1 files changed, 26 insertions, 0 deletions
diff --git a/testing/web-platform/tests/tools/third_party/websockets/example/quickstart/counter.js b/testing/web-platform/tests/tools/third_party/websockets/example/quickstart/counter.js
new file mode 100644
index 0000000000..37d892a28b
--- /dev/null
+++ b/testing/web-platform/tests/tools/third_party/websockets/example/quickstart/counter.js
@@ -0,0 +1,26 @@
+window.addEventListener("DOMContentLoaded", () => {
+  const websocket = new WebSocket("ws://localhost:6789/");
+
+  document.querySelector(".minus").addEventListener("click", () => {
+    websocket.send(JSON.stringify({ action: "minus" }));
+  });
+
+  document.querySelector(".plus").addEventListener("click", () => {
+    websocket.send(JSON.stringify({ action: "plus" }));
+  });
+
+  websocket.onmessage = ({ data }) => {
+    const event = JSON.parse(data);
+    switch (event.type) {
+      case "value":
+        document.querySelector(".value").textContent = event.value;
+        break;
+      case "users":
+        const users = `${event.count} user${event.count == 1 ? "" : "s"}`;
+        document.querySelector(".users").textContent = users;
+        break;
+      default:
+        console.error("unsupported event", event);
+    }
+  };
+});