yup schemas for express, mongoose

This package for project using: express, mongoose and yup.

How to install

$ npm install yup-schemas

What can yup schemas do?

For example, with reqQuery, you can easily implement features such as:

- params valdiation
- pagination
- limit fields
- sorting
- filtering

Introduction

This package exports 2 middlewares and 4 pre-build schemas:

``javascript
const {
validateRequest, // middleware
requiredFields, // middleware
//
reqParams, // yup schema to validate req.params
reqQuery, // yup schema to parse req.query
objectId, // use to check if string is valid mongodb objectid
objectIdArray, // use to validate if an array only contains objectid
} = require('yups-schema');
`

Detail

- validateRequest: accept yup schema as input and validate req.body. Return 400 error if validation failed.

- requiredFields: accepts a string or multiple strings and check if they are defined. Return 400 error if the required fields are not defined.

You can use these pre-build yup schemas to:

- reqParams: check if req.params.id is a valid objectId
- reqQuery: validate and parse req.query
- objectId: check if a field is a valid objectId
- objectIdArray: check if a field is array of objectIds

How to use ?

To use yup-schemas, you first need to install yup:

$ npm install yup

Then, you need to define your schema using yup and yup-schemas

`javascript
// using schema to quickly validate
const yup = require('yup');
const { objectId, reqQuery } = require('yup-schemas');

const productSchema = yup.object({
body: yup.object({
// write your code to validate req.body here
}),

// validate req.params
params: reqParams, // check if req.params.id is a valid mongodb ObjectId

// validate and parse req.query
query: reqQuery,
});
`

Finally, import schema and pass it to route handler like this example:

`javascript
// Using middleware to validate
const express = require('express');
const { requiredFields, validateRequest } = require('yup-schemas');
const router = express();

router.use(
'/',
requiredField('name', 'price'), // make sure name and price are required
validateRequest(productSchema), // validate req.body, req.params and req.query using defined schema
yourHandlerHere,
);
`

Here are some examples how reqQuery parse your query

There are 2 types of queries: special queries & normal queries

How special queries being parsed:

Special queries includes: page, itemsPerPage, sort, fields, skip, limit

| endpoint | req.query |
| ---------------------------------- | --------------------------------------------- |
| /products?page=1 | { page : 1, filter : {} } |
| /products?itemsPerPage=1 | { itemsPerPage : 1, filter : {} } |
| /products?fields=price,name,status | { fields:"price name status", filter : {} } |
| /products?sort=price,-name,status | { sort:"price -name status", filter : {} } |
| /products?skip=1 | { skip : 1, filter : {} } |
| /products?limit=1 | { limit : 1, filter : {} } |

How other queries being parsed:

| endpoint | req.query |
| ----------------------------------------- | ----------------------------------------------------------------- |
| /products?price=24 | { filter : { price: '24' } } |
| /products?price=26,12 | { filter : { price: { $in: [ '26', '12' ] } } } |
| /products?price=15&status=active&price=14 | { filter : { price: { $in: [ '15', '14' ] }, status:"active"} } |
| /products?price[gt]=4 | { filter : { price: { $gt: 4 }} } |
| /products?price[gte]=4 | { filter : { price: { $gte: 4 }} } |
| /products?price[lt]=4 | { filter : { price: { $lt: 4 }} } |
| /products?price[lte]=4 | { filter : { price: { $lte: 4 }} } |

Example

Implement pagination, limit fields, sorting and filter using reqQuery.

`javascript
// productSchema.js
const reqQuery = require('yup-schemas');
const yup = require('yup');

const productSchema = yup.object({
body: yup.object({
// your product schema definition here
}),
query: reqQuery,
});
`

`javascript
// productRoutes.js
const express = require('express');
const router = express.Router();
const productSchema = require('./productSchema'); // import yup schema

// parse query and validate query before getAllProducts handler
router.get('/', validateRequest(productSchema), getAllProducts);
`

`javascript
// productControllers.js
const express = require('express');
const router = express.Router();
const productSchema = require('./productSchema'); // import yup schema
const Product = require('./productModel'); // import your mongoose model here

const getManyProducts = async (req, res, next) => {
const {
fields,
sort = '-createdAt', // new to old
page = 1,
itemsPerPage = 20,
filter,
} = req.query;

// 0. check how many result
const matchingResults = await Product.countDocuments(filter);
const totalPages = Math.ceil(matchingResults / itemsPerPage);

if (page > totalPages) {
return res.status(200).json({
status: 'success',
results: 0,
data: [],
});
}

// 1. create inital query but not await it
let query = Product.find(filter);

// 2. sorting
query = query.sort(sort);

// 3. limit fields
if (fields) {
query = query.select(fields);
}

// 4. pagination
const skip = (page - 1) * itemsPerPage;
const limit = itemsPerPage;

query = query.skip(skip).limit(limit);

// 5. finally await query
const ones = await query;

res
.status(200)
.json({ status: 'success', totalPages, results: ones.length, data: ones });
};
``

$3

This package only have 2 dependencies: yup & mongoose