node-input-validator/README.md

# Validation Library

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Validation library for node.js

NIV (Node Input Validator) is a validation library for node.js. You can also extend library to add custom rules.

**Note**: For use case of any rule, please check test cases, If you have any doubt or confusion with documentation or rule behaviour.

## Installation

```shell
npm i node-input-validator
```

## Features

- large collection of rules
- add your own custom rules
- supports nested inputs
- declare rules as strings or array
- post validation rules
- modify or add new messages in your own language
- change attribute names globally or locally
- current supported languages: English, Persian(farsi)

## Usage

- [Example](#simple-example)  
- [With express](#with-in-express-application)  
- [With async/await](#with-async-await)  
- [Koa middleware](#for-koa2)  
- [Object validation examples](#objects-validation)  
- [Array validation examples](#array-validation)  
- [Add/Modify messages](#add-or-modify-messages)  
- [Change default language examples](#set-default-language)  
- [Toggle multiple errors](#toggle-multiple-errors-support)  
- [Change attribute names in messages examples](#set-attribute-nicecustom-name)  
- [Add custom rules](#add-your-own-custom-validation-rules)  
- [Rules](#rules)  

### Simple Example  

```javascript
const { Validator } = require('node-input-validator');

const v = new Validator(
  { name: '' },
  { name: 'required|minLength:5' },
);

v.check().then(function (matched) {
  console.log(matched);
  console.log(v.errors);
});
```

### With in express application

```javascript
const { Validator } = require('node-input-validator');

app.post('login', function (req, res) {
  const v = new Validator(req.body, {
    email: 'required|email',
    password: 'required'
  });

  v.check().then((matched) => {
    if (!matched) {
      res.status(422).send(v.errors);
    }
  });
});
```

### With async-await

```javascript
const { Validator } = require('node-input-validator');

router.post('login', async (ctx) => {
  const v = new Validator(ctx.request.body, {
    email: 'required|email',
    password: 'required'
  });

  const matched = await v.check();

  if (!matched) {
    ctx.status = 422;
    ctx.body = v.errors;
    return;
  }
});
```

### For Koa2

#### Attach koa middleware

```javascript
const niv = require('node-input-validator');

// keep this under your error handler
app.use(niv.koa());
```

#### Then in controller

```javascript
// if validation fails, this will auto abort request with status code 422 and errors in body
await ctx.validate({
  name: 'required|maxLength:50',
  username: 'required|maxLength:15',
  email: 'required|email',
  password: 'required'
});

// validation passes
// do some code
```

#### With custom inputs

```javascript
// if validation fails, this will auto abort request with status code 422 and errors in body
await ctx.validate({
  name: 'required|maxLength:50',
  username: 'required|maxLength:15',
  email: 'required|email',
  password: 'required'
}, ctx.request.body);

// validation passes
// do some code
```

#### With custom inputs and custom messages

```javascript
// if validation fails, this will auto abort request with status code 422 and errors in body
await ctx.validate({
  name: 'required|maxLength:50',
  username: 'required|maxLength:15',
  email: 'required|email',
  password: 'required'
}, ctx.request.body, { email: 'E-mail is required' });

// validation passes
// do some code
```

#### In case you wants control over validator, Then use

```javascript
// if validation fails, this will auto abort request with status code 422 and errors in body
const v = await ctx.validator(ctx.request.body, {
  name: 'required|maxLength:50',
  username: 'required|maxLength:15',
  email: 'required|email',
  password: 'required'
});

// in case validation fails
if (v.fails()) {
  ctx.status = 422;
  ctx.body = v.errors;
  return;
}

// do some code
```

##### This method (ctx.validator(inputs, rules, messages={})) also support same options as like ctx.validate

### Objects Validation

#### Example 1

```javascript
const v = new Validator(
  {
    product: {
      id: '1',
      name: '',
      price: '',
      active: 'yes',
    }
  },
  {
    'product': 'required|object',
    'product.id': 'required|integer',
    'product.name': 'required',
    'product.price': 'required|integer',
    'product.active': 'required|integer'
  },
);

const matched = await v.check();
```

### Array Validation

#### Example 1

```javascript
let v = new Validator(
  {
    roles: ['admin', 'manager', 'member']
  },
  {
    'roles': 'required|array',
    'roles.*': 'required|string'
  },
);

let matched = await v.check();
```

#### Example 2

```javascript
let v = new Validator(
  {
    plan: [
      { price: '25', title: 'OK' },
      { price: '', title: '' },
      { price: '30' },
      { price: '', title: 'Title' }
    ]
  },
  {
    'plan': 'required|array',
    'plan.*.price': 'required|integer',
    'plan.*.title': 'required'
  },
);
let matched = await v.check();
```

### Add or Modify messages

Placeholder in messages, :attribute will be replaced with field/attribute name, :value with field value and :arg0, :arg1 ...n with arguments passed to rule.

