http-error-handling

Handling HTTP errors for your Express application easily.

Install

This is a Node.js module available through the
npm registry. Installation is done using the
npm install command:

``console
npm install http-error-handling
`

Features

- ErrorObject
- HttpError
- RequestValidator

Examples

$3

`js
var { HttpError } = require("http-error-handling")
var express = require("express")
var app = express()
// in the beginning of your app (important)
app.use(HttpError.initializer)
// your app routes or other middlewares
//sample APIs
app.get("/400", (req, res, next) => {
return HttpError.BadRequest()
})
app.get("/500", (req, res, next) => {
return HttpError.InternalServerError("something went wrong")
})
app.get("/custom", (req, res, next) => {
const customError = {
statusCode: 502,
message: "custom message",
errorKey: "custom_error", // optional parameter
description: "description", // optional parameter
help: "https://domain.example/integration/fixes/custom-api", // optional parameter
invalidParams: [
{
message: "invalid value",
location: "body", // optional parameter
param: "email",
},
//you can add more objects
], // optional parameter
}
return HttpError.customError(errorObject)
})

//in the end of your app (important)
app.use(HttpError.handler)
`

$3

`js
import { ErrorsAttrs, HttpError } from "http-error-handling"
import express, { NextFunction, Request, Response } from "express"
let app = express()
// in the beginning of your app (important)
app.use(HttpError.initializer)
// your app routes or other middlewares
//sample APIs
app.get("/400", (req: Request, res: Response, next: NextFunction) => {
return HttpError.BadRequest("invalid request data")
})
app.get("/500", (req: Request, res: Response, next: NextFunction) => {
return HttpError.InternalServerError()
})
app.get("/custom", (req: Request, res: Response, next: NextFunction) => {
const custom: ErrorsAttrs = {
statusCode: 502,
message: "custom message",
errorKey: "custom_error", // optional parameter
description: "description", // optional parameter
help: "https://domain.example/integration/fixes/custom-api", // optional parameter
invalidParams: [
{
message: "invalid value",
location: "body", // optional parameter
param: "string",
},
//you can add more objects
], // optional parameter
}
return HttpError.customError(errorObject)
})

//in the end of your app (important)
app.use(HttpError.handler)
`

ErrorObject

- statusCode: the status code of the error. required
- message: the error message. required
- description: the error description. optional
- help: the error url that can help the client to fix the api issue e.g
() optional
- invalidParams: the errors of request in case you need to validate the
request data. optional

- message: the error message. required
- param: the error parameter name e.g (email, password, name, etc). optional
- location: the location of parameter key. required

- errorKey: the error key and the main purpose we can use it for localization part
and in this case we will have a generic errors we can catch any error message
by key for example: we can store local.en.json and local.en.json includes

`json
{ "bad_request": "invalid user request data" }
`

and local.ar.json includes

`json
{ "bad_request": "بايانات غير صحيحة" }
`

and the both files located in the
frontend so by using the response errorKey we can localize the error message
easily. optional

HttpError

$3

it's a middleware should be used in the top of your app or at lest before your
routes that include HttpError

`js
// in the beginning of your app (important)
app.use(HttpError.initializer)
// OR
app.use((req, res, next) => {
HttpError.initializer(req, res, next)
})
`

$3

it's a middleware and it will handle all the errors returned by
HttpError functions and it will send it back to the client but if the error
not belong ot the lib it will pass it using next fun

`js
// in the end of your app (important)
app.use(HttpError.handler)
// OR
app.use((err, req, res, next) => {
HttpError.handler(err, req, res, next)
})
`

$3

it's a helper function can help you to create your custom error.

$3

- they are helper functions allow you to send sepecific error to the client

- attrs error object to customize your error response optional
- message: the error message. required
- errorKey: the error key. optional
- help: the error help location/url. optional
- description: the error description optional
- invalidParams: the request parameters errors optional

| status code | function name |
| ----------- | ----------------------------- |
| 400 | BadRequest |
| 401 | Unauthorized |
| 402 | PaymentRequired |
| 403 | Forbidden |
| 404 | NotFound |
| 405 | MethodNotAllowed |
| 406 | NotAcceptable |
| 407 | ProxyAuthenticationRequired |
| 408 | RequestTimeout |
| 409 | Conflict |
| 410 | Gone |
| 411 | LengthRequired |
| 412 | PreconditionFailed |
| 413 | PayloadTooLarge |
| 414 | URITooLong |
| 415 | UnsupportedMediaType |
| 416 | RangeNotSatisfiable |
| 417 | ExpectationFailed |
| 418 | ImATeapot |
| 421 | MisdirectedRequest |
| 422 | UnprocessableEntity |
| 423 | Locked |
| 424 | FailedDependency |
| 425 | TooEarly |
| 426 | UpgradeRequired |
| 428 | PreconditionRequired |
| 429 | TooManyRequests |
| 431 | RequestHeaderFieldsTooLarge |
| 451 | UnavailableForLegalReasons |
| 500 | InternalServerError |
| 501 | NotImplemented |
| 502 | BadGateway |
| 503 | ServiceUnavailable |
| 504 | GatewayTimeout |
| 505 | HTTPVersionNotSupported |
| 506 | VariantAlsoNegotiates |
| 507 | InsufficientStorage |
| 508 | LoopDetected |
| 509 | BandwidthLimitExceeded |
| 510 | NotExtended |
| 511 | NetworkAuthenticationRequired |

---

RequestValidator

it's a middleware should be used after validating the request
body/parameter/query using express-validator library

`js
import { body } from "express-validator"
import { RequestValidator } from "http-error-handling"
import express, { NextFunction, Request, Response } from "express"
let app = express()
//sample API
app.get("/validate", body("email").isEmail(), RequestValidator, (req: Request, res: Response, next: NextFunction) => {
return res.send(req.body)
})
``

License

MIT