apichainer

apichainer is a Node.js package for providing an Express middleware chaining library that supports JSON schema validation, authentication, logging, CORS, and parallel execution with customizable options.

• Installation
• Usage
  • Simple Usage (Enable Validation and CORS)
  • Enable Middleware for a Single Route
  • Enabling Parallel Execution
  • Configuring Validation
  • Enabling Parallel Execution
• Configuration Options
• Demo
• License

Installation

This is a Node.js module available through the npm registry. Installation is done using the npm install command:

$ npm install apichainer
```

## Usage

### Simple Usage (Enable Validation and CORS)

#### Chain middleware for an Express route with validation and CORS support:

```javascript
var express = require('express');
var APIChainer = require('apichainer');

var app = express();

app.use(express.json());

var chain = new APIChainer()
  .cors()
  .validate({
    type: 'object',
    properties: { name: { type: 'string' } },
    required: ['name'],
  })
  .use(function (req, res, next) {
    res.json({ msg: 'This is CORS-enabled with validation!' });
  });

app.post('/api', function (req, res) {
  chain.execute(req, res);
});

app.listen(3000, function () {
  console.log('Server listening on port 3000');
});

Enable Middleware for a Single Route

Apply authentication and validation to a specific route:

var express = require('express');
var APIChainer = require('apichainer');

var app = express();

app.use(express.json());

var chain = new APIChainer()
  .auth({ token: 'secret' })
  .validate({
    type: 'object',
    properties: { name: { type: 'string' } },
    required: ['name'],
  })
  .use(function (req, res, next) {
    res.json({ msg: 'This is authenticated and validated for a single route' });
  });

app.post('/api', function (req, res) {
  chain.execute(req, res);
});

app.listen(3000, function () {
  console.log('Server listening on port 3000');
});

Enabling Parallel Execution

Run middleware concurrently for improved performance:

var express = require('express');
var APIChainer = require('apichainer');

var app = express();

app.use(express.json());

var chain = new APIChainer({}, true) // Enable parallel execution
  .log({ level: 'info' })
  .cors()
  .use(function (req, res, next) {
    // Simulate async task
    setTimeout(function () {
      res.json({ msg: 'Parallel execution completed' });
    }, 1000);
  });

app.get('/api', function (req, res) {
  chain.execute(req, res);
});

app.listen(3000, function () {
  console.log('Server listening on port 3000');
});

Configuration Options

• validate(schema):

  • Validates req.body against a JSON Schema.
  • Returns <property> is required for missing or invalid required properties.
  • Example: { type: 'object', properties: { name: { type: 'string' } }, required: ['name'] }

• validate(schema):

  • Adds token-based authentication.
  • Options:
  • Options:
  • Options:
  • token: Required string (e.g., secret).
  • header: Optional string (e.g., authorization, defaults to authorization).

• auth(options):

  • Adds token-based authentication

  • Options

    • token: Required string (e.g., secret)
    • header: Optional string (e.g., authorization, default to authorization).

• log(options):

  • Logs request details (method, URL, timestamp).

  • Options

    • level: info, warn, or error (default to info).

• parallel:

  • Enable parallel middleware execution by setting parallel: true in the constructor.
  • Example: new APIChainer({},true)

The default configuration is the equivalent of:

Demo

A demo illustrating apichainer usage with Express is available in the repository:

$ git clone https://github.com/vivek3410/apichainer
$ cd apichainer
$ npm install
$ node examples/express-example.js

Test with curl:

$ curl -X POST http://localhost:3000/api \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer secret" \
  -d '{"name":"John"}'

Expected response:

 { "msg": "This is CORS-enabled with validation!" }

License

MIT License