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    stream_notification_callback

    (PHP 5 >= 5.2.0, PHP 7, PHP 8)

    stream_notification_callback — A callback function for the notification context parameter

    Description

    stream_notification_callback(
        int $notification_code,
        int $severity,
        ?string $message,
        int $message_code,
        int $bytes_transferred,
        int $bytes_max
    ): void

    A callable function, used by the notification context parameter, called during an event.

    Note:

    This is not a real function, only a prototype of how the function should be.

    Parameters

    notification_code

    One of the STREAM_NOTIFY_* notification constants.

    severity

    One of the STREAM_NOTIFY_SEVERITY_* notification constants.

    message

    Passed if a descriptive message is available for the event.

    message_code

    Passed if a descriptive message code is available for the event.

    The meaning of this value is dependent on the specific wrapper in use.

    bytes_transferred

    If applicable, the bytes_transferred will be populated.

    bytes_max

    If applicable, the bytes_max will be populated.

    Return Values

    No value is returned.

    Changelog

    Version Description
    8.3.0 Support for STREAM_NOTIFY_COMPLETED implemented, earlier PHP versions would never trigger this notification.

    Examples

    Example #1 stream_notification_callback() example

    <?php
    function stream_notification_callback($notification_code, $severity, $message, $message_code, $bytes_transferred, $bytes_max) {

    switch(    $notification_code) {
    case     STREAM_NOTIFY_RESOLVE:
    case     STREAM_NOTIFY_AUTH_REQUIRED:
    case     STREAM_NOTIFY_COMPLETED:
    case     STREAM_NOTIFY_FAILURE:
    case     STREAM_NOTIFY_AUTH_RESULT:
    var_dump($notification_code, $severity, $message, $message_code, $bytes_transferred, $bytes_max);
    /* Ignore */
    break;

    case     STREAM_NOTIFY_REDIRECTED:
    echo     "Being redirected to: ", $message;
    break;

    case     STREAM_NOTIFY_CONNECT:
    echo     "Connected...";
    break;

    case     STREAM_NOTIFY_FILE_SIZE_IS:
    echo     "Got the filesize: ", $bytes_max;
    break;

    case     STREAM_NOTIFY_MIME_TYPE_IS:
    echo     "Found the mime-type: ", $message;
    break;

    case     STREAM_NOTIFY_PROGRESS:
    echo     "Made some progress, downloaded ", $bytes_transferred, " so far";
    break;
    }
    echo     "\n";
    }

    $ctx = stream_context_create();
    stream_context_set_params($ctx, array("notification" => "stream_notification_callback"));

    file_get_contents("http://php.net/contact", false, $ctx);
    ?>

    The above example will output something similar to:

    Connected...
Found the mime-type: text/html; charset=utf-8
Being redirected to: http://no.php.net/contact
Connected...
Got the filesize: 0
Found the mime-type: text/html; charset=utf-8
Being redirected to: http://no.php.net/contact.php
Connected...
Got the filesize: 4589
Found the mime-type: text/html;charset=utf-8
Made some progress, downloaded 0 so far
Made some progress, downloaded 0 so far
Made some progress, downloaded 0 so far
Made some progress, downloaded 1440 so far
Made some progress, downloaded 2880 so far
Made some progress, downloaded 4320 so far
Made some progress, downloaded 5760 so far
Made some progress, downloaded 6381 so far
Made some progress, downloaded 7002 so far

    Example #2 Simple progressbar for commandline download client

    <?php
    function usage($argv) {
    echo     "Usage:\n";
    printf("\tphp %s <http://example.com/file> <localfile>\n", $argv[0]);
    exit(    1);
    }

    function     stream_notification_callback($notification_code, $severity, $message, $message_code, $bytes_transferred, $bytes_max) {
    static     $filesize = null;

    switch(    $notification_code) {
    case     STREAM_NOTIFY_RESOLVE:
    case     STREAM_NOTIFY_AUTH_REQUIRED:
    case     STREAM_NOTIFY_COMPLETED:
    case     STREAM_NOTIFY_FAILURE:
    case     STREAM_NOTIFY_AUTH_RESULT:
    /* Ignore */
    break;

    case     STREAM_NOTIFY_REDIRECTED:
    echo     "Being redirected to: ", $message, "\n";
    break;

    case     STREAM_NOTIFY_CONNECT:
    echo     "Connected...\n";
    break;

    case     STREAM_NOTIFY_FILE_SIZE_IS:
    $filesize = $bytes_max;
    echo     "Filesize: ", $filesize, "\n";
    break;

    case     STREAM_NOTIFY_MIME_TYPE_IS:
    echo     "Mime-type: ", $message, "\n";
    break;

    case     STREAM_NOTIFY_PROGRESS:
    if (    $bytes_transferred > 0) {
    if (!isset(    $filesize)) {
    printf("\rUnknown filesize.. %2d kb done..", $bytes_transferred/1024);
    } else {
    $length = (int) (($bytes_transferred/$filesize)*100);
    printf("\r[%-100s] %d%% (%2d/%2d kb)", str_repeat("=", $length). ">", $length, ($bytes_transferred/1024), $filesize/1024);
    }
    }
    break;
    }
    }

    isset(    $argv[1], $argv[2]) or usage($argv);

