Sontaran


Sontaran is a javascript validator library. It has a lot validation options out of the box and all validators are extendable with custom validation functions.

Some key features

- Completely written in Typescript
- CommonJS build for Node JS
- Tree shakable ES build
- Fluid, chainable api
- Support for async validators with the validateAsync method

Installation

Sontaran can be installed using npm.

``bash
npm install --save sontaran
`

For the complete code including all tests the repo can be cloned.

`bash
git clone https://github.com/Barry127/sontaran.git
cd sontaran
npm run test
`

Getting Started

The object().schema() function takes a schema of Sontaran validators as an argument.

In this example:

username

- Must be a string
- Cannot be only empty characters (spaces, tabs, return, ...)
- Must have a length between 3 and 10 characters
- Must match the given RegExp (only contain alphanumeric characters and dash, underscore)

email

- Must be a valid email

password

- Must be a string
- Must have a length of at least 8 characters

`javascript
import { object, string, email } from 'sontaran';

const schema = object().schema({
username: string()
.notEmpty()
.between(3, 10)
.match(/^[a-zA-Z0-9_\-]*$/),
email: email(),
password: string().min(8)
});

// Valid schema (return true)
schema.validate({
username: 'sontaran',
email: 'email@domain.com',
password: 'mySuperSecretPassword'
}); /** => {
valid: true,
value: {
username: 'sontaran',
email: 'email@domain.com',
password: 'mySuperSecretPassword
}
}*/

// invalid usernames
let a = 123; // => not a string
let b = ' \t\r'; // => Empty characters
let c = 'aa'; // => too short
let d = 'Hello-World'; // => too long
let e = 'B@dInput'; // => invalid character
`

Sontarans custom can take any ValidatorFunction function as argument to validate and / or transform a value.

`javascript
import { string, ValidationError } from 'sontaran';

// value cannot be root and is transformed to lowercase
const myCustomValidator = (value) => {
if (value.toLocaleLowercase() === 'root') {
throw new ValidationError('root is not allowed');
}

return value.toLocaleLowercase();
};

const schema = string().custom(myCustomValidator);

// valid result transformed to lowercase
const result = schema.label('username').validate('Admin');
/* => {
valid: true,
value: 'admin'
}*/

// invalid result
const result = schema.label('username').validate('Root');
/* => {
valid: false,
value: 'Root',
errors: [{
field: 'username',
message: 'root is not allowed',
type: 'root is not allowed'
}]
}
*/
``