1# Form-Data [![NPM Module](https://img.shields.io/npm/v/form-data.svg)](https://www.npmjs.com/package/form-data) [![Join the chat at https://gitter.im/form-data/form-data](http://form-data.github.io/images/gitterbadge.svg)](https://gitter.im/form-data/form-data)
2
3A library to create readable ```"multipart/form-data"``` streams. Can be used to submit forms and file uploads to other web applications.
4
5The API of this library is inspired by the [XMLHttpRequest-2 FormData Interface][xhr2-fd].
6
7[xhr2-fd]: http://dev.w3.org/2006/webapi/XMLHttpRequest-2/Overview.html#the-formdata-interface
8
9[![Linux Build](https://img.shields.io/travis/form-data/form-data/v2.3.3.svg?label=linux:4.x-9.x)](https://travis-ci.org/form-data/form-data)
10[![MacOS Build](https://img.shields.io/travis/form-data/form-data/v2.3.3.svg?label=macos:4.x-9.x)](https://travis-ci.org/form-data/form-data)
11[![Windows Build](https://img.shields.io/appveyor/ci/alexindigo/form-data/v2.3.3.svg?label=windows:4.x-9.x)](https://ci.appveyor.com/project/alexindigo/form-data)
12
13[![Coverage Status](https://img.shields.io/coveralls/form-data/form-data/v2.3.3.svg?label=code+coverage)](https://coveralls.io/github/form-data/form-data?branch=master)
14[![Dependency Status](https://img.shields.io/david/form-data/form-data.svg)](https://david-dm.org/form-data/form-data)
15[![bitHound Overall Score](https://www.bithound.io/github/form-data/form-data/badges/score.svg)](https://www.bithound.io/github/form-data/form-data)
16
17## Install
18
19```
20npm install --save form-data
21```
22
23## Usage
24
25In this example we are constructing a form with 3 fields that contain a string,
26a buffer and a file stream.
27
28``` javascript
29var FormData = require('form-data');
30var fs = require('fs');
31
32var form = new FormData();
33form.append('my_field', 'my value');
34form.append('my_buffer', new Buffer(10));
35form.append('my_file', fs.createReadStream('/foo/bar.jpg'));
36```
37
38Also you can use http-response stream:
39
40``` javascript
41var FormData = require('form-data');
42var http = require('http');
43
44var form = new FormData();
45
46http.request('http://nodejs.org/images/logo.png', function(response) {
47  form.append('my_field', 'my value');
48  form.append('my_buffer', new Buffer(10));
49  form.append('my_logo', response);
50});
51```
52
53Or @mikeal's [request](https://github.com/request/request) stream:
54
55``` javascript
56var FormData = require('form-data');
57var request = require('request');
58
59var form = new FormData();
60
61form.append('my_field', 'my value');
62form.append('my_buffer', new Buffer(10));
63form.append('my_logo', request('http://nodejs.org/images/logo.png'));
64```
65
66In order to submit this form to a web application, call ```submit(url, [callback])``` method:
67
68``` javascript
69form.submit('http://example.org/', function(err, res) {
70  // res – response object (http.IncomingMessage)  //
71  res.resume();
72});
73
74```
75
76For more advanced request manipulations ```submit()``` method returns ```http.ClientRequest``` object, or you can choose from one of the alternative submission methods.
77
78### Custom options
79
80You can provide custom options, such as `maxDataSize`:
81
82``` javascript
83var FormData = require('form-data');
84
85var form = new FormData({ maxDataSize: 20971520 });
86form.append('my_field', 'my value');
87form.append('my_buffer', /* something big */);
88```
89
90List of available options could be found in [combined-stream](https://github.com/felixge/node-combined-stream/blob/master/lib/combined_stream.js#L7-L15)
91
92### Alternative submission methods
93
94You can use node's http client interface:
95
96``` javascript
97var http = require('http');
98
99var request = http.request({
100  method: 'post',
101  host: 'example.org',
102  path: '/upload',
103  headers: form.getHeaders()
104});
105
106form.pipe(request);
107
108request.on('response', function(res) {
109  console.log(res.statusCode);
110});
111```
112
113Or if you would prefer the `'Content-Length'` header to be set for you:
114
115``` javascript
116form.submit('example.org/upload', function(err, res) {
117  console.log(res.statusCode);
118});
119```
120
121To use custom headers and pre-known length in parts:
122
123``` javascript
124var CRLF = '\r\n';
125var form = new FormData();
126
127var options = {
128  header: CRLF + '--' + form.getBoundary() + CRLF + 'X-Custom-Header: 123' + CRLF + CRLF,
129  knownLength: 1
130};
131
132form.append('my_buffer', buffer, options);
133
134form.submit('http://example.com/', function(err, res) {
135  if (err) throw err;
136  console.log('Done');
137});
138```
139
140Form-Data can recognize and fetch all the required information from common types of streams (```fs.readStream```, ```http.response``` and ```mikeal's request```), for some other types of streams you'd need to provide "file"-related information manually:
141
142``` javascript
143someModule.stream(function(err, stdout, stderr) {
144  if (err) throw err;
145
146  var form = new FormData();
147
148  form.append('file', stdout, {
149    filename: 'unicycle.jpg', // ... or:
150    filepath: 'photos/toys/unicycle.jpg',
151    contentType: 'image/jpeg',
152    knownLength: 19806
153  });
154
155  form.submit('http://example.com/', function(err, res) {
156    if (err) throw err;
157    console.log('Done');
158  });
159});
160```
161
162The `filepath` property overrides `filename` and may contain a relative path. This is typically used when uploading [multiple files from a directory](https://wicg.github.io/entries-api/#dom-htmlinputelement-webkitdirectory).
163
164For edge cases, like POST request to URL with query string or to pass HTTP auth credentials, object can be passed to `form.submit()` as first parameter:
165
166``` javascript
167form.submit({
168  host: 'example.com',
169  path: '/probably.php?extra=params',
170  auth: 'username:password'
171}, function(err, res) {
172  console.log(res.statusCode);
173});
174```
175
176In case you need to also send custom HTTP headers with the POST request, you can use the `headers` key in first parameter of `form.submit()`:
177
178``` javascript
179form.submit({
180  host: 'example.com',
181  path: '/surelynot.php',
182  headers: {'x-test-header': 'test-header-value'}
183}, function(err, res) {
184  console.log(res.statusCode);
185});
186```
187
188### Integration with other libraries
189
190#### Request
191
192Form submission using  [request](https://github.com/request/request):
193
194```javascript
195var formData = {
196  my_field: 'my_value',
197  my_file: fs.createReadStream(__dirname + '/unicycle.jpg'),
198};
199
200request.post({url:'http://service.com/upload', formData: formData}, function(err, httpResponse, body) {
201  if (err) {
202    return console.error('upload failed:', err);
203  }
204  console.log('Upload successful!  Server responded with:', body);
205});
206```
207
208For more details see [request readme](https://github.com/request/request#multipartform-data-multipart-form-uploads).
209
210#### node-fetch
211
212You can also submit a form using [node-fetch](https://github.com/bitinn/node-fetch):
213
214```javascript
215var form = new FormData();
216
217form.append('a', 1);
218
219fetch('http://example.com', { method: 'POST', body: form })
220    .then(function(res) {
221        return res.json();
222    }).then(function(json) {
223        console.log(json);
224    });
225```
226
227## Notes
228
229- ```getLengthSync()``` method DOESN'T calculate length for streams, use ```knownLength``` options as workaround.
230- Starting version `2.x` FormData has dropped support for `node@0.10.x`.
231
232## License
233
234Form-Data is released under the [MIT](License) license.
235