Adding codeblocks.js.

assets/js/codeblocks.js

@@ -0,0 +1,29 @@
+/**
+ * @file
+ * A JavaScript file to add a copy code button to codeblocks.
+ */
+
+(function () {
+  async function writeClipboardText(text) {
+    try {
+      await navigator.clipboard.writeText(text);
+    } catch (error) {
+      console.error(error.message);
+    }
+  }
+
+  const copybuttons = document.querySelectorAll('[data-codebutton]');
+  copybuttons.forEach(function (button) {
+    button.addEventListener('click', function (e) {
+      const codeblock = e.target.parentElement;
+      const codeid = e.target.dataset.codebutton;
+      const codesnippet = codeblock.querySelector('[data-codetext]').getAttribute('content');
+      const codearea = codeblock.querySelector('pre');
+      codearea.classList.add('flash-item');
+      writeClipboardText(JSON.parse(codesnippet));
+      setTimeout(function () {
+        codearea.classList.remove('flash-item');
+      }, 700);
+    });
+  });
+})();