Jevalide

Tired of writing complex validation logic? Jevalide is your solution for clean, maintainable form validation that just works.

Why Choose Jevalide?

Write your validation rules once and use them everywhere. Jevalide is a lightweight validation library that works seamlessly in both browser and Node.js environments. Whether you're building a complex web application or a simple Node.js service, Jevalide has got you covered.

No complexity - just simple, powerful validation when you need it.

Installation

Using npm:

npm install jevalide

Quick Start

Jevalide simplifies validation with minimal setup. Here's how it works:

Simple Validation with validate

The Jevalide.validate method is perfect for quickly validating data without additional configuration:

// Import Jevalide
import { Jevalide } from 'jevalide';

const data = {
  email: '[email protected]',
  password: '12345'
};

const rules = {
  email: ['required', 'email'],
  password: ['required', 'minlength:8']
};

const validator = Jevalide.validate(data, rules);

if (validator.isValid()) {
  console.log('Validation passed!');
} else {
  console.log(validator.getErrors());
  // Output: { password: 'Password must be at least 8 characters' }
}

Customize with init

The Jevalide.init method allows you to set up global configurations, such as custom rules, messages, and locales:

// Initialize with custom options
const validator = Jevalide.init({
  rules: {
    customRule: (value) => ({
      passes: /^[a-zA-Z]+$/.test(value),
      value
    })
  },
  messages: {
    required: 'This field is required',
    email: 'Please enter a valid email',
    customRule: 'Only letters are allowed'
  },
  local: 'en'
});

Validate Forms

Effortlessly validate entire forms:

const form = validator.form({
  email: ['required', 'email'],
  password: ['required', 'minlength:8']
}, {
  email: '[email protected]',
  password: '12345'
});

if (form.passes()) {
  console.log('All good!');
} else {
  console.log(form.getErrors());
  // Output: { password: 'Password must be at least 8 characters' }
}

Input Validation

Handle single input validation:

const emailValidator = validator.input({
  name: 'email',
  rules: ['required', 'email']
});

emailValidator.setValue('invalid-email');
console.log(emailValidator.getError());
// Output: 'Please enter a valid email'

Custom Rules Made Easy

Add your own validation logic:

validator.rule('username', (value) => ({
  passes: /^[a-zA-Z0-9_]+$/.test(value),
  value
}), 'Username can only contain letters, numbers, and underscores');

Support for Multiple Languages

Customize messages for different locales:

validator.translate('fr', {
  required: 'Ce champ est requis',
  email: 'Veuillez entrer une adresse email valide'
});

validator.setLocale('fr');

Usage in Different Environments

Node.js

For CommonJS environments:

const { Jevalide } = require('jevalide');

Browser

For browser environments, simply include Jevalide in your HTML:

<script>
  const validator = Jevalide.init({
    messages: {
      required: 'This field is required',
      email: 'Please enter a valid email'
    }
  });

  document.querySelector('form').addEventListener('submit', (e) => {
    e.preventDefault();

    const form = validator.form({
      email: ['required', 'email'],
      password: ['required', 'minlength:8']
    }, {
      email: document.querySelector('input[name="email"]').value,
      password: document.querySelector('input[name="password"]').value
    });

    if (form.passes()) {
      // Submit the form
    } else {
      console.log(form.getErrors());
    }
  });
</script>