#### Add/Update rule based messages

```javascript
const niv = require('node-input-validator');
/**
 * @param {Object} messages
 * @param {string?=en} language
 */
niv.extendMessages({
  required: 'The :attribute field must not be empty.',
  email: 'E-mail must be a valid email address.',
  even: 'The value of the field must be even number.',
  status: 'Invalid status'
}, 'en');
```

#### Add custom messages

```javascript
const niv = require('node-input-validator');
//Note: Default language is English (en).
niv.customMessages({
  'username.required': 'When username attribute required rule failed.',
  username: 'Default message for username attribute.'
});
```

#### for message in another language

You can easliy add messages in another language.

```javascript
const niv = require('node-input-validator');
niv.extendMessages({
  required: ':attribute ਫੀਲਡ ਖਾਲੀ ਨਹੀਂ ਹੋਣਾ ਚਾਹੀਦਾ.',
}, 'pb');
```

### Set default language

```javascript
const niv = require('node-input-validator');
niv.setLang('pb');
```

### Toggle Multiple Errors Support

By default, Validator will run in bailable mode ie. break if some rule failed. You can change this behaviour:

#### Globally

```javascript
const niv = require('node-input-validator');
niv.bailable(false);
```

Now instead of breaking, it will continues apply other rules.

#### Errors example

```javascript
{
  name: [
    {
      rule: 'minLength',
      message: '...',
    },
    {
      rule: 'alpha',
      message: '...',
    }
  ]
}
```

#### Locally

To toggle multiple errors on specific instance only.

```javascript
const niv = require('node-input-validator');
const v = new niv.Validator(inputs, rules);
v.bail(false);
```

### Set attribute nice/custom name

You can also declare Nice Names / Custom Attributes names.

```javascript
const niv = require('node-input-validator');
niv.niceNames({
  phone: 'phone number',
  dob: 'Date of Birth'
});
```

If your are editing other languages, set lang parameter.

```javascript
const niv = require('node-input-validator');
niv.niceNames({
  phone: 'phone number',
  dob: 'Date of Birth'
},'fa');
```

In error messages you will get "phone number" instead of phone. For Example: In case required rule failed, Error message will be: The phone number field is mandatory.

#### For current instance only

```javascript
const niv = require('node-input-validator');

const v = new niv.Validator(inputs, rules);
v.niceNames({
  phone: 'phone number',
  dob: 'Date of Birth'
});
```

This will only change attribute names for current instance.

### Add your own custom validation rules

```javascript
// second params will be the instance of Validator
niv.extend('even', ({ value }) => {
  if ((parseInt(value) % 2) == 0) {
    return true;
  }
  return false;
});
```

#### Example of using other fileds in rule

```javascript
const niv = require('node-input-validator');

niv.extend('sumOfFields', ({ value, args }, validator) => {
  if (args.length !== 2) {
    throw new Error('Invalid seed for rule sumOfFields');
  }

  const anotherValue = Number(validator.inputs[args[0]]);

  const eq = Number(args[1]);

  if ((Number(value) + anotherValue) !== eq) {
    return false;
  }

  return true;
});

let v = new niv.Validator(
  { num1: '50', num2: '50' },
  { num1: 'sumOfFields:num2,100|required' },
);

let matched = await v.check();

assert.equal(matched, true);
```

#### Example of using async rules

```javascript
// use this rules as unique:seed
// unique:<Mongoose Model>,<Field Name>,<ID to Ignore, This is optional>

const niv = require('node-input-validator');
const mongoose = require('mongoose');

niv.extend('unique', async ({ value, args }) => {
  // default field is email in this example
  const filed = args[1] || 'email';

  let condition = {};

  condition[filed] = value;

  // add ignore condition
  if (args[2]) {
    condition['_id'] = { $ne: mongoose.Types.ObjectId(args[2]) };
  }

  let emailExist = await mongoose.model(args[0]).findOne(condition).select(field);

  // email already exists
  if (emailExist) {
    return false;
  }

  return true;
});

// example usage of upper extended rule

new niv.Validator({
  email: 'required|email|unique:User,email'
}, inputs);

// in case to ignore specific id

new niv.Validator({
  email: 'required|email|unique:User,email,5c2f29e9cefa7718a54f8ff1'
}, inputs);
```

## Rules

You can check test cases for rule usage/examples.

