--- /dev/null
+<?php
+
+namespace Drupal\contact\Plugin\rest\resource;
+
+use Drupal\rest\Plugin\rest\resource\EntityResource;
+
+/**
+ * Customizes the entity REST Resource plugin for Contact's Message entities.
+ *
+ * Message entities are not stored, so they cannot be:
+ * - retrieved (GET)
+ * - modified (PATCH)
+ * - deleted (DELETE)
+ * Messages can only be sent/created (POST).
+ */
+class ContactMessageResource extends EntityResource {
+
+ /**
+ * {@inheritdoc}
+ */
+ public function availableMethods() {
+ return ['POST'];
+ }
+
+}