fix: Fixes incorrect order of array_replace_recursive arguments & other issues

* Fixes pantheon-systems#433
* Fixes $432
* Fixes pantheon-systems#431
* Further clean-up & standardization between object-cache.php & wp-redis.php.
* Fixes incorrect order of array_replace_recursive arguments.
* Addresses issue with port still not being null for socket connections due to defaults array_repalce_recursive use.

Author: timnolte

object-cache.php

@@ -1247,10 +1247,11 @@ public function build_client_parameters( $redis_server ) {
 			// Attempt to automatically load Pantheon's Redis config from the env.
 			if ( isset( $_SERVER['CACHE_HOST'] ) ) {
 				$redis_server = [
-					'host' => wp_strip_all_tags( $_SERVER['CACHE_HOST'] ),
-					'port' => isset( $_SERVER['CACHE_PORT'] ) ? wp_strip_all_tags( $_SERVER['CACHE_PORT'] ) : $port,
-					'auth' => isset( $_SERVER['CACHE_PASSWORD'] ) ? wp_strip_all_tags( $_SERVER['CACHE_PASSWORD'] ) : null,
-					'database' => isset( $_SERVER['CACHE_DB'] ) ? wp_strip_all_tags( $_SERVER['CACHE_DB'] ) : $database,
+					'host' => strip_tags( $_SERVER['CACHE_HOST'] ),
+					'port' => ! empty( $_SERVER['CACHE_PORT'] ) ? strip_tags( $_SERVER['CACHE_PORT'] ) : $port,
+					// Don't attempt to sanitize passwords as this can break authentication.
+					'auth' => ! empty( $_SERVER['CACHE_PASSWORD'] ) ? $_SERVER['CACHE_PASSWORD'] : null,
+					'database' => ! empty( $_SERVER['CACHE_DB'] ) ? strip_tags( $_SERVER['CACHE_DB'] ) : $database,
 				];
 			} else {
 				$redis_server = [
@@ -1263,6 +1264,7 @@ public function build_client_parameters( $redis_server ) {
 
 		if ( file_exists( $redis_server['host'] ) && 'socket' === filetype( $redis_server['host'] ) ) { // unix socket connection.
 			// port must be null or socket won't connect.
+			unset( $redis_server['port'] );
 			$port = null;
 		}
 
@@ -1275,7 +1277,7 @@ public function build_client_parameters( $redis_server ) {
 		// 1s timeout, 100ms delay between reconnections.
 
 		// merging the defaults with the original $redis_server enables any custom parameters to get sent downstream to the redis client.
-		return array_replace_recursive( $redis_server, $defaults );
+		return array_replace_recursive( $defaults, $redis_server );
 	}
 
 	/**

wp-redis.php

@@ -35,21 +35,26 @@
  */
 function wp_redis_get_info() {
 	global $wp_object_cache, $redis_server;
+	// Default Redis port.
+	$port = 6379;
+	// Default Redis database number.
+	$database = 0;
 
 	if ( empty( $redis_server ) ) {
 		// Attempt to automatically load Pantheon's Redis config from the env.
 		if ( isset( $_SERVER['CACHE_HOST'] ) ) {
 			$redis_server = [
-				'host' => sanitize_text_field( $_SERVER['CACHE_HOST'] ),
-				'port' => isset( $_SERVER['CACHE_PORT'] ) ? sanitize_text_field( $_SERVER['CACHE_PORT'] ) : 6379,
-				'auth' => isset( $_SERVER['CACHE_PASSWORD'] ) ? sanitize_text_field( $_SERVER['CACHE_PASSWORD'] ) : null,
-				'database' => isset( $_SERVER['CACHE_DB'] ) ? sanitize_text_field( $_SERVER['CACHE_DB'] ) : 0,
+				'host' => strip_tags( $_SERVER['CACHE_HOST'] ),
+				'port' => ! empty( $_SERVER['CACHE_PORT'] ) ? strip_tags( $_SERVER['CACHE_PORT'] ) : $port,
+				// Don't attempt to sanitize passwords as this can break authentication.
+				'auth' => ! empty( $_SERVER['CACHE_PASSWORD'] ) ? $_SERVER['CACHE_PASSWORD'] : null,
+				'database' => ! empty( $_SERVER['CACHE_DB'] ) ? strip_tags( $_SERVER['CACHE_DB'] ) : $database,
 			];
 		} else {
 			$redis_server = [
 				'host' => '127.0.0.1',
-				'port' => 6379,
-				'database' => 0,
+				'port' => $port,
+				'database' => $database,
 			];
 		}
 	}
@@ -73,7 +78,7 @@ function wp_redis_get_info() {
 	} else {
 		$uptime_in_days .= ' days';
 	}
-	$database  = ! empty( $redis_server['database'] ) ? $redis_server['database'] : 0;
+	$database  = ! empty( $redis_server['database'] ) ? $redis_server['database'] : $database;
 	$key_count = 0;
 	if ( isset( $info[ 'db' . $database ] ) && preg_match( '#keys=([\d]+)#', $info[ 'db' . $database ], $matches ) ) {
 		$key_count = $matches[1];