Express-proxy-mock NPM

express-proxy-mock

Description

Middleware for express, mainly used for proxy requests and MOCK data. It can be used for all development projects that start services with webpack, vite, and other express-based servers. This middleware should only be used for development.

Some benefits of using this middleware include:

Proxy requests and MOCK data
Visual management of MOCK data and proxy functions
Proxy support for global proxy and custom proxy for a specific URL
Switch between proxy forwarding or MOCK data for a specific URL at any time
Return different MOCK data based on different parameters
Quickly save the data returned by the most recent request as MOCK data

Getting Started

First, install the module:

npm install express-proxy-mock --save-dev

Usage

webpack.config.js

module.exports = {
  //...
  devServer: {
    setupMiddlewares(middlewares, devServer) {
      devServer.app.use(proxyMockMiddleware({
        apiRule: '/api/*',
        lang: 'en'
      }))
      return middlewares
   }
  },
};

express

const { proxyMockMiddleware } = require("express-proxy-mock");
const express = require("express");
const app = express();

app.use(
  proxyMockMiddleware({
    // express-proxy-mock options
  }),
);

app.listen(3000, () => console.log("Example app listening on port 3000!"));

Open the browser at http://localhost:3000/config to see the configuration interface for proxy and MOCK data.

Refer to below for usage examples with vite, webpack, and vueConfig.

Options

Name	Type	Default	Description
`apiRule`	`string`	`/api/*`	Global proxy matching rule, default is all requests starting with api
`https`	`boolean`	`true`	Whether to proxy https requests.
`configPath`	`string`	`/config`	Address to open the configuration page, default is http://localhost:3000/config
`cacheRequestHistoryMaxLen`	`number`	`30`	Maximum number of cached request data
`lang`	`string`	`zh`	lang (en,zh)
`buttonPosition`	`'top' \\| 'middle' \\| 'bottom' \\| string`	`bottom`	Position of the configuration button (Only works in Vite). You can use 'top', 'middle', 'bottom' or coordinate string like '100,100'

Other Servers

Here are examples of usage with other servers.

Webpack >= 5.0

Modify webpack.config.js

module.exports = {
  //...
  devServer: {
    ...
  },
  plugins: [
     // In webpack, the plugin will get the devServer and inject the proxy, so no need to configure devServer separately
      new WebpackProxyMockPlugin({
        apiRule: '/api/*',
        lang: 'zh'
      })
  ]
};

Webpack <= 4+

// vue.config.js or other webpack config files 
const { proxyMockMiddleware } = require('express-proxy-mock')

module.exports = {
  //...
   devServer: {
     before(app) {
      app.use(proxyMockMiddleware({
        apiRule: '/api/*',
        lang: 'en'
      }))
    }
   }
  };

vite

// vite.config.js
import { defineConfig } from 'vite'
import { ViteProxyMockPlugin } from 'express-proxy-mock'

export default defineConfig({
  plugins: [
    ViteProxyMockPlugin({
      apiRule: '/api/*',
      lang: 'en',
      buttonPosition: 'bottom', // Optional: 'top', 'middle', 'bottom' or coordinate like '100,100'
    })
  ]
})

vue.config.js

const proxyMockPlugin = new WebpackProxyMockPlugin({
        apiRule: '/api/*',
        lang: 'zh'
      })
module.exports = {
  //...
  devServer: {
    setupMiddlewares: (middlewares, devServer) => {
      // In vue config, because vue-cli injects devServer after webpack compilation is complete, the plugin cannot get the devServer configuration, so you need to manually inject the proxy middleware
      proxyMockPlugin.setupDevServer(devServer.app);
      return middlewares;
    }
  },
  plugins: [
      proxyMockPlugin
  ]
};

Environment Variables

The proxy supports environment variables management, which allows you to:

Create multiple environment configurations
Bind environment variables to specific proxies
Quick switch between different environments
Auto clear browser cache when switching environments

Enabling Environment Variables

To enable the environment variables feature, you need to:

Use webpack with DefinePlugin
Add the WebpackProxyMockPlugin to your webpack configuration

How to use environment variables

Click the "+" button next to the environment selector to create a new environment
Add key-value pairs in the environment configuration
You can bind an environment to a proxy in the proxy settings
When switching environments, the system will prompt whether to clear the browser cache