AMP - the homepage's cache isn't cleared when publishing posts

[vmanthos]

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Describe the bug

When the official AMP plugin is used, publishing a new post won't clear the cache of the AMP homepage, the way we do for the non-AMP homepage:
https://example.com/?amp=1

This is because rocket_clean_home() doesn't have the necessary logic built-in:

wp-rocket/inc/functions/files.php

Lines 576 to 659 in 0275715

	/**
	* Remove the home cache file and pagination
	*
	* $since 2.2 Add $lang argument
	*
	* @since 2.0 Delete cache files for all users
	* @since 1.0
	*
	* @param string $lang (default: '') The language code.
	* @return void
	*/
	function rocket_clean_home( $lang = '' ) {
	$parse_url = get_rocket_parse_url( get_rocket_i18n_home_url( $lang ) );
	/** This filter is documented in inc/front/htaccess.php */
	if ( apply_filters( 'rocket_url_no_dots', false ) ) {
	$parse_url['host'] = str_replace( '.', '_', $parse_url['host'] );
	}
	$root = WP_ROCKET_CACHE_PATH . $parse_url['host'] . '*' . untrailingslashit( $parse_url['path'] );
	/**
	* Filter the homepage caching folder root
	*
	* @since 2.6.5
	* @param array $root The root that will be returned.
	* @param string $host The website host.
	* @param string $path The website path.
	*/
	$root = apply_filters( 'rocket_clean_home_root', $root, $parse_url['host'], $parse_url['path'] );
	/**
	* Fires before the home cache file is deleted
	*
	* @since 1.0
	*
	* @param string $root The path of home cache file.
	* @param string $lang The current lang to purge.
	*/
	do_action( 'before_rocket_clean_home', $root, $lang ); // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals
	// Delete homepage.
	$files = glob( $root . '/{index,index-*}.{html,html_gzip}', GLOB_BRACE | GLOB_NOSORT );
	if ( $files ) {
	foreach ( $files as $file ) { // no array map to use @.
	rocket_direct_filesystem()->delete( $file );
	}
	}
	// Delete homepage pagination.
	$dirs = glob( $root . '*/' . $GLOBALS['wp_rewrite']->pagination_base, GLOB_NOSORT );
	if ( $dirs ) {
	foreach ( $dirs as $dir ) {
	rocket_rrmdir( $dir );
	}
	}
	// Remove the hidden empty file for mobile detection on NGINX with the Rocket NGINX configuration.
	$nginx_mobile_detect_files = glob( $root . '/.mobile-active', GLOB_BRACE | GLOB_NOSORT );
	if ( $nginx_mobile_detect_files ) {
	foreach ( $nginx_mobile_detect_files as $nginx_mobile_detect_file ) { // no array map to use @.
	rocket_direct_filesystem()->delete( $nginx_mobile_detect_file );
	}
	}
	// Remove the hidden empty file for webp.
	$nowebp_detect_files = glob( $root . '/.no-webp', GLOB_BRACE | GLOB_NOSORT );
	if ( $nowebp_detect_files ) {
	foreach ( $nowebp_detect_files as $nowebp_detect_file ) { // no array map to use @.
	rocket_direct_filesystem()->delete( $nowebp_detect_file );
	}
	}
	/**
	* Fires after the home cache file was deleted
	*
	* @since 1.0
	*
	* @param string $root The path of home cache file.
	* @param string $lang The current lang to purge.
	*/
	do_action( 'after_rocket_clean_home', $root, $lang ); // phpcs:ignore WordPress.NamingConventions.PrefixAllGlobals
	}

To Reproduce
Steps to reproduce the behavior:

1. Install/activate the AMP plugin
2. Visit the homepage using a mobile emulator, and make sure that's cache.
3. Publish a new post.
4. The content in the /#amp=1 folder will not have been cleared.

Expected behavior

To be consistent with our cache clearing, the AMP homepage should be cleared.

Additional context

We could use the after_rocket_clean_home hook in our AMP compatibility file to clear the homepage's cache.

Related ticket: https://secure.helpscout.net/conversation/1474551288/253298?folderId=2135277

Backlog Grooming (for WP Media dev team use only)

• Reproduce the problem
• Identify the root cause
• Scope a solution
• Estimate the effort

[piotrbak]

@vmanthos It's a duplicate:
#3444

[vmanthos]

Apologies @piotrbak. I searched for AMP specifically and missed that one.

I'll close this since a solution to #3444 will also apply here.