    $ctx = stream_context_create();
    stream_context_set_params($ctx, array("notification" => "stream_notification_callback"));

    $fp = fopen($argv[1], "r", false, $ctx);
    if (    is_resource($fp) && file_put_contents($argv[2], $fp)) {
    echo     "\nDone!\n";
    exit(    0);
    }

    $err = error_get_last();
    echo     "\nErrrrrorr..\n", $err["message"], "\n";
    exit(    1);
    ?>

    Executing the example above with: php -n fetch.php http://no2.php.net/get/php-5-LATEST.tar.bz2/from/this/mirror php-latest.tar.bz2 will output something similar too: 

    Connected...
Mime-type: text/html; charset=utf-8
Being redirected to: http://no2.php.net/distributions/php-5.2.5.tar.bz2
Connected...
Filesize: 7773024
Mime-type: application/octet-stream
[========================================>                                                           ] 40% (3076/7590 kb)

    Found A Problem?

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    User Contributed Notes 2 notes

    up
    2
    billynoah at gmail dot com
    7 years ago
    A couple of notes regarding the examples here (I'm using PHP 7.0.18):

    1) fopen() did not provide STREAM_NOTIFY_PROGRESS for me but `file_get_contents()` worked fine.

    2) The bytes transferred when transferring a zip file seems to always be shy by 8192 (8k). This varies depending on filetype and also breaks STREAM_NOTIFY_PROGRESS when the filesize is below 8k. I modified the function and it's now displaying the correct amount transferred and percentage downloaded on zip files above 8k. I'm not sure why the callback is so inconsistent but hopefully this is helpful to someone. This was also modified to only display progress:

    <?php

    $ctx     = stream_context_create();
    stream_context_set_params($ctx, array("notification" => "stream_notification_callback"));
    $fileData = @file_get_contents('http://example.com/test.zip',false,$ctx);

    function     stream_notification_callback($notification_code, $severity, $message, $message_code, $bytes_transferred, $bytes_max) {
    static     $filesize = null;
    switch(    $notification_code) {
    case     STREAM_NOTIFY_FILE_SIZE_IS:
    $filesize = $bytes_max;
    break;
    case     STREAM_NOTIFY_CONNECT:
    echo     "Connected...\n";
    break;
    case     STREAM_NOTIFY_PROGRESS:
    if (    $bytes_transferred > 0 && $filesize >= 8192) {
    $bytes_transferred += 8192;
    if (!isset(    $filesize)) {
    printf("\rUnknown filesize.. %2d kb done..", $bytes_transferred/1024);
    } else {
    $length = (int)(($bytes_transferred/$filesize)*100);
    printf("\r[%-100s] %d%% (%2d/%2d kb)", str_repeat("=", $length). ">", $length, ($bytes_transferred/1024), $filesize/1024);
    }
    }
    break;
    }
    }
    ?>
    up
    1
    aetonsi
    2 years ago
    A couple of unreported behaviors:
    - case 1) if this callback calls die/exit($msg), it will print $msg, then the execution will go on until the request/wrapper is consumed, emitting a "PHP Warning: Failed to call user notifier" on each invocation of the callback. After the last callback invocation, the script is immediately terminated.
    - case 2) if this callback throws an exception, it will behave the same way as exit/die, except for the fact that after the last callback invocation it does not terminate the script. The exception is instead raised in the scope of the request/wrapper, and can be caught with a try catch (right there or at a higher level).

    Example code for case 1). The final "TEST ECHO" string will NOT be printed.
    <?php
    $context     = stream_context_create(['http' => ['ignore_errors' => true,]]);
    stream_context_set_params($context, ['notification' => function () {
    die(    'error');
    }]);

    file_get_contents('https://www.google.com', false, $context);
    echo     "TEST ECHO";
    ?>

    Example code for case 2). The exception is raised at the level of the file_get_contents call, it's catched, and the final "TEST ECHO" gets printed.
    <?php
    $context     = stream_context_create(['http' => ['ignore_errors' => true,]]);
    stream_context_set_params($context, ['notification' => function () {
    throw new     Exception('...');
    }]);

    try{
    file_get_contents('https://www.google.com', false, $context);
    }catch(    exception $e) { }
    echo     "TEST ECHO";
    ?>
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