https://github.com/vidursatija/express-joi-models
A middleware for validating express inputs using Joi schemas using classes
https://github.com/vidursatija/express-joi-models
Last synced: 7 months ago
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A middleware for validating express inputs using Joi schemas using classes
- Host: GitHub
- URL: https://github.com/vidursatija/express-joi-models
- Owner: vidursatija
- License: mit
- Created: 2022-05-21T10:00:10.000Z (over 3 years ago)
- Default Branch: master
- Last Pushed: 2022-05-27T16:04:54.000Z (over 3 years ago)
- Last Synced: 2025-03-18T16:58:04.793Z (7 months ago)
- Language: JavaScript
- Size: 14.6 KB
- Stars: 0
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- License: LICENSE
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README
# express-joi-model
[](https://www.npmjs.com/package/express-joi-model)
[](https://www.npmjs.com/package/express-joi-model)
A middleware for validating express inputs using Joi schemas using classes. Features include:
* Classes for validating input and output
* Replaces the incoming `req.body`, `req.query`, etc and with the validated result object with specified class
* Retains the original `req.body` inside a new property named `req.original-body`.
## Install
You need to install `joi` with this module since it relies on it in
`peerDependencies`.
```
npm i express-joi-model joi --save
```
## Example
A JavaScript example can be found in the `example/` folder of this repository.
## Usage (JavaScript)
```js
const express = require('express')
const { BaseModel, putValidationMiddleware } = require('express-joi-model')
const Joi = require('joi')
const app = express()
class RequestModel extends BaseModel {
static get __schema() {
return {
a: Joi.number(),
b: Joi.string()
}
}
}
app.use(express.json())
app.post('/', putValidationMiddleware({ body: RequestModel }), function (req, res) {
console.log(req.body)
return res.json({ res: true })
})
app.listen(8080)
```
## API
The library exports 3 variables - `ValidationError`, `BaseModel`, `putValidationMiddleware`.
1. `ValidationError` - the error thrown when validation of the object fails
2. `BaseModel` - the base class to inherit from when making your own model.
3. `putValidationMiddleware` - the function to generate the middleware using a config.
### ValidationError
```js
class ValidationError extends Error
```
It contains the error string
### BaseModel
```js
class BaseModel extends Object
```
The BaseModel class is to be used to create your own models. The class must have a *static* `__schema` property that must be overriden and must return an `Object` contains the appropriate keys and apt `Joi` values.
Eg:
```js
class RequestModel extends BaseModel {
static get __schema() {
return {
res: Joi.boolean(),
}
}
}
const resObj = RequestModel({res: true}) // VALID
const resObj2 = RequestModel({res: "123"}) // INVALID: throws ValidationError
```
This ensures that the object passed to `RequestModel` class will follow the schema.
### putValidationMiddleware
```js
function putValidationMiddleware(cfg): function baseModelValidation(req, res, next)
```
Config can only have 4 keys that define what part of request has to be validated. The values have to be **classes** inherited from *BaseModel*:
1. `body` -> validates `req.body` and stores the validated object in `req.body` and the original body in `req.original_body`
2. `query` -> validates `req.query` and stores the validated object in `req.query` and the original body in `req.query`
3. `params` -> validates `req.params` and stores the validated object in `req.params` and the original body in `req.original_params`
4. `response` -> validates the response post return. The response has to be a json object. Returns 500 if response schema doesn't validate.
The input validations return 400 if the input isn't valid.
Eg:
```js
app.post('/correct', putValidationMiddleware({ body: RequestModel, response: ResponseModel }), function (req, res) {
console.log(req.body)
return res.json({ res: true })
})
```
## Future TODO
- Better error handling + modification capabilities
- Better configurabilty for Joi in request and response