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<img src="docs/media/Banner.svg" alt="Node Fetch"/> | |
<br> | |
<p>A light-weight module that brings <a href="https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API">Fetch API</a> to Node.js.</p> | |
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--- | |
**You might be looking for the [v2 docs](https://github.com/node-fetch/node-fetch/tree/2.x#readme)** | |
<!-- TOC --> | |
- [Motivation](#motivation) | |
- [Features](#features) | |
- [Difference from client-side fetch](#difference-from-client-side-fetch) | |
- [Installation](#installation) | |
- [Loading and configuring the module](#loading-and-configuring-the-module) | |
- [Upgrading](#upgrading) | |
- [Common Usage](#common-usage) | |
- [Plain text or HTML](#plain-text-or-html) | |
- [JSON](#json) | |
- [Simple Post](#simple-post) | |
- [Post with JSON](#post-with-json) | |
- [Post with form parameters](#post-with-form-parameters) | |
- [Handling exceptions](#handling-exceptions) | |
- [Handling client and server errors](#handling-client-and-server-errors) | |
- [Handling cookies](#handling-cookies) | |
- [Advanced Usage](#advanced-usage) | |
- [Streams](#streams) | |
- [Accessing Headers and other Metadata](#accessing-headers-and-other-metadata) | |
- [Extract Set-Cookie Header](#extract-set-cookie-header) | |
- [Post data using a file](#post-data-using-a-file) | |
- [Request cancellation with AbortSignal](#request-cancellation-with-abortsignal) | |
- [API](#api) | |
- [fetch(url[, options])](#fetchurl-options) | |
- [Options](#options) | |
- [Default Headers](#default-headers) | |
- [Custom Agent](#custom-agent) | |
- [Custom highWaterMark](#custom-highwatermark) | |
- [Insecure HTTP Parser](#insecure-http-parser) | |
- [Class: Request](#class-request) | |
- [new Request(input[, options])](#new-requestinput-options) | |
- [Class: Response](#class-response) | |
- [new Response([body[, options]])](#new-responsebody-options) | |
- [response.ok](#responseok) | |
- [response.redirected](#responseredirected) | |
- [response.type](#responsetype) | |
- [Class: Headers](#class-headers) | |
- [new Headers([init])](#new-headersinit) | |
- [Interface: Body](#interface-body) | |
- [body.body](#bodybody) | |
- [body.bodyUsed](#bodybodyused) | |
- [body.arrayBuffer()](#bodyarraybuffer) | |
- [body.blob()](#bodyblob) | |
- [body.formData()](#formdata) | |
- [body.json()](#bodyjson) | |
- [body.text()](#bodytext) | |
- [Class: FetchError](#class-fetcherror) | |
- [Class: AbortError](#class-aborterror) | |
- [TypeScript](#typescript) | |
- [Acknowledgement](#acknowledgement) | |
- [Team](#team) | |
- [Former](#former) | |
- [License](#license) | |
<!-- /TOC --> | |
## Motivation | |
Instead of implementing `XMLHttpRequest` in Node.js to run browser-specific [Fetch polyfill](https://github.com/github/fetch), why not go from native `http` to `fetch` API directly? Hence, `node-fetch`, minimal code for a `window.fetch` compatible API on Node.js runtime. | |
See Jason Miller's [isomorphic-unfetch](https://www.npmjs.com/package/isomorphic-unfetch) or Leonardo Quixada's [cross-fetch](https://github.com/lquixada/cross-fetch) for isomorphic usage (exports `node-fetch` for server-side, `whatwg-fetch` for client-side). | |
## Features | |
- Stay consistent with `window.fetch` API. | |
- Make conscious trade-off when following [WHATWG fetch spec][whatwg-fetch] and [stream spec](https://streams.spec.whatwg.org/) implementation details, document known differences. | |
- Use native promise and async functions. | |
- Use native Node streams for body, on both request and response. | |
- Decode content encoding (gzip/deflate/brotli) properly, and convert string output (such as `res.text()` and `res.json()`) to UTF-8 automatically. | |
- Useful extensions such as redirect limit, response size limit, [explicit errors][error-handling.md] for troubleshooting. | |
## Difference from client-side fetch | |
- See known differences: | |
- [As of v3.x](docs/v3-LIMITS.md) | |
- [As of v2.x](docs/v2-LIMITS.md) | |
