You can also stream a file to a PUT or POST request. This method will also check the file extension against a mapping of file extensions to content-types (in this case `application/json`) and use the proper `content-type` in the PUT request (if the headers don’t already provide one).
Request emits a "response" event when a response is received. The `response` argument will be an instance of [http.IncomingMessage](http://nodejs.org/api/http.html#http_http_incomingmessage).
You can also `pipe()` from `http.ServerRequest` instances, as well as to `http.ServerResponse` instances. The HTTP method, headers, and entity-body data will be sent. Which means that, if you don't really care about security, you can do:
For `multipart/form-data` we use the [form-data](https://github.com/felixge/node-form-data) library by [@felixge](https://github.com/felixge). For the most cases, you can pass your upload form data via the `formData` option.
For advanced cases, you can access the form-data object itself via `r.form()`. This can be modified until the request is fired on the next cycle of the event-loop. (Note that this calling `form()` will clear the currently set form data for that request.)
Some variations in different HTTP implementations require a newline/CRLF before, after, or both before and after the boundary of a `multipart/related` request (using the multipart option). This has been observed in the .NET WebAPI version 4.0. You can turn on a boundary preambleCRLF or postamble by passing them as `true` to your request options.
and then the proxy server make a TCP connection to `endpoint-server`
on port `80`, and return a response that looks like:
```
HTTP/1.1 200 OK
```
At this point, the connection is left open, and the client is
communicating directly with the `endpoint-server.com` machine.
See [the wikipedia page on HTTP Tunneling](http://en.wikipedia.org/wiki/HTTP_tunnel)
for more information.
By default, when proxying `http` traffic, request will simply make a
standard proxied `http` request. This is done by making the `url`
section of the initial line of the request a fully qualified url to
the endpoint.
For example, it will make a single request that looks like:
```
HTTP/1.1 GET http://endpoint-server.com/some-url
Host: proxy-server.com
Other-Headers: all go here
request body or whatever
```
Because a pure "http over http" tunnel offers no additional security
or other features, it is generally simpler to go with a
straightforward HTTP proxy in this case. However, if you would like
to force a tunneling proxy, you may set the `tunnel` option to `true`.
You can also make a standard proxied `http` request by explicitly setting
`tunnel : false`, but **note that this will allow the proxy to see the traffic
to/from the destination server**.
If you are using a tunneling proxy, you may set the
`proxyHeaderWhiteList` to share certain headers with the proxy.
You can also set the `proxyHeaderExclusiveList` to share certain
headers only with the proxy and not with destination host.
By default, this set is:
```
accept
accept-charset
accept-encoding
accept-language
accept-ranges
cache-control
content-encoding
content-language
content-length
content-location
content-md5
content-range
content-type
connection
date
expect
max-forwards
pragma
proxy-authorization
referer
te
transfer-encoding
user-agent
via
```
Note that, when using a tunneling proxy, the `proxy-authorization`
header and any headers from custom `proxyHeaderExclusiveList` are
*never* sent to the endpoint server, but only to the proxy server.
### Controlling proxy behaviour using environment variables
The following environment variables are respected by `request`:
*`HTTP_PROXY` / `http_proxy`
*`HTTPS_PROXY` / `https_proxy`
*`NO_PROXY` / `no_proxy`
When `HTTP_PROXY` / `http_proxy` are set, they will be used to proxy non-SSL requests that do not have an explicit `proxy` configuration option present. Similarly, `HTTPS_PROXY` / `https_proxy` will be respected for SSL requests that do not have an explicit `proxy` configuration option. It is valid to define a proxy in one of the environment variables, but then override it for a specific request, using the `proxy` configuration option. Furthermore, the `proxy` configuration option can be explicitly set to false / null to opt out of proxying altogether for that request.
`request` is also aware of the `NO_PROXY`/`no_proxy` environment variables. These variables provide a granular way to opt out of proxying, on a per-host basis. It should contain a comma separated list of hosts to opt out of proxying. It is also possible to opt of proxying when a particular destination port is used. Finally, the variable may be set to `*` to opt out of the implicit proxy configuration of the other environment variables.
