    age: Joi.number().required()
  })
}
 
router.get('/posts', validate(rules), controller.posts)

Add Middlewares

import { useMiddleware } from 'express-rest-tools'
 
useMiddleware(yourMiddleware)

API Documentation

The Swagger UI page is https://server/api-docs

Example to write document with Swagger

/**
 * @swagger
 * /users:
 *   get:
 *     description: Returns users
 *     tags: [Users]
 *     parameters:
 *       - in: query
 *         name: "name"
 *         required: true
 *         type: "string"
 *     responses:
 *       200:
 *         description: Success
 */
router.get('/users', controller)