- If you happen to use a missing feature that `window.fetch` offers, feel free to open an issue. | |
- Pull requests are welcomed too! | |
## Installation | |
Current stable release (`3.x`) requires at least Node.js 12.20.0. | |
```sh | |
npm install node-fetch | |
``` | |
## Loading and configuring the module | |
### ES Modules (ESM) | |
```js | |
import fetch from 'node-fetch'; | |
``` | |
### CommonJS | |
`node-fetch` from v3 is an ESM-only module - you are not able to import it with `require()`. | |
If you cannot switch to ESM, please use v2 which remains compatible with CommonJS. Critical bug fixes will continue to be published for v2. | |
```sh | |
npm install node-fetch@2 | |
``` | |
Alternatively, you can use the async `import()` function from CommonJS to load `node-fetch` asynchronously: | |
```js | |
// mod.cjs | |
const fetch = (...args) => import('node-fetch').then(({default: fetch}) => fetch(...args)); | |
``` | |
### Providing global access | |
To use `fetch()` without importing it, you can patch the `global` object in node: | |
```js | |
// fetch-polyfill.js | |
import fetch, { | |
Blob, | |
blobFrom, | |
blobFromSync, | |
File, | |
fileFrom, | |
fileFromSync, | |
FormData, | |
Headers, | |
Request, | |
Response, | |
} from 'node-fetch' | |
if (!globalThis.fetch) { | |
globalThis.fetch = fetch | |
globalThis.Headers = Headers | |
globalThis.Request = Request | |
globalThis.Response = Response | |
} | |
// index.js | |
import './fetch-polyfill' | |
// ... | |
``` | |
## Upgrading | |
Using an old version of node-fetch? Check out the following files: | |
- [2.x to 3.x upgrade guide](docs/v3-UPGRADE-GUIDE.md) | |
- [1.x to 2.x upgrade guide](docs/v2-UPGRADE-GUIDE.md) | |
- [Changelog](https://github.com/node-fetch/node-fetch/releases) | |
## Common Usage | |
NOTE: The documentation below is up-to-date with `3.x` releases, if you are using an older version, please check how to [upgrade](#upgrading). | |
### Plain text or HTML | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://github.com/'); | |
const body = await response.text(); | |
console.log(body); | |
``` | |
### JSON | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://api.github.com/users/github'); | |
const data = await response.json(); | |
console.log(data); | |
``` | |
### Simple Post | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://httpbin.org/post', {method: 'POST', body: 'a=1'}); | |
const data = await response.json(); | |
console.log(data); | |
``` | |
### Post with JSON | |
```js | |
import fetch from 'node-fetch'; | |
const body = {a: 1}; | |
const response = await fetch('https://httpbin.org/post', { | |
method: 'post', | |
body: JSON.stringify(body), | |
headers: {'Content-Type': 'application/json'} | |
}); | |
const data = await response.json(); | |
console.log(data); | |
``` | |
### Post with form parameters | |
`URLSearchParams` is available on the global object in Node.js as of v10.0.0. See [official documentation](https://nodejs.org/api/url.html#url_class_urlsearchparams) for more usage methods. | |
NOTE: The `Content-Type` header is only set automatically to `x-www-form-urlencoded` when an instance of `URLSearchParams` is given as such: | |
```js | |
import fetch from 'node-fetch'; | |
const params = new URLSearchParams(); | |
params.append('a', 1); | |
const response = await fetch('https://httpbin.org/post', {method: 'POST', body: params}); | |
const data = await response.json(); | |
console.log(data); | |
``` | |
### Handling exceptions | |
NOTE: 3xx-5xx responses are _NOT_ exceptions, and should be handled in `then()`, see the next section. | |
Wrapping the fetch function into a `try/catch` block will catch _all_ exceptions, such as errors originating from node core libraries, like network errors, and operational errors which are instances of FetchError. See the [error handling document][error-handling.md] for more details. | |
```js | |
import fetch from 'node-fetch'; | |
try { | |
await fetch('https://domain.invalid/'); | |
} catch (error) { | |
console.log(error); | |
} | |
``` | |
### Handling client and server errors | |
It is common to create a helper function to check that the response contains no client (4xx) or server (5xx) error responses: | |
