http:// -- https:// — Accessing HTTP(s) URLs
Allows read-only access to files/resources via HTTP 1.0, using the HTTP GET method. A Host: header is sent with the request to handle name-based virtual hosts. If you have configured a user_agent string using your php.ini file or the stream context, it will also be included in the request.
The stream allows access to the body of the resource; the headers are stored in the $http_response_header variable.
If it's important to know the URL of the resource where your document came from (after all redirects have been processed), you'll need to process the series of response headers returned by the stream.
The from directive will be used for the From: header if set and not overwritten by the Context options and parameters.
| 版本 | 说明 |
|---|---|
| 4.3.7 | Detect buggy IIS servers to avoid "SSL: Fatal Protocol Error" errors. |
| 4.3.0 | Added https://. |
| 4.0.5 | Added support for redirects. |
Example #1 Detecting which URL we ended up on after redirects
<?php
$url = 'http://www.example.com/redirecting_page.php';
$fp = fopen($url, 'r');
$meta_data = stream_get_meta_data($fp);
foreach ($meta_data['wrapper_data'] as $response) {
/* Were we redirected? */
if (strtolower(substr($response, 0, 10)) == 'location: ') {
/* update $url with where we were redirected to */
$url = substr($response, 10);
}
}
?>
Example #2 Sending custom headers with an HTTP request
Custom headers may be sent using context options. It is also possible to use this hack: Custom headers may be sent with an HTTP request by taking advantage of a side-effect in the handling of the user_agent INI setting. Set user_agent to any valid string (such as the default PHP/version setting) followed by a carriage-return/line-feed pair and any additional headers.
<?php
ini_set('user_agent', "PHP\r\nX-MyCustomHeader: Foo");
$fp = fopen('http://www.example.com/index.php', 'r');
?>
Results in the following request being sent:
GET /index.php HTTP/1.0 Host: www.example.com User-Agent: PHP X-MyCustomHeader: Foo
Note: HTTPS is only supported when the openssl extension is enabled.
HTTP connections are read-only; writing data or copying files to an HTTP resource is not supported.
Sending POST and PUT requests, for example, can be done with the help of HTTP Contexts.