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 array 或 string

请求期间发送的附加 header 。此选项中的值将覆盖其他值（如 User-agent:， Host: 和 Authentication:)，即使在执行 Location: 重定向时也是如此。所以，如果启用了 follow_location 就不建议设置 Host: header。

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 bool

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 int

跟随 Location header 的重定向。设置为 0 以禁用。

默认值是 1。

max_redirects int

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。

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 bool

即使是故障状态码依然获取内容。

默认值为 false.

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 Permanently',
    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).

参见

User Contributed Notes

ASchmidt at Anamera dot net 16-Feb-2021 02:51


With the default of 



    'follow_location'   =>  1



be certain NEVER include a "Host:" header in the 'header' array.



If the host is set to "mydomain.com", and that web site has a (quite common) redirect to "www.mydomain.com", then the initial request to "http://mydomain.com" will get the expected response of:



HTTP/1.1 301 Moved Permanently

Location: http://www.mydomain.com/



However, the follow-up request does NOT replace the original "host" header with the new "location" value, as one would expect. Consequently each "follow-location" request will again be served by the original host of "http://mydomain.com", and continue the redirect loop until 'max_redirects' has been exhausted.



(For details: https://bugs.php.net/bug.php?id=77889)

daniel.peder (a) gmail.com 16-Oct-2017 06:55


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 16-Oct-2017 06:50


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 02:50


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 08:39


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 01:32


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 03:19


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 06:14


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 01:41


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 18-Jan-2011 08:09


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.