<?php
/**
* Generates a Photon URL.
*
* @see http://developer.wordpress.com/docs/photon/
*
* @param string $image_url URL to the publicly accessible image you want to manipulate
* @param array|string $args An array of arguments, i.e. array( 'w' => '300', 'resize' => array( 123, 456 ) ), or in string form (w=123&h=456)
* @return string The raw final URL. You should run this through esc_url() before displaying it.
*/
function jetpack_photon_url( $image_url, $args = array(), $scheme = null ) {
$image_url = trim( $image_url );
/**
* Allow specific image URls to avoid going through Photon.
*
* @since 3.2.0
*
* @param bool false Should the image be returned as is, without going through Photon. Default to false.
* @param string $image_url Image URL.
* @param array|string $args Array of Photon arguments.
* @param string|null $scheme Image scheme. Default to null.
*/
if ( false !== apply_filters( 'jetpack_photon_skip_for_url', false, $image_url, $args, $scheme ) ) {
return $image_url;
}
/**
* Filter the original image URL before it goes through Photon.
*
* @since 1.9.0
*
* @param string $image_url Image URL.
* @param array|string $args Array of Photon arguments.
* @param string|null $scheme Image scheme. Default to null.
*/
$image_url = apply_filters( 'jetpack_photon_pre_image_url', $image_url, $args, $scheme );
/**
* Filter the original Photon image parameters before Photon is applied to an image.
*
* @since 1.9.0
*
* @param array|string $args Array of Photon arguments.
* @param string $image_url Image URL.
* @param string|null $scheme Image scheme. Default to null.
*/
$args = apply_filters( 'jetpack_photon_pre_args', $args, $image_url, $scheme );
if ( empty( $image_url ) )
return $image_url;
$image_url_parts = @parse_url( $image_url );
// Unable to parse
if ( ! is_array( $image_url_parts ) || empty( $image_url_parts['host'] ) || empty( $image_url_parts['path'] ) )
return $image_url;
if ( is_array( $args ) ){
// Convert values that are arrays into strings
foreach ( $args as $arg => $value ) {
if ( is_array( $value ) ) {
$args[$arg] = implode( ',', $value );
}
}
// Encode values
// See http://core.trac.wordpress.org/ticket/17923
$args = rawurlencode_deep( $args );
}
/** This filter is documented below. */
$custom_photon_url = apply_filters( 'jetpack_photon_domain', '', $image_url );
$custom_photon_url = esc_url( $custom_photon_url );
// You can't run a Photon URL through Photon again because query strings are stripped.
// So if the image is already a Photon URL, append the new arguments to the existing URL.
if (
in_array( $image_url_parts['host'], array( 'i0.wp.com', 'i1.wp.com', 'i2.wp.com' ) )
|| $image_url_parts['host'] === parse_url( $custom_photon_url, PHP_URL_HOST )
) {
$photon_url = add_query_arg( $args, $image_url );
return jetpack_photon_url_scheme( $photon_url, $scheme );
}
/**
* Allow Photon to use query strings as well.
* By default, Photon doesn't support query strings so we ignore them and look only at the path.
* This setting is Photon Server dependent.
*
* @since 1.9.0
*
* @param bool false Should images using query strings go through Photon. Default is false.
* @param string $image_url_parts['host'] Image URL's host.
*/
if ( ! apply_filters( 'jetpack_photon_any_extension_for_domain', false, $image_url_parts['host'] ) ) {
// Photon doesn't support query strings so we ignore them and look only at the path.
// However some source images are served via PHP so check the no-query-string extension.
// For future proofing, this is a blacklist of common issues rather than a whitelist.
$extension = pathinfo( $image_url_parts['path'], PATHINFO_EXTENSION );
if ( empty( $extension ) || in_array( $extension, array( 'php' ) ) )
return $image_url;
}
$image_host_path = $image_url_parts['host'] . $image_url_parts['path'];
// Figure out which CDN subdomain to use
srand( crc32( $image_host_path ) );
$subdomain = rand( 0, 2 );
srand();
/**
* Filters the domain used by the Photon module.
*
* @since 3.4.2
*
* @param string http://i{$subdomain}.wp.com Domain used by Photon. $subdomain is a random number between 0 and 2.
* @param string $image_url URL of the image to be photonized.
