A wrapper around validate.js to facilitate easy function parameter validation in JavaScript.
npm install @maynoothuniversity/validate-paramsA wrapper around validate.js to facilitate easy
function parameter validation in JavaScript.
validate.js is designed to validate web forms. HTML form data is
fundamentally a collection of name-value pairs, so it makes sense that the
validation functions provided by validate.js expect both the data to be
validated, and the constraints to be applied to that data to be specified as
collections of name-value pairs (JavaScript objects).
Function parameters are not name-value pairs, they are lists of values. Hence,
the validation functions provided by this module expect both the data to be
validated, and the constraints to be applied to that data to be specified as
lists.
Internally, the module converts the passed parameter and constraint lists to
collections of name-value pairs which it then validates with validate.js.
As well as translating between lists and name-value pairs, the module also
provides a number of other additional features which focus on parameter
validation, including the specification of default values, support for data
coercion, improved support for nested constraints, and a number of additional
validators.
Install the module and its dependencies:
``
npm install '@maynoothuniversity/validate-params' --save
Load the module:
`
var validateParam = require('@maynoothuniversity/validate-params');
`
`
// passes through the return value from validate.js
var errors = validateParams(parameterList, constraintList, [options]);
or
`
// returns a validateParams.Result object
var result = validateParams.validate(parameterList, constraintList, [options]);
`
// throws a validateParams.ValidationError if validation fails
validateParams.assert(parameterList, constraintList, [options]);
The parameterList can be an array, or, JavaScript's special arguments
variable.
The constraintList is an array of object literals, each defining one or morevalidate.js compatible constraints.
The optional options parameter should be an object literal, and can be usedvalidate.js
to specify options that alter both the behaviour of the validation functions
provided by this module, and the validation functions from used to
perform the actual validations.
`
// An implementation of the Factorial function
// The first argument must be present, an integer, and >= 0
function fact(n){
// validate the parameter
validateParams.assert(
arguments,
[{
presence: true,
numericality: {
onlyInteger: true,
greaterThanOrEqualTo: 0
}
}
]); // will throw a validateParams.ValidationError on invalid params
// do the calculation
var ans = 1;
while(n > 0){
ans *= n;
n--;
}
// return the result
return ans;
}
var x = fact(4); // x=24
var y = fact('4'); // x=24
var z = fact('stuff'); // throws validateParams.ValidationError
``
* API Documentation for validateParams.js: bbusschots-mu.github.io/...
* API Documentation for validate.js: validatejs.org/...