Here's some examples of valid `no_proxy` values:
*`google.com` - don't proxy HTTP/HTTPS requests to Google.
*`google.com:443` - don't proxy HTTPS requests to Google, but *do* proxy HTTP requests to Google.
*`google.com:443, yahoo.com:80` - don't proxy HTTPS requests to Google, and don't proxy HTTP requests to Yahoo!
`request` supports making requests to [UNIX Domain Sockets](http://en.wikipedia.org/wiki/Unix_domain_socket). To make one, use the following URL scheme:
```js
/* Pattern */ 'http://unix:SOCKET:PATH'
/* Example */ request.get('http://unix:/absolute/path/to/unix.socket:/request/path')
```
Note: The `SOCKET` path is assumed to be absolute to the root of the host file system.
set directly in `options` object, in the `agentOptions` property of the `options` object, or even in `https.globalAgent.options`. Keep in mind that, although `agentOptions` allows for a slightly wider range of configurations, the recommendend way is via `options` object directly, as using `agentOptions` or `https.globalAgent.options` would not be applied in the same way in proxied environments (as data travels through a TLS connection instead of an http/https agent).
The `options.har` property will override the values: `url`, `method`, `qs`, `headers`, `form`, `formData`, `body`, `json`, as well as construct multipart data and read files from disk when `request.postData.params[].fileName` is present without a matching `value`.
a validation step will check if the HAR Request format matches the latest spec (v1.2) and will skip parsing if not matching.
-`uri` || `url` - fully qualified uri or a parsed url object from `url.parse()`
-`baseUrl` - fully qualified uri string used as the base url. Most useful with `request.defaults`, for example when you want to do many requests to the same domain. If `baseUrl` is `https://example.com/api/`, then requesting `/end/point?test=true` will fetch `https://example.com/api/end/point?test=true`. When `baseUrl` is given, `uri` must also be a string.
-`method` - http method (default: `"GET"`)
-`headers` - http headers (default: `{}`)
---
-`qs` - object containing querystring values to be appended to the `uri`
-`qsParseOptions` - object containing options to pass to the [qs.parse](https://github.com/hapijs/qs#parsing-objects) method. Alternatively pass options to the [querystring.parse](https://nodejs.org/docs/v0.12.0/api/querystring.html#querystring_querystring_parse_str_sep_eq_options) method using this format `{sep:';', eq:':', options:{}}`
-`qsStringifyOptions` - object containing options to pass to the [qs.stringify](https://github.com/hapijs/qs#stringifying) method. Alternatively pass options to the [querystring.stringify](https://nodejs.org/docs/v0.12.0/api/querystring.html#querystring_querystring_stringify_obj_sep_eq_options) method using this format `{sep:';', eq:':', options:{}}`. For example, to change the way arrays are converted to query strings using the `qs` module pass the `arrayFormat` option with one of `indices|brackets|repeat`
-`body` - entity body for PATCH, POST and PUT requests. Must be a `Buffer` or `String`, unless `json` is `true`. If `json` is `true`, then `body` must be a JSON-serializable object.
-`form` - when passed an object or a querystring, this sets `body` to a querystring representation of value, and adds `Content-type: application/x-www-form-urlencoded` header. When passed no options, a `FormData` instance is returned (and is piped to request). See "Forms" section above.
-`formData` - Data to pass for a `multipart/form-data` request. See
-`preambleCRLF` - append a newline/CRLF before the boundary of your `multipart/form-data` request.
-`postambleCRLF` - append a newline/CRLF at the end of the boundary of your `multipart/form-data` request.
-`json` - sets `body` but to JSON representation of value and adds `Content-type: application/json` header. Additionally, parses the response body as JSON.
-`jsonReviver` - a [reviver function](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse) that will be passed to `JSON.parse()` when parsing a JSON response body.
