Support multiple namespaces.

Author: Jason Smith

lib/example.json

@@ -0,0 +1,16 @@
+{
+  "$schema": "http://json-schema.org/draft-04/schema#",
+  "category": "atom",
+  "title": "Example",
+  "type": "object",
+  "format": "grid",
+  "properties": {
+    "text": {
+      "title": "Text",
+      "type": "string",
+      "options": {
+        "grid_columns": 4
+      }
+    }
+  }
+}

lib/example.twig

@@ -0,0 +1,2 @@
+Test sample twig template.
+{{- string|striptags('')|raw -}}

patternkit.info

@@ -11,5 +11,6 @@ files[] = src/PatternkitDrupalCachedLib.php
 files[] = src/PatternkitDrupalTwigLib.php
 files[] = src/PatternkitEditorConfig.php
 files[] = src/PatternkitLibInterface.php
+files[] = src/PatternkitTwigWrapper.php
 files[] = src/PatternkitPattern.php
 files[] = src/PatternkitRESTLib.php

patternkit.module

@@ -86,6 +86,22 @@ function patternkit_pattern_libraries() {
     }
   }
 
+  // Triggers initialization of the Twig wrapper.
+  PatternkitTwigWrapper::getInstance($libraries);
+
+  return $libraries;
+}
+
+/**
+ * Implements hook_patternkit_library().
+ */
+function patternkit_patternkit_library() {
+  $libraries = array();
+
+  $module_path = drupal_get_path('module', 'patternkit');
+  $lib_path = $module_path . DIRECTORY_SEPARATOR . 'lib';
+  $libraries[] = new PatternkitDrupalTwigLib('Example', $lib_path);
+
   return $libraries;
 }
 

src/PatternkitDrupalTwigLib.php

@@ -11,6 +11,8 @@ class PatternkitDrupalTwigLib extends PatternkitDrupalCachedLib {
 
   private $title;
 
+  private $metadata;
+
   /**
    * PatternkitDrupalTwigLib constructor.
    *
@@ -46,6 +48,8 @@ public function fetchPatternAssets(PatternkitPattern $pattern,
   /**
    * Returns the id of the Pattern Library.
    *
+   * The id also functions as the namespace for the twig templates.
+   *
    * @return string
    *   The Pattern Library id.
    */
@@ -210,14 +214,12 @@ public function getEditor($subtype = NULL,
    *   Array of metadata objects found.
    */
   protected function getRawMetadata() {
-    static $metadata;
-
     // Use static pattern to avoid rebuilding multiple times per request.
-    if (is_null($metadata)) {
+    if (is_null($this->metadata)) {
 
       $it = new RecursiveDirectoryIterator($this->path);
       $filter = ['json', 'twig'];
-      $metadata = [];
+      $this->metadata = [];
       $components = [];
 
       /** @var \SplFileInfo $file */
@@ -254,8 +256,9 @@ protected function getRawMetadata() {
 
           $subtype = "pk_$module_name";
           $pattern->subtype = $subtype;
-          // URL is redundant for the twig based components.
-          $pattern->url = $module_name;
+          // URL is redundant for the twig based components, so we use it to
+          // store namespace.
+          $pattern->url = $this->getId();
         }
         else {
           // Create the pattern from defaults.
@@ -273,31 +276,30 @@ protected function getRawMetadata() {
         }
 
         if (!empty($data['twig'])) {
-          $twig_file = $data['twig']
-                       . DIRECTORY_SEPARATOR . $module_name . '.twig';
+          $twig_file = $data['twig'];
           if (file_exists($twig_file)) {
             $pattern->filename = $twig_file;
             $pattern->template = file_get_contents($twig_file);
           }
         }
 
-        $metadata[$module_name] = $pattern;
+        $this->metadata[$module_name] = $pattern;
       }
 
