express-requirements

An express.js middleware to validate whatever comes into your NodeJS API. It works with node-validator.

Installation

npm install express-requirements

Usage

Our project

Let's admit that we have the following files tree :

|-- app.js
|-- routes
    |-- route.js
    |-- route.req.js

What is route.req.js ?

This file contains all of the requirements for one or multiple route(s). It is up to you.

You can rename this file as long as you keep the .req.js extension. Here it is an example of requirements file :

module.exports = {
    // Here you give a name to your route requirements
    my_route: {
        // Param firstName is required and must be alpha
        firstName: {
            required: true,
            isAlpha: true
        },
        // ...
    }
}

How to apply my requirements ?

First of all, let's create a basic NodeJS server like that :

// app.js
var express = require('express');
var app = express();
 
var bodyParser = require('body-parser');
var requirements = require('express-requirements'); // Require the module
 
app.use(bodyParser.json());
 
// Give the requirements root folder to the module
// Usually, you can use the routes root folder
app.use(requirements.use(__dirname + '/routes'));
 
app.use('/', require('./routes/route'));
 
app.listen(8888);

Finally, go to your route.js file to create a very basic route :

// route.js
var express = require('express');
var router = express.Router();
var requirements = require('express-requirements');
 
router.get('/test', requirements.validate('route.my_route'), function(req, res, next) {
  return res.status(200).json({
    success: true
  });
});

That's it ! Now, everytime the /test route will be call, express-requirements will validate fields according to the .req.js file.

What if I have another files tree ?

Let's change our files tree a little :

|-- app.js
|-- routes
    |-- route.js
    |-- requirements
        |-- route
            |-- main.req.js

The only thing which is going to change is the route.js file :

// route.js
var express = require('express');
// ...
 
router.get('/test', requirements.validate('requirements.route.main.my_route'), function(req, res, next) {
  // ...
});

When you specify the requirements file to use, the element located after the last point is always the name of your route inside the .req.js file.

In a nutshell: you can organize your files tree as you want.

Syntax

Basic

my_route: {
    firstName: {
        required: true, // Default error message will be 'missing_firstName_parameter'
        isAlpha: true, // Default error message will be 'bad_request'
        // ...
    }
}

Custom error message/code

my_route: {
    firstName: {
        required: {
            errorMessage: 'You must enter a firstName'
            // Default code is 400
        },
        isAlpha: {
            errorMessage: 'Only alpha in your %@', // Use %@ to retrieve the property name (here it is 'firstName')
            errorCode: 403
        },
        // ...
    }
}

Scopes

my_route: {
    // Only checks into the headers scope
    _headers: {
        'Authorization': { required: true }
        'Content-Type': { required: true }
    },
    // Only checks into the params scope
    _params: {
        id: { required: true, notEmpty: true }
    },
    // Only checks into the body scope
    _body: {
        username: { required: true, notEmpty: true }
    }
}

Inheritance/Override

my_route: {
    firstName: { required: true, notEmpty: true, isAlpha: true },
    lastName: {
        required: true,
        isAlpha: { errorMessage: '%@ must be alpha' }
    }
},
 
other_route: {
    firstName: { _inheritFrom: 'my_route' }, // Now firstName has 'notEmpty' and 'isAlpha' as requirements
    lastName: {
        _inheritFrom: 'my_route',
        isAlpha: {  errorMessage: 'Error message overriden for %@' }, // You can override any requirement component ...
        notEmpty: true // ... and even add new one
    }
}

Note that for any inheritance, required is never included. You have to add it to the inherited route by yourself.

Validator parameters

my_route: {
    firstName: { required: true, isAlpha: true },
    phoneNumber: {
        matches: {
            _parameter: '[0-9]{3}\\-[0-9]{3}\\-[0-9]{4}', // Use _parameter to pass any parameter to a validator
            errorMessage: 'wrong_%@_format'
        }
    }
}

Validators

You can use all the validators which compose node-validator. You also have these :

isArray

isArray: true

isArray: {
    notEmpty: { errorMessage: 'error', errorCode: 400 }
    content: { // Check the content of the array
        isAlpha: { errorMessage: 'must_be_alpha' },
        // You can add other validators for the array content
    }
    
    // Usual parameters
    errorMessage: 'error',
    errorCode: 400
}

Don't use any other validator than notEmpty, it won't work.

notEmpty

notEmpty: true

notEmpty: {
    errorMessage: 'error',
    errorCode: 400
}

What's next ?

• Posibility to add your own validators
• Add unit tests for the custom options