```js | |
import fetch from 'node-fetch'; | |
class HTTPResponseError extends Error { | |
constructor(response) { | |
super(`HTTP Error Response: ${response.status} ${response.statusText}`); | |
this.response = response; | |
} | |
} | |
const checkStatus = response => { | |
if (response.ok) { | |
// response.status >= 200 && response.status < 300 | |
return response; | |
} else { | |
throw new HTTPResponseError(response); | |
} | |
} | |
const response = await fetch('https://httpbin.org/status/400'); | |
try { | |
checkStatus(response); | |
} catch (error) { | |
console.error(error); | |
const errorBody = await error.response.text(); | |
console.error(`Error body: ${errorBody}`); | |
} | |
``` | |
### Handling cookies | |
Cookies are not stored by default. However, cookies can be extracted and passed by manipulating request and response headers. See [Extract Set-Cookie Header](#extract-set-cookie-header) for details. | |
## Advanced Usage | |
### Streams | |
The "Node.js way" is to use streams when possible. You can pipe `res.body` to another stream. This example uses [stream.pipeline](https://nodejs.org/api/stream.html#stream_stream_pipeline_streams_callback) to attach stream error handlers and wait for the download to complete. | |
```js | |
import {createWriteStream} from 'node:fs'; | |
import {pipeline} from 'node:stream'; | |
import {promisify} from 'node:util' | |
import fetch from 'node-fetch'; | |
const streamPipeline = promisify(pipeline); | |
const response = await fetch('https://github.githubassets.com/images/modules/logos_page/Octocat.png'); | |
if (!response.ok) throw new Error(`unexpected response ${response.statusText}`); | |
await streamPipeline(response.body, createWriteStream('./octocat.png')); | |
``` | |
In Node.js 14 you can also use async iterators to read `body`; however, be careful to catch | |
errors -- the longer a response runs, the more likely it is to encounter an error. | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://httpbin.org/stream/3'); | |
try { | |
for await (const chunk of response.body) { | |
console.dir(JSON.parse(chunk.toString())); | |
} | |
} catch (err) { | |
console.error(err.stack); | |
} | |
``` | |
In Node.js 12 you can also use async iterators to read `body`; however, async iterators with streams | |
did not mature until Node.js 14, so you need to do some extra work to ensure you handle errors | |
directly from the stream and wait on it response to fully close. | |
```js | |
import fetch from 'node-fetch'; | |
const read = async body => { | |
let error; | |
body.on('error', err => { | |
error = err; | |
}); | |
for await (const chunk of body) { | |
console.dir(JSON.parse(chunk.toString())); | |
} | |
return new Promise((resolve, reject) => { | |
body.on('close', () => { | |
error ? reject(error) : resolve(); | |
}); | |
}); | |
}; | |
try { | |
const response = await fetch('https://httpbin.org/stream/3'); | |
await read(response.body); | |
} catch (err) { | |
console.error(err.stack); | |
} | |
``` | |
### Accessing Headers and other Metadata | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://github.com/'); | |
console.log(response.ok); | |
console.log(response.status); | |
console.log(response.statusText); | |
console.log(response.headers.raw()); | |
console.log(response.headers.get('content-type')); | |
``` | |
### Extract Set-Cookie Header | |
Unlike browsers, you can access raw `Set-Cookie` headers manually using `Headers.raw()`. This is a `node-fetch` only API. | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://example.com'); | |
// Returns an array of values, instead of a string of comma-separated values | |
console.log(response.headers.raw()['set-cookie']); | |
``` | |
### Post data using a file | |
```js | |
import fetch, { | |
Blob, | |
blobFrom, | |
blobFromSync, | |
File, | |
fileFrom, | |
fileFromSync, | |
} from 'node-fetch' | |
const mimetype = 'text/plain' | |
const blob = fileFromSync('./input.txt', mimetype) | |
const url = 'https://httpbin.org/post' | |