-      foreach ($metadata as $pattern_type => $pattern) {
+      foreach ($this->metadata as $pattern_type => $pattern) {
         // Replace any $ref links with relative paths.
         if (!isset($pattern->schema->properties)) {
           continue;
         }
         $pattern->schema->properties = _patternkit_schema_ref(
           $pattern->schema->properties,
-          $metadata
+          $this->metadata
         );
-        $metadata[$pattern_type] = $pattern;
+        $this->metadata[$pattern_type] = $pattern;
       }
     }
 
-    return $metadata;
+    return $this->metadata;
   }
 
   /**
@@ -321,55 +323,11 @@ public function getRenderedPatternMarkup(
     $template = $pattern->filename;
     $variables = $config->fields;
 
-    return $this->renderTwigTemplate($template, $variables);
-  }
-
-  /**
-   * Returns a singleton version of the twig template engine.
-   *
-   * @return Twig_Environment
-   *   Twig environment object.
-   *
-   * @throws \Twig_Error_Loader
-   *   Twig engine instance object.
-   */
-  public function getTwigInstance() {
-    static $twig_engine;
-
-    if (!is_object($twig_engine)) {
-      // Setup twig environment.
-      // @TODO: Properly libraryize this.
-      require_once DRUPAL_ROOT . '/sites/all/libraries/Twig/Autoloader.php';
-      Twig_Autoloader::register();
-
-      $loader = new Twig_Loader_Filesystem();
-
-      $metadata = $this->getRawMetadata();
-      foreach ($metadata as $module_name => $module) {
-        if (!empty($module->filename)) {
-          $templatesDirectory = DRUPAL_ROOT . DIRECTORY_SEPARATOR . dirname(
-              $module->filename
-            );
-
-          // Namespacing is not necessary here, as each "engine" is unique to
-          // the "library".
-          $loader->addPath($templatesDirectory);
-        }
-      }
-
-      $twig_engine = new Twig_Environment(
-        $loader,
-        array(
-          'autorender'  => (bool) variable_get('pktwig_auto_render', TRUE),
-          'autoescape'  => (bool) variable_get('pktwig_auto_escape', FALSE),
-          'auto_reload' => (bool) variable_get('pktwig_auto_reload', FALSE),
-          'cache'       => variable_get('pktwig_template_cache_path', '/tmp/twig_compilation_cache'),
-          'debug'       => (bool) variable_get('pktwig_debug', FALSE),
-        )
-      );
+    // Add the namespace, if provided.
+    if (!empty($pattern->url)) {
+      $template = '@' . $pattern->url . '#/' . $template;
     }
-
-    return $twig_engine;
+    return $this->renderTwigTemplate($template, $variables);
   }
 
   /**
@@ -385,18 +343,27 @@ public function getTwigInstance() {
    */
   public function renderTwigTemplate($template, array $variables = array()) {
 
-    $content = '';
-    if (file_exists($template)) {
+    $namespace = '';
+    $file = $template;
+
+    // If a namespace is provided, break it up.
+    if ($template[0] == '@') {
+      list($namespace, $file) = explode('#', $template);
+    }
+
+    try {
+      $bare = basename($file);
+
       try {
-        $twig     = $this->getTwigInstance();
-        $template = $twig->loadTemplate(basename($template));
+        $twig     = PatternkitTwigWrapper::getInstance()->getTwigInstance();
+        $template = $twig->loadTemplate("$namespace/$bare");
         $content  = $template->render($variables);
       }
       catch (Exception $e) {
         $content = t(
           'Twig error (!exc} "!error"',
           array(
-            '!exc'   => 'tst',
+            '!exc'   => get_class($e),
             '!error' => $e->getMessage(),
           )
         );
@@ -410,7 +377,7 @@ public function renderTwigTemplate($template, array $variables = array()) {
         );
       }
     }
-    else {
+    catch (Exception $e) {
       $content = t(
         'Template (!template) not found',
         array(

