Refactored polls module into layered architecture with typed domain objects, isolated SSE handling, and comprehensive tests.

owlbot/builtin_modules/polls/static/shared/poll-events.js

@@ -0,0 +1,75 @@
+// Copyright 2026 Logan Fick
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+function isRecord(value) {
+    return typeof value === "object" && value !== null && !Array.isArray(value);
+}
+
+function parseEventData(event) {
+    try {
+        return JSON.parse(event.data);
+    } catch {
+        return null;
+    }
+}
+
+export function isKeepalivePayload(value) {
+    return isRecord(value) && Number.isFinite(value.time_remaining);
+}
+
+export function isPollEndedPayload(value) {
+    return (
+        isRecord(value) &&
+        typeof value.results_url === "string" &&
+        value.results_url.length > 0
+    );
+}
+
+export function isTallyPayload(value, optionCount) {
+    return (
+        isRecord(value) &&
+        Array.isArray(value.counts) &&
+        value.counts.length === optionCount &&
+        value.counts.every((count) => Number.isInteger(count) && count >= 0)
+    );
+}
+
+export class PollEventStream {
+    constructor(url, { onClosed } = {}) {
+        this.source = new EventSource(url);
+        this.onClosed = onClosed;
+
+        this.source.addEventListener("error", () => {
+            if (this.source.readyState === EventSource.CLOSED) {
+                this.close();
+                if (this.onClosed) {
+                    this.onClosed();
+                }
+            }
+        });
+    }
+
+    on(eventName, handler, validator = () => true) {
+        this.source.addEventListener(eventName, (event) => {
+            const data = parseEventData(event);
+            if (validator(data)) {
+                handler(data);
+            }
+        });
+    }
+
+    close() {
+        this.source.close();
+    }
+}