const response = await fetch(url, { method: 'POST', body: blob }) | |
const data = await response.json() | |
console.log(data) | |
``` | |
node-fetch comes with a spec-compliant [FormData] implementations for posting | |
multipart/form-data payloads | |
```js | |
import fetch, { FormData, File, fileFrom } from 'node-fetch' | |
const httpbin = 'https://httpbin.org/post' | |
const formData = new FormData() | |
const binary = new Uint8Array([ 97, 98, 99 ]) | |
const abc = new File([binary], 'abc.txt', { type: 'text/plain' }) | |
formData.set('greeting', 'Hello, world!') | |
formData.set('file-upload', abc, 'new name.txt') | |
const response = await fetch(httpbin, { method: 'POST', body: formData }) | |
const data = await response.json() | |
console.log(data) | |
``` | |
If you for some reason need to post a stream coming from any arbitrary place, | |
then you can append a [Blob] or a [File] look-a-like item. | |
The minimum requirement is that it has: | |
1. A `Symbol.toStringTag` getter or property that is either `Blob` or `File` | |
2. A known size. | |
3. And either a `stream()` method or a `arrayBuffer()` method that returns a ArrayBuffer. | |
The `stream()` must return any async iterable object as long as it yields Uint8Array (or Buffer) | |
so Node.Readable streams and whatwg streams works just fine. | |
```js | |
formData.append('upload', { | |
[Symbol.toStringTag]: 'Blob', | |
size: 3, | |
*stream() { | |
yield new Uint8Array([97, 98, 99]) | |
}, | |
arrayBuffer() { | |
return new Uint8Array([97, 98, 99]).buffer | |
} | |
}, 'abc.txt') | |
``` | |
### Request cancellation with AbortSignal | |
You may cancel requests with `AbortController`. A suggested implementation is [`abort-controller`](https://www.npmjs.com/package/abort-controller). | |
An example of timing out a request after 150ms could be achieved as the following: | |
```js | |
import fetch, { AbortError } from 'node-fetch'; | |
// AbortController was added in node v14.17.0 globally | |
const AbortController = globalThis.AbortController || await import('abort-controller') | |
const controller = new AbortController(); | |
const timeout = setTimeout(() => { | |
controller.abort(); | |
}, 150); | |
try { | |
const response = await fetch('https://example.com', {signal: controller.signal}); | |
const data = await response.json(); | |
} catch (error) { | |
if (error instanceof AbortError) { | |
console.log('request was aborted'); | |
} | |
} finally { | |
clearTimeout(timeout); | |
} | |
``` | |
See [test cases](https://github.com/node-fetch/node-fetch/blob/master/test/) for more examples. | |
## API | |
### fetch(url[, options]) | |
- `url` A string representing the URL for fetching | |
- `options` [Options](#fetch-options) for the HTTP(S) request | |
- Returns: <code>Promise<[Response](#class-response)></code> | |
Perform an HTTP(S) fetch. | |
`url` should be an absolute URL, such as `https://example.com/`. A path-relative URL (`/file/under/root`) or protocol-relative URL (`//can-be-http-or-https.com/`) will result in a rejected `Promise`. | |
<a id="fetch-options"></a> | |
### Options | |
The default values are shown after each option key. | |
```js | |
{ | |
// These properties are part of the Fetch Standard | |
method: 'GET', | |
headers: {}, // Request headers. format is the identical to that accepted by the Headers constructor (see below) | |
body: null, // Request body. can be null, or a Node.js Readable stream | |
redirect: 'follow', // Set to `manual` to extract redirect headers, `error` to reject redirect | |
signal: null, // Pass an instance of AbortSignal to optionally abort requests | |
// The following properties are node-fetch extensions | |
follow: 20, // maximum redirect count. 0 to not follow redirect | |
compress: true, // support gzip/deflate content encoding. false to disable | |
size: 0, // maximum response body size in bytes. 0 to disable | |
agent: null, // http(s).Agent instance or function that returns an instance (see below) | |
highWaterMark: 16384, // the maximum number of bytes to store in the internal buffer before ceasing to read from the underlying resource. | |
