Request Guardian

request-guardian registers express-validator rules on an Express app. Rules come from your project's utils/validations/index.js. Failed validation returns 422. Unexpected errors while running validators return 400.

Installation

npm install request-guardian

yarn add request-guardian

This package depends on express-validator. Use it with Express.

Usage

Call validate(app) after body parsers such as express.json(), and before you define route handlers. validate attaches middleware when it runs, so calling it after app.post(...) can skip validation.

const express = require('express');
const validate = require('request-guardian');

const app = express();

app.use(express.json());
validate(app);

app.post('/users', (req, res) => {
    // request already passed validation for this path
});

Put validation rules in utils/validations/index.js at the application root (the process working directory), not inside node_modules. Keys must match the Express paths you register.

Each path can be:

• An array of validation chains: applied to every method (app.use).
• An object keyed by HTTP method: different rules for GET, POST, and other methods on the same path.

Supported method keys (case-insensitive): all, get, post, put, delete, patch, options, head. Unknown keys are ignored.

Method-specific rules

Use this when the same path needs different rules per method:

// utils/validations/index.js
const { body, query } = require('express-validator');

module.exports = {
    '/api/authentication/signup': {
        GET: [
            query('page').optional().isInt({ min: 1 }),
        ],
        POST: [
            body('email').isEmail(),
            body('password').isLength({ min: 8 }),
        ],
    },
};

all applies to every method on that path, the same as a bare array:

module.exports = {
    '/api/reports': {
        all: [
            query('from').optional().isISO8601(),
        ],
    },
};

Same rules for every method

const { body } = require('express-validator');

module.exports = {
    '/api/users': [
        body('name').notEmpty(),
    ],
};

If a path is not listed, no validation middleware is attached for it. If utils/validations/index.js is missing, validate() logs Validations rules not found at utils/validations/index.js and registers nothing.

Responses

Validation failure:

{
    "data": [],
    "status": "VALIDATION_ERROR",
    "message": "Invalid Data, Validation Failed."
}

data is express-validator's errors.array().

Unexpected error while running validators:

{
    "data": "error message",
    "status": "BAD_REQUEST",
    "message": "error message"
}

HTTP status codes: 422 for validation errors, 400 for other failures in the validator.