*/
$photon_domain = apply_filters( 'jetpack_photon_domain', "http://i{$subdomain}.wp.com", $image_url );
$photon_domain = trailingslashit( esc_url( $photon_domain ) );
$photon_url = $photon_domain . $image_host_path;
/**
* Add query strings to Photon URL.
* By default, Photon doesn't support query strings so we ignore them.
* This setting is Photon Server dependent.
*
* @since 1.9.0
*
* @param bool false Should query strings be added to the image URL. Default is false.
* @param string $image_url_parts['host'] Image URL's host.
*/
if ( isset( $image_url_parts['query'] ) && apply_filters( 'jetpack_photon_add_query_string_to_domain', false, $image_url_parts['host'] ) ) {
$photon_url .= '?q=' . rawurlencode( $image_url_parts['query'] );
}
if ( $args ) {
if ( is_array( $args ) ) {
$photon_url = add_query_arg( $args, $photon_url );
} else {
// You can pass a query string for complicated requests but where you still want CDN subdomain help, etc.
$photon_url .= '?' . $args;
}
}
return jetpack_photon_url_scheme( $photon_url, $scheme );
}
add_filter( 'jetpack_photon_url', 'jetpack_photon_url', 10, 3 );
/**
* WordPress.com
*
* If a cropped WP.com-hosted image is the source image, have Photon replicate the crop.
*/
add_filter( 'jetpack_photon_pre_args', 'jetpack_photon_parse_wpcom_query_args', 10, 2 );
function jetpack_photon_parse_wpcom_query_args( $args, $image_url ) {
$parsed_url = @parse_url( $image_url );
if ( ! $parsed_url )
return $args;
$image_url_parts = wp_parse_args( $parsed_url, array(
'host' => '',
'query' => ''
) );
if ( '.files.wordpress.com' != substr( $image_url_parts['host'], -20 ) )
return $args;
if ( empty( $image_url_parts['query'] ) )
return $args;
$wpcom_args = wp_parse_args( $image_url_parts['query'] );
if ( empty( $wpcom_args['w'] ) || empty( $wpcom_args['h'] ) )
return $args;
// Keep the crop by using "resize"
if ( ! empty( $wpcom_args['crop'] ) ) {
if ( is_array( $args ) ) {
$args = array_merge( array( 'resize' => array( $wpcom_args['w'], $wpcom_args['h'] ) ), $args );
} else {
$args = 'resize=' . rawurlencode( absint( $wpcom_args['w'] ) . ',' . absint( $wpcom_args['h'] ) ) . '&' . $args;
}
} else {
if ( is_array( $args ) ) {
$args = array_merge( array( 'fit' => array( $wpcom_args['w'], $wpcom_args['h'] ) ), $args );
} else {
$args = 'fit=' . rawurlencode( absint( $wpcom_args['w'] ) . ',' . absint( $wpcom_args['h'] ) ) . '&' . $args;
}
}
return $args;
}
/**
* Facebook
*/
add_filter( 'jetpack_photon_add_query_string_to_domain', 'jetpack_photon_allow_facebook_graph_domain', 10, 2 );
add_filter( 'jetpack_photon_any_extension_for_domain', 'jetpack_photon_allow_facebook_graph_domain', 10, 2 );
function jetpack_photon_url_scheme( $url, $scheme ) {
if ( ! in_array( $scheme, array( 'http', 'https', 'network_path' ) ) ) {
$scheme = is_ssl() ? 'https' : 'http';
}
if ( 'network_path' == $scheme ) {
$scheme_slashes = '//';
} else {
$scheme_slashes = "$scheme://";
}
return preg_replace( '#^[a-z:]+//#i', $scheme_slashes, $url );
}
function jetpack_photon_allow_facebook_graph_domain( $allow = false, $domain ) {
switch ( $domain ) {
case 'graph.facebook.com' :
return true;
}
return $allow;
}
add_filter( 'jetpack_photon_skip_for_url', 'jetpack_photon_banned_domains', 9, 4 );
function jetpack_photon_banned_domains( $skip, $image_url, $args, $scheme ) {
$banned_domains = array(
'http://chart.googleapis.com/',
'https://chart.googleapis.com/',
'http://chart.apis.google.com/',
);
foreach ( $banned_domains as $banned_domain ) {
if ( wp_startswith( $image_url, $banned_domain ) )
return true;
}
return $skip;
}