Description

node.js module for validating (primarily) function parameters.

DESIGN:

This module provides is the same as Dmitry Sheiko's bycontract module, with the feature extensions described below. I tried contracting Dmitry to get his direction on the best way to extend his module, but he hasn't replied to me. Not knowing if I will have to repeat this extension work, I went with strategy that I can do most quickly and easily (but not necessarily best long-term)-- I just made this new module that loads the bycontract module and adds to it.

Installation

npm install @admc.com/bycontract-plus

Usage

Developers will usually want to import/require the 'validate' and 'is' objects. The first for performing validations, and the second to add custom validator types.

ES6 module environments:

import { validate, is } from "@admc.com/bycontract-plus";

ES5 CommonJS environments:

const { validate, is } = require("@admc.com/bycontract-plus");

Validate function calls are the same as for bycontract other than...

Allow more than two arguments elements:

validate(arguments, ["string", "int"], false);

In case of validation failure, use the specified Error message.

validate(var, "string", "%ith element in issue list not a string", i);

In particular, the run "[]" no longer means "any" Array, it means precisely [], a 0-length array. To get the original bycontract behavior to test for any Array, use:

validate(var, "", false);
validate(arguments, [""], false);

Enhancements over bycontract (without "-plus") module

1. The original 'validate' function requires 2 and only 2 parameters. I support some optional extra params.
2. For validate calls where contract parameter (2nd) is an Array, I enforce that the number of value elements doesn't exceed that of the specified contract.
3. Test element count enforcement (previous item) is not done if 3rd parameter to validate call given as fase.
4. If the first non-boolean validate parameter after #2 is a string, then it is a message to be used in validation Errors, overriding the default.
5. The message for previous feature can use util.format % placeholders, with format varargs parameters being all remaining parameters.

I added the following validator types. I've added description for the ones where the type-name isn't intuitive.

• int
• date
• posint
• nonnegint Non-negative integer
• posnum
• nonnegnum Non-negative number
• isotimestr Allows optional Z, +nn:nn, -nn:nn time zone suffix
• isotimestr_s No time zone suffix
• plainobject
• strictdatestr Format yyyy-mm-dd, where the segments must be 4 char + 2 char + 2 char