src/PatternkitPattern.php

@@ -52,9 +52,9 @@ public function __construct(PatternkitLibInterface $library, $schema = array())
   /**
    * The subtype for the pattern. Typically "pk_$pattern".
    *
-   * @var string
+   * Must be unique across the site. Is used by Panels to address config, etc.
    *
-   * This is mostly in use with Drupal to avoid panels namespace conflicts.
+   * @var string
    */
   public $subtype;
 

src/PatternkitTwigWrapper.php

@@ -0,0 +1,114 @@
+<?php
+/**
+ * @file
+ * customer-portal-kbase-copy
+ *
+ * - Created by jassmith on 2/2/18
+ */
+
+class PatternkitTwigWrapper {
+
+  protected $metadata;
+  protected $libraries;
+  protected $twigEngine;
+
+  /**
+   * PatternkitTwigWrapper constructor.
+   *
+   * @param array $libraries
+   *   The collection of patterns and metadata.
+   *
+   * @return PatternkitTwigWrapper
+   *   Returns the singleton PatternkitTwigWrapper.
+   */
+  public static function getInstance(array $libraries = NULL) {
+    static $instance;
+
+    if (empty($instance)) {
+      $instance = new static($libraries);
+    }
+
+    return $instance;
+  }
+
+  /**
+   * PatternkitTwigWrapper constructor.
+   *
+   * @param array $libraries
+   *   The collection of patterns and metadata.
+   */
+  protected function __construct(array $libraries) {
+    if (empty($libraries)) {
+      watchdog('patternkit', 'Metadata not passed to constructor for patternTwig', WATCHDOG_ERROR);
+    }
+
+    $this->libraries = $libraries;
+
+    // Collect all metadata.
+    $this->metadata = [];
+
+    foreach ($libraries as $library) {
+      $meta = $library->getCachedMetadata();
+      $this->metadata = array_merge($this->metadata, $meta);
+    }
+
+    // Setup twig environment.
+    // @TODO: Properly libraryize this.
+    require_once DRUPAL_ROOT . '/sites/all/libraries/Twig/Autoloader.php';
+    Twig_Autoloader::register();
+
+    $loader = new Twig_Loader_Filesystem();
+
+    foreach ($this->metadata as $module_name => $module) {
+      if (!empty($module->filename)) {
+        $templatesDirectory = DRUPAL_ROOT . DIRECTORY_SEPARATOR . dirname(
+            $module->filename
+          );
+
+        // We put the namespace into the url, since it's otherwise unused
+        // and serves a similar purpose.
+        try {
+          $loader->addPath($templatesDirectory, $module->url);
+
+          // To support empty namespaces (for now)
+          $loader->addPath($templatesDirectory);
+        }
+        catch (Twig_Error_Loader $e) {
+          drupal_set_message("Error loading $templatesDirectory", 'warning');
+          watchdog(
+            'patternkit',
+            'Error loading @module',
+            ['@module' => $templatesDirectory],
+            WATCHDOG_WARNING
+          );
+        }
+      }
+    }
+
+    $this->twigEngine = new Twig_Environment(
+      $loader,
+      array(
+        'autorender'  => (bool) variable_get('pktwig_auto_render', TRUE),
+        'autoescape'  => (bool) variable_get('pktwig_auto_escape', FALSE),
+        'auto_reload' => (bool) variable_get('pktwig_auto_reload', FALSE),
+        'cache'       => variable_get('pktwig_template_cache_path', '/tmp/twig_compilation_cache'),
+        'debug'       => (bool) variable_get('pktwig_debug', FALSE),
+      )
+    );
+
+  }
+
+  /**
+   * Returns a singleton version of the twig template engine.
+   *
+   * @return Twig_Environment
+   *   Twig environment object.
+   *
+   * @throws \Twig_Error_Loader
+   *   Twig engine instance object.
+   */
+  public function getTwigInstance() {
+    return $this->twigEngine;
+  }
+
+}