@sumor/api-middleware

api-middleware

A Sumor Cloud Tool.
More Documentation

API Middleware is a middleware for Node.JS. It can easily expose function to api, and validate parameters

Installation

npm i @sumor/api-middleware --save

Prerequisites

Node.JS version

Require Node.JS version 18.x or above

require Node.JS ES module

As this package is written in ES module, please change the following code in your package.json file:

{
  "type": "module"
}

Usage

Basic Usage

• Add a file named plus.js in your project folder api

export default async (context, req, res) => {
  const { data } = context
  const { a, b } = data
  return a + b
}

• [Optional] Add a config file named plus.json in your project folder api

{
  "name": "plus",
  "parameters": {
    "a": {
      "name": "parameter a",
      "type": "number",
      "length": 3
    },
    "b": {
      "name": "parameter b",
      "type": "number"
    }
  }
}

• Add the following code in your index.js file

import express from 'express'
import apiMiddleware from '@sumor/api-middleware'

const app = express()

await apiMiddleware(app, process.cwd() + '/api')

app.listen(3000, () => {
  console.log('Server is running on http://localhost:3000')
})

• run index.js

node index.js

• Test the api

curl -X POST http://localhost:3000/plus -H "Content-Type: application/json" -d '{"a": 1, "b": 2}'

or use browser to open http://localhost:3000/plus?a=1&b=2

Options for apiMiddleware

import express from 'express'
import apiMiddleware from '@sumor/api-middleware'

const app = express()

await apiMiddleware(app, process.cwd() + '/api', {
  prefix: '/api',
  prepare: async context => {
    // do something before api
  },
  finalize: async (context, result) => {
    // do something after api
  },
  exception: async (context, error) => {
    // handle error
  }
})
app.listen(3000, () => {
  console.log('Server is running on http://localhost:3000')
})

More Config File Types

yaml

You can use yaml file to define config file, replace plus.json with plus.yml

type only support number, string, boolean, array, object

name: plus
parameters:
  a:
    name: parameter a
    type: number
    length: 3
  b:
    name: parameter b
    type: number

config.js

For support js function in config file, you can use config.js file, replace plus.json with plus.config.js

export default {
  name: 'plus',
  parameters: {
    a: {
      name: 'parameter a',
      type: 'number',
      length: 3
    },
    b: {
      name: 'parameter b',
      type: 'number',
      rule: [
        {
          code: 'TOO_BIG',
          message: 'b should be less than 100',
          function: function (value) {
            return value < 100
          }
        }
      ]
    }
  }
}

Parameter Rule

You can reference below example to apply rules to parameters

{
  "name": "plus",
  "parameters": {
    "a": {
      "name": "parameter a",
      "type": "number",
      "length": 3,
      "rule": [
        {
          "code": "GREATER_THAN_0",
          "expression": "^[1-9][0-9]*$",
          "message": "must be greater than 0"
        }
      ],
      "i18n": {
        "zh": {
          "GREATER_THAN_0": "必须大于0"
        }
      }
    },
    "b": {
      "name": "parameter b",
      "type": "number"
    }
  }
}

For more usage, please reference Validator

context

data

It includes all parameters passed in the request

file upload will be parsed as below object:

• name uploaded file name
• size uploaded file size(bytes)
• mime uploaded file mime type(e.g. image/png)
• encoding uploaded file encoding(e.g. 7bit)
• path uploaded file path

exposeApis

It includes all exposed apis