**required**  
The field under validation cannot be left blank.

```javascript
// should fail
new Validator(
  { name: '' },
  { name: 'required' },
);
```

**requiredIf:field,value**  
The field under validation cannot be left blank, if provided seed value equals to provided value seed.

```javascript
// requiredIf rule validation fails, becoz email cannot be left blank if age is 16
new Validator(
  { email: '', age: '16' },
  { email: 'requiredIf:age,16' },
);
```

**requiredNotIf:field,value**  
The field under validation may left blank, if provided seed value equals to provided value seed.

```javascript
// requiredNotIf rule validation fails, becoz transport must be present in case age is not 16
new Validator(
  { transport: '', age: '15' },
  { transport: 'requiredNotIf:age,16' },
);
```

**requiredWith:field**  
**requiredWith:field,field,field**  
 The field under validation may required in case provided seed present.

```javascript
// requiredWith rule validation fails, becoz email must in case age present.
new Validator(
  { email: '', age: '17' },
  { email: 'requiredWith:age' },
);
```

**requiredWithout:field**  
**requiredWithout:field,field,field**  
The field under validation may left blank in case provided seed present.

```javascript
// requiredWithout rule validation fails, becoz email is must in case phone,pan not provided.
new Validator(
  { email: '', username: '' },
  { email: 'requiredWithout:phone,pan', username: 'requiredWithout:email' },
);
```

**accepted**  
The field under validation must be yes, on, 1, or true.

**accepted:seeds**  
The field under validation must be accepted if value exists in provided seed.

**after:YYYY-MM-DD**  
The field under validation must be date after provided seed.

```javascript
new Validator(
  { joining: '' },
  { joining: 'required|after:2018-02-10' },
);
```

**alpha**  
The field under validation must be entirely alphabetic characters.

**alphaDash**  
The field under validation may have alpha-numeric characters, as well as dashes and underscores.

**alphaNumeric**  
The field under validation only contains letters and numbers.

**array**  
The field under validation must be an array.

**arrayUnique**  
<sub>Added in: v3.5</sub>  
The field under validation must be an array and must contains unique values. No need to use array rule. This rule will take care of that.

**arrayUniqueObjects:attributes**  
<sub>Added in: v3.5</sub>  
The field under validation must be an array and should have objects with unique attributes as per seed. No need to use array rule. This rule will take care of that.

**ascii**  
The field under validation only contains ascii characters.

**base64**  
The field under validation must be valid base64 encoded string.

**between:min,max**  
The field under validation must be betwwen min and max seed. This will work with number valus as well as with arrays using array count.

**boolean**  
**boolean:custom**  
The field under validation must be boolean (true, false, 'true', 'false', 0, 1, '0', '1') or in custom seed.

**contains:value**  
The field under validation must contains provided seeds.

```javascript
let v = new Validator({bio:'My profile is: example.com'}, {bio:'required|contains:profile'});
```

**creditCard**  
The field under validation must be valid credit card string.

**date**  
The field under validation must be a valid date (YYYY-MM-DD).

**dateAfterToday:number,unit**  
The field under validation must be a valid date after provided seed.

```javascript
new Validator(
  { expiry: '2019-02-28' },
  { expiry: 'required|dateAfterToday:2,days' },
);
```

see moment docs(https://momentjs.com/docs/#/manipulating/add/) for supported units.

**dateBeforeToday:number,unit**  
The field under validation must be a valid date before provided seed.

```javascript
let v = new Validator({valid:'2019-02-28'}, {valid:'required|dateBeforeToday:2,months'});
```

**dateFormat:format**  
The field under validation must match the given date format.

Note: use array of rules style declaration to deal with colon (:) in time formats.

```javascript
new Validator(
  { dob: '' },
  { dob: 'required|dateFormat:YYYY-MM-DD' },
);
```  

Check https://momentjs.com/docs/ for supported formats

**dateiso**  
<sub>Added in: v3.6</sub>  
The field under validation must be a valid iso date.

**datetime**  
<sub>Added in: v3.6</sub>  
The field under validation must match YYYY-MM-DD HH:mm:ss format.

**decimal**  
The field under validation must be a decimal value.

**digits:length**  
The field under validation must be numeric and must have an exact length.

**digitsBetween:min,max**  
The field under validation must have a length between provided min and max values.

**domain**  
The field under validation must a qualified domain.

**dimensions:seed**  
<sub>Added in: v3.7</sub>  
The image under validation must meet the dimension constraints as specified by in seed.

```js
new Validator(
  req.body,
  { file: 'dimensions:minWidth=50,minHeight=50' },
);

const matched = await v.check();

assert.equal(matched, false);
```

Note: image mimes validation is required before.

Available constraints are: minWidth, maxWidth, minHeight, maxHeight, width, height.

**email**  
The field under validation must be formatted as an e-mail address.

**equals**  
The field under validation must be equal to given value.

**gt:another_field**  
<sub>Added in: v3.4</sub>  
The field under validation must be greater then another field value. This rule is for Numbers comparision.

**gte:another_field**  
<sub>Added in: v3.4</sub>  
The field under validation must be greater or equals to another field value. This rule is for Numbers comparision.

