Start optional object cache for parsed and preprocessed template posts

admin/settings/index.php

@@ -48,6 +48,14 @@
     'default_value' => false,
   ],
 
+  [
+    'name' => 'object_cache_processed_template_post',
+    'field_type' => 'checkbox',
+    'label' => 'Object cache for parsed and pre-processed template posts (Experimental)',
+    'default_value' => false,
+    'beta' => true,
+  ],
+
   [
     'name' => 'sass_in_browser',
     'field_type' => 'checkbox',
@@ -106,13 +114,23 @@ function get_settings( $field_name = null, $default_value = null ) {
   return $settings;
 }
 
-function set_settings( $settings ) {
+// Alias
+function get_setting( $field_name = null, $default_value = null ) {
+  return get_settings($field_name, $default_value);
+}
 
+function set_settings( $settings ) {
   update_option( template_system::$state->settings_key, $settings );
-
   return $settings;
 }
 
+function set_setting( $key, $value ) {
+  $settings = template_system\get_settings();
+  if (!is_array($settings)) $settings = [];
+  $settings[ $key ] = $value;
+  return template_system\set_settings( $settings );
+}
+
 function settings_page() {
   require_once __DIR__.'/page.php';
 };

admin/settings/page.php

@@ -1,5 +1,6 @@
 <?php
 namespace tangible\template_system;
+
 use tangible\api;
 use tangible\template_system;
 

admin/template-post/cache.php

@@ -0,0 +1,73 @@
+<?php
+/**
+ * Object cache for pre-processed template posts
+ * 
+ * > Use the Transients API if you need to guarantee that your data will be cached. If persistent caching is configured, then the transients functions will use the wp_cache_* functions described in this document. However if persistent caching has not been enabled, then the data will instead be cached to the options table.
+ * 
+ * @see https://developer.wordpress.org/apis/transients
+ * @see https://developer.wordpress.org/reference/classes/wp_object_cache/
+ * @see https://developer.wordpress.org/advanced-administration/performance/cache/
+ */
+namespace tangible\template_system;
+
+use tangible\html;
+use tangible\template_system;
+
+function is_processed_template_post_cache_enabled() {
+  // See /admin/settings
+  return template_system\get_setting('object_cache_processed_template_post');
+}
+
+function get_template_post_cache_key($post) {
+  $type = $post->post_type;
+  $id = $post->ID;
+  return 'tangible_template_post_' . $type . '_' . $id;
+}
+
+function get_processed_template_post_with_cache( $post ) {
+
+  $cache_key = template_system\get_template_post_cache_key($post);
+
+  // \tangible\see( $post);
+
+  if (($processed = get_transient($cache_key))!==false) {
+    return $processed;
+  }
+
+  return template_system\process_and_cache_template_post($post, $cache_key);
+}
+
+/**
+ * Process and cache post content
+ */
+function process_and_cache_template_post( $post, $cache_key = null ) {
+
+  if (empty($cache_key)) {
+    $cache_key = template_system\get_template_post_cache_key($post);  
+  }
+
+  $metadata = [
+    'time' => gmdate('Y-m-d H:i:s'),
+    'type' => $post->post_type,
+    'id' => $post->ID
+  ];
+  $prefix = '<!-- Parsed and cached: ' . json_encode($metadata) . " -->\n";
+  $content = html\parse( $prefix . ($post->post_content) );
+  $processed = [
+    'parsed_content' => $content,
+    // ..Possibly other pre-processed template data
+  ] + $metadata;
+
+  set_transient($cache_key, $processed);
+
+  return $processed;
+}
+
+/**
+ * Flush cache
+ */
+function delete_processed_template_post_cache( $post ) {
+  return delete_transient(
+    template_system\get_template_post_cache_key($post)
+  );
+}

admin/template-post/index.php

@@ -1,5 +1,6 @@
 <?php
 
+require_once __DIR__ . '/cache.php';
 require_once __DIR__ . '/data.php';
 require_once __DIR__ . '/fields.php';
 require_once __DIR__ . '/save.php';

admin/template-post/render.php

@@ -6,6 +6,7 @@
  * @see /admin/template-post/script
  * @see /admin/template-assets/variable
  */
+use tangible\html;
 use tangible\template_system;
 
 $plugin->render_template_post = function(
@@ -16,6 +17,9 @@
 
   $is_post = true;
 
+  // Capture any style, script, or unexpected output
+  ob_start();
+
   // Direct post data
   if (is_array($post) && isset($post['content'])) {
 
@@ -24,12 +28,28 @@
 
   } else {
     if (is_numeric( $post )) $post = get_post( $post );
-    if ( ! is_a( $post, 'WP_Post' )) return;
+    if ( ! is_a( $post, 'WP_Post' )) {
+      ob_end_clean();
+      return;
+    }
+
     $content = $post->post_content;
-  }
 
-  // Capture any style, script, or unexpected output
-  ob_start();
+    /**
+     * Post content - Optionally processed and cached
+     * Passed to `$html->render_with_catch_exit()` which accepts string
+     * or parsed nodes.
+     * @see ./cache
+     */
+    if (template_system\is_processed_template_post_cache_enabled()) {
+
+      // Delete cache for testing
+      // template_system\delete_processed_template_post_cache($post);
+
+      $processed = template_system\get_processed_template_post_with_cache( $post );
+      $content = $processed['parsed_content'] ?? $content;
+    }
+  }
 
   /**
    * Local variable scope

admin/template-post/save.php

@@ -1,4 +1,5 @@
 <?php
+use tangible\template_system;
 
 $plugin->is_saving_template_post = false;
 
@@ -97,6 +98,13 @@
     if ( isset( $fields['style'] ) ) {
       $plugin->maybe_save_style_compiled( $post, $fields['style'] );
     }
+
+    /**
+     * Optionally pre-process template post on save
+     */
+    if (template_system\is_processed_template_post_cache_enabled()) {
+      template_system\process_and_cache_template_post( $post );
+    }
   }
 
   return $result;
@@ -146,6 +154,13 @@
     }
   }
 
+  /**
+   * Optionally pre-process template post on save
+   */
+  if (template_system\is_processed_template_post_cache_enabled()) {
+    template_system\process_and_cache_template_post( $post );
+  }
+
 }, 10, 3 );
 
 /**