insecureHTTPParser: false // Use an insecure HTTP parser that accepts invalid HTTP headers when `true`. | |
} | |
``` | |
#### Default Headers | |
If no values are set, the following request headers will be sent automatically: | |
| Header | Value | | |
| ------------------- | ------------------------------------------------------ | | |
| `Accept-Encoding` | `gzip, deflate, br` (when `options.compress === true`) | | |
| `Accept` | `*/*` | | |
| `Content-Length` | _(automatically calculated, if possible)_ | | |
| `Host` | _(host and port information from the target URI)_ | | |
| `Transfer-Encoding` | `chunked` _(when `req.body` is a stream)_ | | |
| `User-Agent` | `node-fetch` | | |
Note: when `body` is a `Stream`, `Content-Length` is not set automatically. | |
#### Custom Agent | |
The `agent` option allows you to specify networking related options which are out of the scope of Fetch, including and not limited to the following: | |
- Support self-signed certificate | |
- Use only IPv4 or IPv6 | |
- Custom DNS Lookup | |
See [`http.Agent`](https://nodejs.org/api/http.html#http_new_agent_options) for more information. | |
If no agent is specified, the default agent provided by Node.js is used. Note that [this changed in Node.js 19](https://github.com/nodejs/node/blob/4267b92604ad78584244488e7f7508a690cb80d0/lib/_http_agent.js#L564) to have `keepalive` true by default. If you wish to enable `keepalive` in an earlier version of Node.js, you can override the agent as per the following code sample. | |
In addition, the `agent` option accepts a function that returns `http`(s)`.Agent` instance given current [URL](https://nodejs.org/api/url.html), this is useful during a redirection chain across HTTP and HTTPS protocol. | |
```js | |
import http from 'node:http'; | |
import https from 'node:https'; | |
const httpAgent = new http.Agent({ | |
keepAlive: true | |
}); | |
const httpsAgent = new https.Agent({ | |
keepAlive: true | |
}); | |
const options = { | |
agent: function(_parsedURL) { | |
if (_parsedURL.protocol == 'http:') { | |
return httpAgent; | |
} else { | |
return httpsAgent; | |
} | |
} | |
}; | |
``` | |
<a id="custom-highWaterMark"></a> | |
#### Custom highWaterMark | |
Stream on Node.js have a smaller internal buffer size (16kB, aka `highWaterMark`) from client-side browsers (>1MB, not consistent across browsers). Because of that, when you are writing an isomorphic app and using `res.clone()`, it will hang with large response in Node. | |
The recommended way to fix this problem is to resolve cloned response in parallel: | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://example.com'); | |
const r1 = response.clone(); | |
const results = await Promise.all([response.json(), r1.text()]); | |
console.log(results[0]); | |
console.log(results[1]); | |
``` | |
If for some reason you don't like the solution above, since `3.x` you are able to modify the `highWaterMark` option: | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://example.com', { | |
// About 1MB | |
highWaterMark: 1024 * 1024 | |
}); | |
const result = await res.clone().arrayBuffer(); | |
console.dir(result); | |
``` | |
#### Insecure HTTP Parser | |
Passed through to the `insecureHTTPParser` option on http(s).request. See [`http.request`](https://nodejs.org/api/http.html#http_http_request_url_options_callback) for more information. | |
#### Manual Redirect | |
The `redirect: 'manual'` option for node-fetch is different from the browser & specification, which | |
results in an [opaque-redirect filtered response](https://fetch.spec.whatwg.org/#concept-filtered-response-opaque-redirect). | |
node-fetch gives you the typical [basic filtered response](https://fetch.spec.whatwg.org/#concept-filtered-response-basic) instead. | |
```js | |
import fetch from 'node-fetch'; | |
const response = await fetch('https://httpbin.org/status/301', { redirect: 'manual' }); | |
if (response.status === 301 || response.status === 302) { | |
const locationURL = new URL(response.headers.get('location'), response.url); | |
const response2 = await fetch(locationURL, { redirect: 'manual' }); | |