---
-`auth` - A hash containing values `user` || `username`, `pass` || `password`, and `sendImmediately` (optional). See documentation above.
-`oauth` - Options for OAuth HMAC-SHA1 signing. See documentation above.
-`hawk` - Options for [Hawk signing](https://github.com/hueniverse/hawk). The `credentials` key must contain the necessary signing info, [see hawk docs for details](https://github.com/hueniverse/hawk#usage-example).
-`aws` - `object` containing AWS signing information. Should have the properties `key`, `secret`. Also requires the property `bucket`, unless you’re specifying your `bucket` as part of the path, or the request doesn’t use a bucket (i.e. GET Services)
-`httpSignature` - Options for the [HTTP Signature Scheme](https://github.com/joyent/node-http-signature/blob/master/http_signing.md) using [Joyent's library](https://github.com/joyent/node-http-signature). The `keyId` and `key` properties must be specified. See the docs for other options.
---
-`followRedirect` - follow HTTP 3xx responses as redirects (default: `true`). This property can also be implemented as function which gets `response` object as a single argument and should return `true` if redirects should continue or `false` otherwise.
-`encoding` - Encoding to be used on `setEncoding` of response data. If `null`, the `body` is returned as a `Buffer`. Anything else **(including the default value of `undefined`)** will be passed as the [encoding](http://nodejs.org/api/buffer.html#buffer_buffer) parameter to `toString()` (meaning this is effectively `utf8` by default). (**Note:** if you expect binary data, you should set `encoding: null`.)
-`gzip` - If `true`, add an `Accept-Encoding` header to request compressed content encodings from the server (if not already present) and decode supported content encodings in the response. **Note:** Automatic decoding of the response content is performed on the body data returned through `request` (both through the `request` stream and passed to the callback function) but is not performed on the `response` stream (available from the `response` event) which is the unmodified `http.IncomingMessage` object which may contain compressed data. See example below.
-`jar` - If `true` and `tough-cookie` is installed, remember cookies for future use (or define your custom cookie jar; see examples section)
-`agentClass` - alternatively specify your agent's class name
-`agentOptions` - and pass its options. **Note:** for HTTPS see [tls API doc for TLS/SSL options](http://nodejs.org/api/tls.html#tls_tls_connect_options_callback) and the [documentation above](#using-optionsagentoptions).
-`forever` - set to `true` to use the [forever-agent](https://github.com/request/forever-agent) **Note:** Defaults to `http(s).Agent({keepAlive:true})` in node 0.12+
-`pool` - An object describing which agents to use for the request. If this option is omitted the request will use the global agent (as long as your options allow for it). Otherwise, request will search the pool for your custom agent. If no custom agent is found, a new agent will be created and added to the pool. **Note:**`pool` is used only when the `agent` option is not specified.
- A `maxSockets` property can also be provided on the `pool` object to set the max number of sockets for all agents created (ex: `pool: {maxSockets: Infinity}`).
- Note that if you are sending multiple requests in a loop and creating
-`localAddress` - Local interface to bind for network connections.
-`proxy` - An HTTP proxy to be used. Supports proxy Auth with Basic Auth, identical to support for the `url` parameter (by embedding the auth info in the `uri`)
-`strictSSL` - If `true`, requires SSL certificates be valid. **Note:** to use your own certificate authority, you need to specify an agent that was created with that CA as an option.
-`time` - If `true`, the request-response cycle (including all redirects) is timed at millisecond resolution, and the result provided on the response's `elapsedTime` property.
-`har` - A [HAR 1.2 Request Object](http://www.softwareishard.com/blog/har-12-spec/#request), will be processed from HAR format into options overwriting matching values *(see the [HAR 1.2 section](#support-for-har-1.2) for details)*
Cookies are disabled by default (else, they would be used in subsequent requests). To enable cookies, set `jar` to `true` (either in `defaults` or `options`) and install `tough-cookie`.