PropChecker

Minimalist JavaScript object validation library.

Installation

PropChecker is packaged on npm:

$ npm install propchecker 

Usage Example

var config = {
    foo: [PropChecker.isRequired, PropChecker.isString],
    nested: {
        bar: PropChecker.isNumber,
        arr: PropChecker.isArray,
        anotherArray: PropChecker.isArrayOf(PropChecker.isNumber)
    }
};

var obj = {
    foo: 'some string',
    nested: {
        bar: 123, 
        arr: ['element1', 'element2'],
        anotherArray: [1, 2, 3, 4]
    }
};

var errorHandler = function(errors) {
    console.log(errors);
};

PropChecker.validate(obj, config, errorHandler);

Available checkers

isRequired

Check the property value is not a null and not an undefined

isString

Check the property value is a string

isNumber

Check the property value is a number

isBoolean

Check the property value is a boolean

isArray

Check the property value is a number

isObject

Check the property value is an object

isDate

Check the property value is a date

isFunction

Check the property value is a function

isRegExp

Check the property value is a regexp

isError

Check the property value is a error

isArrayOf

Check the property value is an array with specific elements type. Type specified through any PropChecker validator. Basic example:

var config = {
    arrayWithString: PropChecker.isArrayOf(PropChecker.isString),
    arrayWithArrayWithNumbers: PropChecker.isArrayOf(PropChecker.isArrayOf(PropChecker.isNumber))
};

var obj = {
    arrayWithString: ['some string', 'another string'],
    arrayWithArrayWithNumbers: [[1], [2, 3], [4, 5]]
};

PropChecker.validate(obj, config);

isEqual

Check the property value is equal to primitive, using strict equality operator inside. Basic example:

var config = {
    age: PropChecker.isEqual(18)
};

var obj = {
    age: 18
};

PropChecker.validate(obj, config);

isInherits

Check the property value to inherits another class. Basic example:

class BaseClass {}
class AnotherOne extends BaseClass {}

var config = {
    some: PropChecker.isInherits(BaseClass)
};

var obj = {
    some: AnotherOne
};

PropChecker.validate(obj, config);

Not enough?

You can define your own PropCheck validator. Type checker function should return null, when the value is valid, or an error instance, when the value is invalid. Basic example:

var myValidator = new PropChecker(function(propName, propValue) {
    if (propValue > 10) {
        return new TypeError(propName + ' is invalid'); 
    }
    
    return null;
});

var config = {
    age: myValidator
};

var obj = {
    age: 9
};

PropChecker.validate(obj, config);

License

MIT