Validating Query Parameters Using Express Validator

Here is how to validate query parameters using express validator.

To check for variables in query params, i.e., req.query, use query([fields, message]). Same as check([fields, message]), but only checking req.query.

Example:

Installing express-validator

npm install --save express-validator

Importing query

const { query } = require('express-validator/check');

Using query

router.post('/add-product', 
                isAuth, 
                [
                    query('title')
                        .isString().withMessage('Only letters and digits allowed in title.')
                        .trim()
                        .isLength({min: 3}).withMessage('Title too short. Enter a longer title!'),
                    query('price', 'Enter a valid price.')
                        .isFloat(),
                    query('description')
                        .trim()
                        .isLength({min: 30, max: 600}).withMessage('Description must be of minimum 30 and maximum 600 characters!'),
                ],
                adminController.postAddProduct);

See official documentation here: https://express-validator.github.io/docs/check-api.html

Comments

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