git commit -m 'Issue #3437655 by allan.ordogh: Add langcode paramater'

src/StackMiddleware/PathAndFormatSetter.php

@@ -147,7 +147,7 @@ class PathAndFormatSetter implements HttpKernelInterface {
     // Lookup bundle & uuid for node id in our custom key-value store.
     if ($info = $this->store->get($path)) {
       // Build the default JSON-API path.
-      $path = $this->buildJsonApiPath($info);
+      $path = $this->buildJsonApiPath($info, $langcode);
 
       // Replace immutable request with modified clone.
       if(!empty($langcode)) {
@@ -242,11 +242,11 @@ class PathAndFormatSetter implements HttpKernelInterface {
    * @return string
    *   The
    */
-  protected function buildJsonApiPath($info) {
+  protected function buildJsonApiPath($info, $langcode) {
     if (isset($info['bundle']) && $info['bundle'] !== null) {
-      return '/' . $this->jsonapiPrefix . '/' . $info['type'] . '/' . $info['bundle'] . '/' . $info['uuid'];
+      return '/' . $langcode . '/' . $this->jsonapiPrefix . '/' . $info['type'] . '/' . $info['bundle'] . '/' . $info['uuid'];
     } else {
-      return '/' . $this->jsonapiPrefix . '/' . $info['type'] . '/' . $info['uuid'];
+      return '/' . $langcode . '/' . $this->jsonapiPrefix . '/' . $info['type'] . '/' . $info['uuid'];
     }
   }