**hash:algo**  
The field under validation must be a valid hash as per provided seed.

```javascript
new Validator(
  {
    id: 'fd1baf48377a9f644f9af89abbee29f6'
  },
  {
    id: 'required|hash:md5'
  },
);
```

Supported algorithms: md4, md5, sha1, sha256, sha384, sha512, ripemd128, ripemd160, tiger128, tiger160, tiger192, crc32, crc32b.

**hex**  
The field under validation must be valid hex.

**hexColor**  
The field under validation must be valid hex color code.

**in:a,b...n**  
The field under validation must exist in the given list of values.

```javascript
new Validator(
  { status: '' },
  { status: 'required|in:active,inactive,blocked' },
);
```

**integer**  
The field under validation must be an integer.

**ip**  
The field under validation must be an IP address.

**iso8601**  
The field under validation must be valid Iso8601 date.

**json**  
The field under validation must be a valid JSON string.

**length:max**  
**length:max,min**  
<sub>Added in: v3.5</sub>  
The field under validation must be less then or equals to max seed provided in rule. In case of min,max seed, field under validation must be less or equals to max seed and less then min seed. Can only be used with strings|arrays or any other object that supports length (str.length) property.

**latLong**  
The field under validation must be a valid latitude-longitude coordinate.

**lengthBetween:min,max**  
The field under validation value length must be between provided values.

```javascript
let v = new Validator({age:''}, {age:'required|between:17,30'});
```

**lt:another_field**  
<sub>Added in: v3.4</sub>  
The field under validation must be less then another field value. This rule is for Numbers comparision.

**lte:another_field**  
<sub>Added in: v3.4</sub>  
The field under validation must be less or equals to another field value. This rule is for Numbers comparision.

**macAddress**  
The field under validation should be a valid Mac Address.

**max:seed**  
The field under validation must be less than given value.

```javascript
new Validator(
  { age: '' },
  { age: 'required|max:35' },
);
```

**maxLength:seed**  
The length of field under validation should be less than given value.

```javascript
new Validator(
  { username: '' },
  { username: 'required|max:10' },
);
```

**mime:seed**  
The file under validation must have a MIME type corresponding to one of the listed extensions.

```javascript
new Validator(
  req.body,
  { file: 'required|mime:jpg,png' },
);
```

**min**  
The field under validation must be greater than given value.

**minLength**  
The length of field under validation should be greater than given value.

**mongoId**  
The field under validation should be a valid MongoDB ID.

**notContains:seed**  
The field under validation may not contains provided seeds.

**notIn:seeds**  
The field under validation must not exist in the given list of values.

**nullable**  
The field under validation is required only is not left empty.

**numeric**  
The field under validation must be numeric.

**phoneNumber**  
The field under validation must be a valid phone number.

**regex**  
The field under validation must match the given regular expression.

Note: Currently regex rules break on using colon (:) or pipe delimiters. Use array of rules style declaration instead of string.

```javascript
new Validator(
  req.body,
  { username: ['required', 'regex:[a-z]'] },
  { password: 'required|same:confirm_password' },
);
```

**same**  
The given field must match the field under validation.

**size:max**  
**size:max,min**  
The file field under validation must have a file size matching the given maximum value or should be between size range.
Supported unit sufix: b(Bytes),kb/k(KilloBytes),mb/m(MegaBytes),gb/g(GigaBytes).

```javascript
// in below case, image file size should be under 4kb limit
new Validator({image:''}, {image:'required|size:4kb'});
```

```javascript
// in below case, image file size should be between 1kb - 4kb
new Validator({image:''}, {image:'required|size:4kb,1kb'});
```

```javascript
new Validator({video:''}, {video:'required|size:10mb'});
```

**sometimes**  
The field under validation is required if present.

**string**  
The field under validation must be string.

**url**  
The field under validation must be a valid URL.

**Post Rules**  
There is set of rules which can be used to validate constraints of whole input, rather than validity of singular fields.

```javascript
const v = new Validator(
  { name: '' },
  { '*': 'any:name,surname' },
);

v.check().then(function (matched) {
  console.log(matched);
  console.log(v.errors);
});
```

Post validator errors are returned in the `*` key. There is also possibility to add custom function as validator
with help of `addPostRule` method. Function will be called in context of validator object with input as parameter.

```javascript
const v = new Validator(
  { username: 'arnold', password: 'arnold123' },
  { username: 'required', password: 'required' },
);

v.addPostRule((provider) => {
  if (provider.inputs.password.indexOf(provider.inputs.username) >= 0) {
    provider.error('password', 'custom', 'Password cannot contain username');
  }
});
```

**any**  
Any of the fields must be present in input.

**all**  
All of the fields must be present in input.

### Typescript Support

Partial Support.