HTTP context 选项

HTTP context 选项 — HTTP context 的选项列表

说明

提供给 http:// 和 https:// 传输协议的 context 选项。 transports.

可选项

method string

远程服务器支持的 GET，POST 或其它 HTTP 方法。

默认值是 GET。

header string

请求期间发送的额外 header 。在此选项的值将覆盖其他值 （诸如 User-agent:， Host: 和 Authentication:）。

user_agent string

要发送的 header User-Agent: 的值。如果在上面的 header context 选项中没有指定 user-agent，此值将被使用。

默认使用 php.ini 中设置的 user_agent。

content string

在 header 后面要发送的额外数据。通常使用POST或PUT请求。

proxy string

URI 指定的代理服务器的地址。(e.g. tcp://proxy.example.com:5100).

request_fulluri boolean

当设置为 TRUE 时，在构建请求时将使用整个 URI 。(i.e. GET http://www.example.com/path/to/file.html HTTP/1.0)。 虽然这是一个非标准的请求格式，但某些代理服务器需要它。

默认值是 FALSE.

follow_location integer

跟随 Location header 的重定向。设置为 0 以禁用。

默认值是 1。

max_redirects integer

跟随重定向的最大次数。值为 1 或更少则意味不跟随重定向。

默认值是 20。

protocol_version float

HTTP 协议版本。

默认值是 1.0。

Note:

PHP 5.3.0 以前的版本没有实现分块传输解码。 如果此值设置为 1.1 ，与 1.1 的兼容将是你的责任。

timeout float

读取超时时间，单位为秒（s），用 float 指定(e.g. 10.5)。

默认使用 php.ini 中设置的 default_socket_timeout。

ignore_errors boolean

即使是故障状态码依然获取内容。

默认值为 FALSE.

更新日志

版本 说明
5.3.4 添加 follow_location。
5.3.0 当 protocol_version 设置为 1.1 时支持分块传输解码。
5.2.10 添加 ignore_errors。
5.2.10 header 现在可以是一个数字索引的 array。
5.2.1 添加 timeout。
5.1.0 Added HTTPS proxying through HTTP proxies. 添加经由 HTTP 代理的 HTTPS 代理。
5.1.0 添加 max_redirects。
5.1.0 添加 protocol_version。

范例

Example #1 获取一个页面并发送 POST 数据

<?php

$postdata = http_build_query(
    array(
        'var1' => 'some content',
        'var2' => 'doh'
    )
);

$opts = array('http' =>
    array(
        'method'  => 'POST',
        'header'  => 'Content-type: application/x-www-form-urlencoded',
        'content' => $postdata
    )
);

$context = stream_context_create($opts);

$result = file_get_contents('http://example.com/submit.php', false, $context);

?>

Example #2 忽略重定向并获取 header 和内容

<?php

$url = "http://www.example.org/header.php";

$opts = array('http' =>
    array(
        'method' => 'GET',
        'max_redirects' => '0',
        'ignore_errors' => '1'
    )
);

$context = stream_context_create($opts);
$stream = fopen($url, 'r', false, $context);

// header information as well as meta data
// about the stream
var_dump(stream_get_meta_data($stream));

// actual data at $url
var_dump(stream_get_contents($stream));
fclose($stream);
?>

注释

Note: Underlying socket stream context options
Additional context options may be supported by the underlying transport For http:// streams, refer to context options for the tcp:// transport. For https:// streams, refer to context options for the ssl:// transport.

Note: HTTP status line
When this stream wrapper follows a redirect, the wrapper_data returned by stream_get_meta_data() might not necessarily contain the HTTP status line that actually applies to the content data at index 0. 

array (
  'wrapper_data' =>
  array (
    0 => 'HTTP/1.0 301 Moved Permantenly',
    1 => 'Cache-Control: no-cache',
    2 => 'Connection: close',
    3 => 'Location: http://example.com/foo.jpg',
    4 => 'HTTP/1.1 200 OK',
    ...
The first request returned a 301 (permanent redirect), so the stream wrapper automatically followed the redirect to get a 200 response (index = 4).

