juv

Javascript Universal Validation

for use in production please wait till version 0.8.0!

JUV is a clean, neat, easy to use and professianl set of express.js middlewares that use a developer-defined model to validate and sanitize input from the client and the advantage is to make a definition of view-models that makes the architecture model more rational and reliable.

Installation

To have npm and work with this package first of all make sure you have installed Nodejs, then install express using this npm command:

npm i express

then install JUV using npm (make sure that you have Node.js 8.x or newer):

npm i juv

Basic guide

It's recommended that you have basic knowledge of the express.js module before you go on with this guide.

Let's get started by writing a basic route to say hello to a set of names that matches our policy. Then, you want to make sure that you validate the input and report any errors before accepting them.

const express = require('express')
const app = express()
const juv = require('juv')
// POLICY: username should start with an a,b or c and continue with atleast four words or numbers up to 10!
app.get('/:username', juv({ username: u => u.match(/^[abc][\w\d]{4,10}$/gi) }), (req, res) => {
  if (req.error)
    return res.status(401).send(req.error)
  res.send(`Hi ${req.params.username}`)
})
app.listen(3000, () => console.log(`Example app listening on port 3000`))

After copy the file into app.js, run it using: node app, then open this link: http://localhost:3000/abba on any browser to see the result! Here the username is abba.
Voila! Now, whenever a request that includes invalid username fields is submitted, your server will respond erro with status 401 (means invalid parameter) along with the the custome message you defined and send by .send(req.error).

The validations are user-defined so you can have your model for custom validation, let's call it view-models! Works beautifully with req.params and req.body.

Explain

The juv from const juv = require('juv') is a constructor function that takes an object as a model of the parameters for validation! The model could contains json models for both request and response by passing { reqModel: {} , resModel: {} }, but if the reqModel left as empty object or undefined then the model of request would be an empty object like {}. If the resModel left empty then it would be the default one described later on table of #obejct and functoins!

If the model didn't contain reqModel and resModel and just contains an object of the parameters then the model itself will place as reqModel that makes it easear for use as example!
I have deleted the resModel for now... but it'll be back on version 0.7.0! stay tuned!

Use view-model sample

The extreme, wonderful and enjoyable thing about JUV is that it makes you able to define view-models and control every single parameter comes along like so:
In helloViewModel.js file:

module.exports = {
  username: u => u.match(/^[abc][\w\d]{4,10}$/gi) 
}

In app.js file:

const viewModel = require('./helloViewModel.js')
app.use(juv(viewModel)) // juv takes view model
app.post('/:username', (req, res) => {
  if (req.error)
    return res.status(401).send(req.error)

  // your code 

  res.send(`Hi ${req.params.username}`)
})

objects and functions

| name | type | default | description | |---------------|----------|------------------------------------------------------------|--------------------------------------------------------------------------------------| | req.error | string | undefined | if validation fails it would be a string of messages of validations among all params | | req.model | object | {} | an object for use as a variable to set the I/O in a beautiful way |

I have deleted the resModel for now... but it'll be back on version 0.7.0! stay tuned!

Contributions

Please contribute!
We profoundly accept your help. For contribute, please fork, and for merge, request a pull on develop branch!