console.dir(response2); | |
} | |
``` | |
<a id="class-request"></a> | |
### Class: Request | |
An HTTP(S) request containing information about URL, method, headers, and the body. This class implements the [Body](#iface-body) interface. | |
Due to the nature of Node.js, the following properties are not implemented at this moment: | |
- `type` | |
- `destination` | |
- `mode` | |
- `credentials` | |
- `cache` | |
- `integrity` | |
- `keepalive` | |
The following node-fetch extension properties are provided: | |
- `follow` | |
- `compress` | |
- `counter` | |
- `agent` | |
- `highWaterMark` | |
See [options](#fetch-options) for exact meaning of these extensions. | |
#### new Request(input[, options]) | |
<small>_(spec-compliant)_</small> | |
- `input` A string representing a URL, or another `Request` (which will be cloned) | |
- `options` [Options](#fetch-options) for the HTTP(S) request | |
Constructs a new `Request` object. The constructor is identical to that in the [browser](https://developer.mozilla.org/en-US/docs/Web/API/Request/Request). | |
In most cases, directly `fetch(url, options)` is simpler than creating a `Request` object. | |
<a id="class-response"></a> | |
### Class: Response | |
An HTTP(S) response. This class implements the [Body](#iface-body) interface. | |
The following properties are not implemented in node-fetch at this moment: | |
- `trailer` | |
#### new Response([body[, options]]) | |
<small>_(spec-compliant)_</small> | |
- `body` A `String` or [`Readable` stream][node-readable] | |
- `options` A [`ResponseInit`][response-init] options dictionary | |
Constructs a new `Response` object. The constructor is identical to that in the [browser](https://developer.mozilla.org/en-US/docs/Web/API/Response/Response). | |
Because Node.js does not implement service workers (for which this class was designed), one rarely has to construct a `Response` directly. | |
#### response.ok | |
<small>_(spec-compliant)_</small> | |
Convenience property representing if the request ended normally. Will evaluate to true if the response status was greater than or equal to 200 but smaller than 300. | |
#### response.redirected | |
<small>_(spec-compliant)_</small> | |
Convenience property representing if the request has been redirected at least once. Will evaluate to true if the internal redirect counter is greater than 0. | |
#### response.type | |
<small>_(deviation from spec)_</small> | |
Convenience property representing the response's type. node-fetch only supports `'default'` and `'error'` and does not make use of [filtered responses](https://fetch.spec.whatwg.org/#concept-filtered-response). | |
<a id="class-headers"></a> | |
### Class: Headers | |
This class allows manipulating and iterating over a set of HTTP headers. All methods specified in the [Fetch Standard][whatwg-fetch] are implemented. | |
#### new Headers([init]) | |
<small>_(spec-compliant)_</small> | |
- `init` Optional argument to pre-fill the `Headers` object | |
Construct a new `Headers` object. `init` can be either `null`, a `Headers` object, an key-value map object or any iterable object. | |
```js | |
// Example adapted from https://fetch.spec.whatwg.org/#example-headers-class | |
import {Headers} from 'node-fetch'; | |
const meta = { | |
'Content-Type': 'text/xml' | |
}; | |
const headers = new Headers(meta); | |
// The above is equivalent to | |
const meta = [['Content-Type', 'text/xml']]; | |
const headers = new Headers(meta); | |
// You can in fact use any iterable objects, like a Map or even another Headers | |
const meta = new Map(); | |
meta.set('Content-Type', 'text/xml'); | |
const headers = new Headers(meta); | |
const copyOfHeaders = new Headers(headers); | |
``` | |
<a id="iface-body"></a> | |
### Interface: Body | |
`Body` is an abstract interface with methods that are applicable to both `Request` and `Response` classes. | |
#### body.body | |
<small>_(deviation from spec)_</small> | |
- Node.js [`Readable` stream][node-readable] | |
Data are encapsulated in the `Body` object. Note that while the [Fetch Standard][whatwg-fetch] requires the property to always be a WHATWG `ReadableStream`, in node-fetch it is a Node.js [`Readable` stream][node-readable]. | |
