# http-errors

[![NPM Version](https://badgen.net/npm/v/http-errors)](https://npmjs.org/package/http-errors) [![NPM Downloads](https://badgen.net/npm/dm/http-errors)](https://nodejs.org/en/download) [![Node.js Version](https://badgen.net/npm/node/http-errors)](https://nodejs.org/en/download) [![Build Status](https://badgen.net/travis/jshttp/http-errors/master)](https://travis-ci.org/jshttp/http-errors) [![Test Coverage](https://badgen.net/coveralls/c/github/jshttp/http-errors/master)](https://coveralls.io/r/jshttp/http-errors?branch=master)

Create HTTP errors for Express, Koa, Connect, etc. with ease.

## Install

This is a [Node.js](https://nodejs.org/en/) module available through the [npm registry](https://www.npmjs.com/). Installation is done using the [`npm install` command](https://docs.npmjs.com/getting-started/installing-npm-packages-locally):

```bash
$ npm install http-errors
```

## Example

```js
var createError = require('http-errors')
var express = require('express')
var app = express()

app.use(function (req, res, next) {
  if (!req.user) return next(createError(401, 'Please login to view this page.'))
  next()
})
```

## API

This is the current API, currently extracted from Koa and subject to change.

### Error Properties

* `expose` - can be used to signal if `message` should be sent to the client, defaulting to `false` when `status` >= 500
* `headers` - can be an object of header names to values to be sent to the client, defaulting to `undefined`. When defined, the key names should all be lower-cased
* `message` - the traditional error message, which should be kept short and all single line
* `status` - the status code of the error, mirroring `statusCode` for general compatibility
* `statusCode` - the status code of the error, defaulting to `500`

### createError(\[status], \[message], \[properties])

Create a new error object with the given message `msg`. The error object inherits from `createError.HttpError`.

```js
var err = createError(404, 'This video does not exist!')
```

* `status: 500` - the status code as a number
* `message` - the message of the error, defaulting to node's text for that status code.
* `properties` - custom properties to attach to the object

### createError(\[status], \[error], \[properties])

Extend the given `error` object with `createError.HttpError` properties. This will not alter the inheritance of the given `error` object, and the modified `error` object is the return value.

```js
fs.readFile('foo.txt', function (err, buf) {
  if (err) {
    if (err.code === 'ENOENT') {
      var httpError = createError(404, err, { expose: false })
    } else {
      var httpError = createError(500, err)
    }
  }
})
```

* `status` - the status code as a number
* `error` - the error object to extend
* `properties` - custom properties to attach to the object

### new createError\[code || name]\(\[msg]))

Create a new error object with the given message `msg`. The error object inherits from `createError.HttpError`.

```js
var err = new createError.NotFound()
```

* `code` - the status code as a number
* `name` - the name of the error as a "bumpy case", i.e. `NotFound` or `InternalServerError`.

#### List of all constructors

| Status Code | Constructor 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         | UnorderedCollection           |
| 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 |

## License

[MIT](https://github.com/bgoonz/Learning-Redux/blob/master/repos/examples/real-world/node_modules/http-errors/LICENSE/README.md)


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