User Contributed Notes

daniel.peder (a) gmail.com 17-Oct-2017 03:55
note that both http and https transports require the same context name http

// OK example:
// this will work as expected
// note the url with https but context with http
$correct_data = file_get_contents('https://example.com', false, stream_context_create(array('http' => array(...))));

// INVALID example:
// this will not work, the context will be ignored
// note the url with https also context with https
$correct_data = file_get_contents('https://example.com', false, stream_context_create(array('https' => array(...))));
daniel dot peder at gmail dot com 17-Oct-2017 03:50
note that for both http and https protocols require the same 'http' context keyword:

<?php

// CORRECT example:
// this will work as expected
// note the url with https but context with http
$correct_data = file_get_contents('https://example.com', false, stream_context_create(array('http' => array(...))));

// INVALID example:
// this will not work, the context will be ignored
// note the url with https also context with https
$correct_data = file_get_contents('https://example.com', false, stream_context_create(array('https' => array(...))));
aruntechguy at outlook dot com 22-Sep-2017 11:50
If you want to use Basic Auth while using get_headers(), use stream_context options below.

I am using HEAD method here, but please feel free to use GET also.

<?php
$targetUrl = 'http or https target url here';
$basicAuth = base64_encode('username:password');

stream_context_set_default(
    [
        'http' => [
            'method' => 'HEAD',
            'header' => 'Authorization: Basic ' . $basicAuth
        ]
    ]
);
$result = get_headers($targetUrl);

print_r($result);
ywarnier at beeznest dot org 02-Aug-2017 05:39
Note that setting request_fulluri to true will *change* the value of $_SERVER['REQUEST_URI] on the receiving end (from /abc.php to http://domain.com/abc.php).
jay 14-Apr-2015 10:32
Remember to match content with Content-type:

<?php

$data = array(
    'var1' => 'some content',
    'var2' => 'doh'
);

$opts = array('http' =>
    array(
        'method'  => 'POST',
        'header'  => 'Content-type: application/json',  // here...
        'content' => json_encode($data)  // and here.
    )
);

. . .

?>
nate 17-Apr-2014 12:19
Note that if you set the protocol_version option to 1.1 and the server you are requesting from is configured to use keep-alive connections, the function (fopen, file_get_contents, etc.) will "be slow" and take a long time to complete. This is a feature of the HTTP 1.1 protocol you are unlikely to use with stream contexts in PHP.

Simply add a "Connection: close" header to the request to eliminate the keep-alive timeout:

<?php
// php 5.4 : array syntax and header option with array value
$data = file_get_contents('http://www.example.com/', null, stream_context_create([
    'http' => [
        'protocol_version' => 1.1,
        'header'           => [
            'Connection: close',
        ],
    ],
]));
?>
chris 06-Feb-2014 03:14
I had quite a bit of trouble trying to make a request with fopen through a proxy to a secure url.  I kept getting a 400 Bad Request back from the remote host.  It was receiving the proxy url as the SNI host.  In order to get around this I had to explicity set the SNI host to the domain I was trying to reach.  It's apparently the issue outlined in this bug:

https://bugs.php.net/bug.php?id=63519

<?php
$domain = parse_url($file, PHP_URL_HOST);
$proxy_string = "tcp://" . WP_PROXY_HOST  . ":" . WP_PROXY_PORT;
$opts = array(
    'http' => array( 'proxy' => $proxy_string ),
    'ssl' => array( 'SNI_enabled' => true, 'SNI_server_name' => $domain));
$context = stream_context_create($opts);
$handle = fopen( $file, 'r', false, $context );
?>
vchampion at gmail dot com 23-Oct-2012 10:41
If you use the proxy server and encounter an error "fopen(http://example.com): failed to open stream: HTTP request failed! HTTP/1.0 400 Bad Request" note that in many situations you need also set the parameter "request_fulluri" to "true" in your stream options. Without this option the php script sends the empty request to the server as "GET / HTTP/0.0" and the proxy server replies to it with the "HTTP 400" error.

For example (working sample):
<?php
$stream = stream_context_create(Array("http" => Array("method"  => "GET",
                                                      "timeout" => 20,
                                                      "header"  => "User-agent: Myagent",
                                                      "proxy"   => "tcp://my-proxy.localnet:3128",
                                                      'request_fulluri' => True /* without this option we get an HTTP error! */
                                )));

if ( $fp = fopen("http://example.com", 'r', false, $stream) ) {
    print "well done";
}
?>

P>S> PHP 5.3.17
gourav sarkar 19-Jan-2011 05:09
watch your case when using methods (POST and GET)...it must be always uppercase. in case of you write it in lower case it wont work.