extensible-validator
Typescript-friendly and extensible object and value validation.
Also, unlike like other libraries where validate throws an error, I just return an array of errors, which could be empty. Throwing an error in the case of bad input from a function which exists to consider the case of bad input is ugly as hell.
I also separate validating and "casting" the input to a desired output format, because they're two separate operations.
Usage
Install:
$ npm install --save extensible-validator
Import, then define and use a schema:
import { object, string, number } from 'extensible-validator';
let validator = object.keys({
name: string.required(),
age: number.integer(),
});
let person = { name: 'Bob', age: 32 };
console.log(validator.validate(person));
// []
let notAPerson = { age: "what's my age again?" };
console.log(validator.validate(notAPerson));
// [{message: 'required', path: 'name'}, {message: 'must be a number', path: 'age'}]If you want to extend the validator functionality, you can either add tests to existing types:
const objectId = string.addTest(value => ObjectId.isValid(value));
const person = object.keys({
_id: objectId.required(),
name: string.required(),
});Or you can define a new schema class:
class ObjectIdSchema extends Schema<ObjectId> {
constructor() {
super({ type: 'must be an ObjectId' }, value => ObjectId.isValid(value));
}
cast(value: any) {
return value instanceof ObjectId ? value : new ObjectId(value);
}
}The latter gives you more control, and the ability to override the type test and the cast method.
TODO