Issue #3203542: Support ServerSideRender component

js/api-fetch.es6.js

@@ -551,6 +551,28 @@
         });
       },
     },
+    'render-block': {
+      method: 'GET',
+      regex: /\/wp\/v2\/block-renderer\/([\w\-\/]+)(\?.*)?/g,
+      process(matches, data) {
+        return new Promise((resolve, reject) => {
+          $.ajax({
+            method: 'POST',
+            url: Drupal.url(`gutenberg/render-block${matches[2]}`),
+            data: {
+              ...data,
+              blockName: matches[1],
+            },
+            dataType: 'json',
+          })
+            .done(resolve)
+            .fail(error => {
+              errorHandler(error, reject);
+            });
+        });
+      },
+    },
+
     'block-options': {
       method: 'OPTIONS',
       regex: /\/wp\/v2\/blocks/g,