apache_request_headers() is not visible in PHP CLI

[HeenaBansal20]

Description

I am building PHP from source and running php script on cli.
Trying to use apache_request_headers() , apache_response_headers() or getallheaders() functions are not available in my php script.
Fatal error: Uncaught Error: Call to undefined function apache_request_headers()

PHp Script

  http_cli_server_start(__DIR__ . '/get_headers.inc');
    $ctx = stream_context_create(array('http' => array('method' => 'POST', 'content' => 'foo', 'header' => array('Content-Type: text/html', 'Header1:Value1'))));
    $content = @file_get_contents("http://localhost:" . PHP_HTTP_SERVER_PORT, false, $ctx);
    $headers=apache_request_headers();
    

get_headers.inc is just a script which starts php executable with cmd

cmd = "exec {$php_executable} -t {$doc_root} -n $serverArgs -S " . PHP_HTTP_SERVER_ADDRESS;
    $cmd .= " {$router}";
    $cmd .= " 2>/dev/null";
    $cmd .= " 1>/dev/null";

    $handle = proc_open($cmd, $descriptorspec, $pipes, $doc_root);

As per docs, it claims it works in the Apache, FastCGI, CLI, and FPM webservers.

PHP Version

PHP 8.1

Operating System

Ubuntu22

[damianwadley]

and running php script on cli.

apache_request_headers and such aren't available in the regular CLI. They are available when the script is running through the CLI server, such as the one being set up in your get_headers script.
So you can't use them from the CLI (as in php your-script.php) like that.

Additionally, I think you're misunderstanding what the function does. It returns the headers from the current request - not from a request that happened through http(s):// and a function like file_get_contents. Meaning it returns the same sort of information you can get through the list of headers in $_SERVER.

All in all, I'm not even sure what the code you posted is attempting to do.

[HeenaBansal20]

@damianwadley , Thanks for quick response.
I am actually looking out ways to understand , how I can send customize headers to a request or a response and how I can confirm if the headers are available in my request /response.

I see that ctx option can be used to add the custom headers in your stream.
I am trying to make an http call using that stream context which I created with my custom headers.
DO you think the above script is not actually doing that.

[damianwadley]

The part about sending request headers looks correct to me.

If you want to verify that you're sending the request correctly. you can use $_SERVER or apache_request_headers in the code that's run by the server.

Starting the built-in server:

<?php // debug.php

echo "This is output from the debug script\n";
print_r(apache_request_headers());

php -S localhost:80 -t .

Testing the request:

<?php // request.php

$ctx = stream_context_create(array('http' => array('method' => 'POST', 'content' => 'foo', 'header' => array('Content-Type: text/html', 'Header1:Value1'))));
$content = @file_get_contents('http://localhost/debug.php', false, $ctx);
print_r($content);

php request.php