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function is not described

WP_HTTP_Proxy::send_through_proxy() public WP 2.8.0

Determines whether the request should be sent through a proxy.

We want to keep localhost and the site URL from being sent through the proxy, because some proxies can not handle this. We also have the constant available for defining other hosts that won't be sent through the proxy.

{} It's a method of the class: WP_HTTP_Proxy{}

Hooks from the method
Return

true/false. Whether to send the request through the proxy.

Usage

$WP_HTTP_Proxy = new WP_HTTP_Proxy();
$WP_HTTP_Proxy->send_through_proxy( $uri );
$uri(string) (required)
URL of the request.

Changelog

Since 2.8.0 Introduced.

Code of WP_HTTP_Proxy::send_through_proxy() WP 5.5.2

<?php
public function send_through_proxy( $uri ) {
	$check = parse_url( $uri );

	// Malformed URL, can not process, but this could mean ssl, so let through anyway.
	if ( false === $check ) {
		return true;
	}

	$home = parse_url( get_option( 'siteurl' ) );

	/**
	 * Filters whether to preempt sending the request through the proxy.
	 *
	 * Returning false will bypass the proxy; returning true will send
	 * the request through the proxy. Returning null bypasses the filter.
	 *
	 * @since 3.5.0
	 *
	 * @param bool|null $override Whether to send the request through the proxy. Default null.
	 * @param string    $uri      URL of the request.
	 * @param array     $check    Associative array result of parsing the request URL with `parse_url()`.
	 * @param array     $home     Associative array result of parsing the site URL with `parse_url()`.
	 */
	$result = apply_filters( 'pre_http_send_through_proxy', null, $uri, $check, $home );
	if ( ! is_null( $result ) ) {
		return $result;
	}

	if ( 'localhost' === $check['host'] || ( isset( $home['host'] ) && $home['host'] === $check['host'] ) ) {
		return false;
	}

	if ( ! defined( 'WP_PROXY_BYPASS_HOSTS' ) ) {
		return true;
	}

	static $bypass_hosts   = null;
	static $wildcard_regex = array();
	if ( null === $bypass_hosts ) {
		$bypass_hosts = preg_split( '|,\s*|', WP_PROXY_BYPASS_HOSTS );

		if ( false !== strpos( WP_PROXY_BYPASS_HOSTS, '*' ) ) {
			$wildcard_regex = array();
			foreach ( $bypass_hosts as $host ) {
				$wildcard_regex[] = str_replace( '\*', '.+', preg_quote( $host, '/' ) );
			}
			$wildcard_regex = '/^(' . implode( '|', $wildcard_regex ) . ')$/i';
		}
	}

	if ( ! empty( $wildcard_regex ) ) {
		return ! preg_match( $wildcard_regex, $check['host'] );
	} else {
		return ! in_array( $check['host'], $bypass_hosts, true );
	}
}