Some Built-In Rules

| Name | Description | | ---------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | required | Ensures the field is not empty. Works with strings, arrays, objects, numbers, booleans, etc. Example: required | | nullable | Always passes; effectively makes a field optional. Example: nullable | | in:x,y | Checks if the input value is among the comma-separated list (x, y, etc.). Example: required\|in:admin,user,guest | | size:x | If it’s a file, checks file size. Otherwise checks the exact length for strings. Example: required\|size:5 | | boolean | Checks if the input is a boolean or a “boolean-like” string ("true","false","yes","no","1","0"). Example: required\|boolean | | between:x,y | General “range” check for numbers, strings, dates, or file size. Ensures the value is between x and y. Example: required\|between:18,99 | | regex:pattern | Validates that the input matches the given regular expression. Example: regex:^[0-9]{3}-[0-9]{4}$ | | only:string / only:digit | Restricts the input to either letters only (for "string") or strictly digits (for "digit"). Example: only:string or only:digit | | digit:x | Checks if the input is purely digits and exactly x digits long. Example: digit:5 | | maxDigit:x | Checks if the input is purely digits and at most x digits long. Example: maxDigit:10 | | minDigit:x | Checks if the input is purely digits and at least x digits long. Example: minDigit:3 | | equal:value | Ensures the input is strictly equal (===) to the given value. Example: equal:secret | | same:fieldValue | Ensures the input loosely equals (==) another field’s value (useful for confirmations). Example: same:password | | object | Checks if the input is a valid object (not null or an array). Optionally enforce required keys. Example: required\|object:name,age | | json | Checks if the input is valid JSON. Optionally ensure required keys or indexes. Example: json:key1,key2 | | array | Checks if the input is an array; optionally validate certain indexes. Example: array:0,1 | | email | Validates if the input is a valid email address. Example: required\|email | | minlength:x | Ensures the string length is at least x. Example: required\|minlength:8 | | maxlength:x | Ensures the string length does not exceed x. Example: required\|maxlength:10 | | string | Checks if the value is a string. Example: required\|string | | url | Checks if the string is a valid URL. Example: required\|url | | startWithUpper | Ensures the string starts with an uppercase letter. Example: startWithUpper | | startWithLower | Ensures the string starts with a lowercase letter. Example: startWithLower | | startWith:x,y | Checks if the string starts with any of the given prefixes (x, y, etc.). Example: startWith:pre1,pre2 | | endWith:x,y | Checks if the string ends with any of the given suffixes (x, y, etc.). Example: endWith:suf1,suf2 | | contains:x,y | Checks if the string contains all of the listed substrings (x, y, etc.). Example: contains:foo,bar | | length:x | Validates that the string length is exactly x. Example: length:9 | | password | Basic password complexity: length ≥ 8, uppercase, lowercase, number, special char. Example: required\|password | | startWithString | Ensures the input does not start with a digit. Example: startWithString | | endWithString | Ensures the input does not end with a digit. Example: endWithString | | hasLetter | Ensures the string contains at least one letter. Example: hasLetter | | excludes:x,y | Ensures none of the characters/strings listed (x, y) appear in the input. Example: excludes:@,/,# | | upper | Ensures the string is entirely uppercase. Example: upper | | lower | Ensures the string is entirely lowercase. Example: lower | | stringBetween:min,max | Ensures the string length is between min and max. Example: stringBetween:2,5 | | date | Checks if the input is a valid date using Day.js. Returns true if valid, false otherwise. Example: required\|date | | before:x | Ensures the input date is before the date x. You can use "now" for the current date/time. Example: required\|before:2020-01-01, required\|before:now | | after:x | Ensures the input date is after the date x. You can use "now" for the current date/time. Example: required\|after:2020-01-01, required\|after:now | | dateBetween:x,y | Checks if the input date lies between the two dates x and y. You can use "now" in place of either bound. Example: required\|dateBetween:2020-01-01,now | | time | Checks if the input is a valid 24-hour time string (e.g., "HH:mm:ss"). If missing seconds, it automatically appends ":00" until the format is complete. Example: required\|time | | min:x | Checks the input value or character length against the minimum x. For numbers, ensures value >= x. For files, checks file size. Example: required\|min:2 | | max:x | Checks the input value or character length against the maximum x. For numbers, ensures value <= x. For files, checks file size. Example: required\|max:20 | | integer / int | Ensures the input is an integer. Example: required\|integer, required\|int | | number / numeric | Validates that the input can be parsed as a numeric value (not an object/boolean). Example: required\|number | | modulo:x / mod:x | Checks if the number is divisible by x. Example: required\|modulo:2, required\|mod:2 | | lessThan:x / lthan:x | Ensures the input value is strictly less than x. Example: required\|lessThan:10, required\|lthan:10 | | greaterThan:x / gthan:x | Ensures the input value is strictly greater than x. Example: required\|greaterThan:5, required\|gthan:5 | | numberBetween:x,y | Checks if the numeric input lies between x and y (inclusive). Example: required\|numberBetween:1,10 | | phone | Validates if the input is a phone number (for example, using a custom phone rule). Example: required\|phone | | file | Checks if the input is a File, Blob, FileList, or an array of such items. Example: required\|file | | maxFileSize:x | Ensures the file size is at most x (e.g. 1MB). Example: required\|maxFileSize:2MB | | minFileSize:x | Ensures the file size is at least x (e.g. 1MB). Example: required\|minFileSize:500KB | | fileBetween:x,y | Checks that the file size is between x and y. Example: required\|fileBetween:1MB,5MB | | mimes:x,y | Validates the file’s MIME type/extension. Supports wildcards (*.jpg), type groups (image/*), or specific extensions. Example: required\|mimes:*.pdf,image/* |

With Jevalide, validation is no longer a hassle. Customize once, reuse everywhere, and keep your validation logic clean and maintainable.