#### body.bodyUsed | |
<small>_(spec-compliant)_</small> | |
- `Boolean` | |
A boolean property for if this body has been consumed. Per the specs, a consumed body cannot be used again. | |
#### body.arrayBuffer() | |
#### body.formData() | |
#### body.blob() | |
#### body.json() | |
#### body.text() | |
`fetch` comes with methods to parse `multipart/form-data` payloads as well as | |
`x-www-form-urlencoded` bodies using `.formData()` this comes from the idea that | |
Service Worker can intercept such messages before it's sent to the server to | |
alter them. This is useful for anybody building a server so you can use it to | |
parse & consume payloads. | |
<details> | |
<summary>Code example</summary> | |
```js | |
import http from 'node:http' | |
import { Response } from 'node-fetch' | |
http.createServer(async function (req, res) { | |
const formData = await new Response(req, { | |
headers: req.headers // Pass along the boundary value | |
}).formData() | |
const allFields = [...formData] | |
const file = formData.get('uploaded-files') | |
const arrayBuffer = await file.arrayBuffer() | |
const text = await file.text() | |
const whatwgReadableStream = file.stream() | |
// other was to consume the request could be to do: | |
const json = await new Response(req).json() | |
const text = await new Response(req).text() | |
const arrayBuffer = await new Response(req).arrayBuffer() | |
const blob = await new Response(req, { | |
headers: req.headers // So that `type` inherits `Content-Type` | |
}.blob() | |
}) | |
``` | |
</details> | |
<a id="class-fetcherror"></a> | |
### Class: FetchError | |
<small>_(node-fetch extension)_</small> | |
An operational error in the fetching process. See [ERROR-HANDLING.md][] for more info. | |
<a id="class-aborterror"></a> | |
### Class: AbortError | |
<small>_(node-fetch extension)_</small> | |
An Error thrown when the request is aborted in response to an `AbortSignal`'s `abort` event. It has a `name` property of `AbortError`. See [ERROR-HANDLING.MD][] for more info. | |
## TypeScript | |
**Since `3.x` types are bundled with `node-fetch`, so you don't need to install any additional packages.** | |
For older versions please use the type definitions from [DefinitelyTyped](https://github.com/DefinitelyTyped/DefinitelyTyped): | |
```sh | |
npm install --save-dev @types/node-fetch@2.x | |
``` | |
## Acknowledgement | |
Thanks to [github/fetch](https://github.com/github/fetch) for providing a solid implementation reference. | |
## Team | |
| [![David Frank](https://github.com/bitinn.png?size=100)](https://github.com/bitinn) | [![Jimmy Wärting](https://github.com/jimmywarting.png?size=100)](https://github.com/jimmywarting) | [![Antoni Kepinski](https://github.com/xxczaki.png?size=100)](https://github.com/xxczaki) | [![Richie Bendall](https://github.com/Richienb.png?size=100)](https://github.com/Richienb) | [![Gregor Martynus](https://github.com/gr2m.png?size=100)](https://github.com/gr2m) | | |
| ----------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------- | | |
| [David Frank](https://bitinn.net/) | [Jimmy Wärting](https://jimmy.warting.se/) | [Antoni Kepinski](https://kepinski.ch) | [Richie Bendall](https://www.richie-bendall.ml/) | [Gregor Martynus](https://twitter.com/gr2m) | | |
###### Former | |
- [Timothy Gu](https://github.com/timothygu) | |
- [Jared Kantrowitz](https://github.com/jkantr) | |
## License | |
[MIT](LICENSE.md) | |
[whatwg-fetch]: https://fetch.spec.whatwg.org/ | |
[response-init]: https://fetch.spec.whatwg.org/#responseinit | |
[node-readable]: https://nodejs.org/api/stream.html#stream_readable_streams | |
[mdn-headers]: https://developer.mozilla.org/en-US/docs/Web/API/Headers | |
[error-handling.md]: https://github.com/node-fetch/node-fetch/blob/master/docs/ERROR-HANDLING.md | |
[FormData]: https://developer.mozilla.org/en-US/docs/Web/API/FormData | |
[Blob]: https://developer.mozilla.org/en-US/docs/Web/API/Blob | |
[File]: https://developer.mozilla.org/en-US/docs/Web/API/File | |