WIP: Phase 3B playback engine handoff

server/test/playback-api.test.js

@@ -0,0 +1,249 @@
+const test = require("node:test");
+const assert = require("node:assert/strict");
+const { createApp } = require("../src/app");
+const { loadConfig } = require("../src/config");
+const { openDatabase } = require("../src/database");
+const { runMigrations } = require("../src/database/migrate");
+
+function testConfig() {
+  return loadConfig({
+    NODE_ENV: "test",
+    HOST: "127.0.0.1",
+    PORT: "0",
+    DATABASE_PATH: ":memory:",
+    APP_TIMEZONE: "America/Chicago",
+    S3_ENDPOINT: "http://seaweedfs:8333",
+    S3_BUCKET: "announcements-test",
+  });
+}
+
+function createPlaybackStub({ domainError = null } = {}) {
+  const calls = [];
+  let revision = 10;
+  const snapshot = (action = "get") => ({
+    protocolVersion: 1,
+    outputId: "global",
+    playbackRevision: revision,
+    action,
+  });
+  const action = (name) => () => {
+    calls.push([name]);
+    revision += 1;
+    return snapshot(name);
+  };
+  return {
+    calls,
+    domainChanged(change) {
+      calls.push(["domainChanged", change]);
+      if (domainError) throw domainError;
+      return snapshot("domainChanged");
+    },
+    getSnapshot() {
+      calls.push(["getSnapshot"]);
+      return snapshot();
+    },
+    pause: action("pause"),
+    reconcile(reason) {
+      calls.push(["reconcile", reason]);
+      return snapshot("reconcile");
+    },
+    resume: action("resume"),
+    next: action("next"),
+    previous: action("previous"),
+    reload: action("reload"),
+    enterStatic(assetId) {
+      calls.push(["enterStatic", assetId]);
+      revision += 1;
+      return snapshot("static");
+    },
+    setMode(mode) {
+      calls.push(["setMode", mode]);
+      revision += 1;
+      return snapshot("mode");
+    },
+    activatePlaylist(playlistId) {
+      calls.push(["activatePlaylist", playlistId]);
+      revision += 1;
+      const current = snapshot("activate");
+      return {
+        activation: "active",
+        playlistId,
+        playback: { revision: current.playbackRevision },
+        snapshot: current,
+      };
+    },
+  };
+}
+
+async function createHarness(t, { domainError = null } = {}) {
+  const database = openDatabase({ path: ":memory:" });
+  const migrations = runMigrations(database);
+  const playbackService = createPlaybackStub({ domainError });
+  const invalidations = [];
+  const app = createApp({
+    config: testConfig(),
+    database,
+    imageProcessor: {},
+    lifecycle: { ready: true, stopping: false },
+    logger: { info() {}, warn() {}, error() {} },
+    migrations,
+    onPlaylistsChanged: (event) => invalidations.push(event),
+    playbackService,
+    storage: {
+      health() {
+        return { status: "healthy", checkedAt: null, lastSuccessAt: null };
+      },
+    },
+  });
+  const server = app.listen(0, "127.0.0.1");
+  await new Promise((resolve, reject) => {
+    server.once("listening", resolve);
+    server.once("error", reject);
+  });
+  t.after(async () => {
+    await new Promise((resolve) => server.close(resolve));
+    database.close();
+  });
+  return {
+    baseUrl: `http://127.0.0.1:${server.address().port}`,
+    database,
+    invalidations,
+    playbackService,
+  };
+}
+
+async function requestJson(baseUrl, path, { body, ...init } = {}) {
+  const response = await fetch(`${baseUrl}${path}`, {
+    ...init,
+    ...(body === undefined
+      ? {}
+      : {
+          headers: { "content-type": "application/json", ...init.headers },
+          body: JSON.stringify(body),
+        }),
+  });
+  return { response, body: await response.json() };
+}
+
+test("playback REST routes delegate every command to the one playback service", async (t) => {
+  const harness = await createHarness(t);
+
+  const read = await requestJson(harness.baseUrl, "/api/playback");
+  assert.equal(read.response.status, 200);
+  assert.equal(read.body.playbackRevision, 10);
+
+  const commands = [
+    ["POST", "/api/playback/pause", undefined, "pause"],
+    ["POST", "/api/playback/resume", undefined, "resume"],
+    ["POST", "/api/playback/next", undefined, "next"],
+    ["POST", "/api/playback/previous", undefined, "previous"],
+    ["POST", "/api/playback/reload", undefined, "reload"],
+    ["POST", "/api/playback/static", { assetId: "asset-static" }, "static"],
+    ["PUT", "/api/playback/mode", { mode: "off" }, "mode"],
+  ];
+  for (const [method, path, body, action] of commands) {
+    const result = await requestJson(harness.baseUrl, path, { method, body });
+    assert.equal(result.response.status, 200);
+    assert.equal(result.body.action, action);
+  }
+
+  assert.deepEqual(harness.playbackService.calls, [
+    ["getSnapshot"],
+    ["pause"],
+    ["resume"],
+    ["next"],
+    ["previous"],
+    ["reload"],
+    ["enterStatic", "asset-static"],
+    ["setMode", "off"],
+  ]);
+});
+
+test("playlist activation delegates directly to the playback authority", async (t) => {
+  const harness = await createHarness(t);
+  const result = await requestJson(
+    harness.baseUrl,
+    "/api/playlists/playlist-a/activate",
+    { method: "POST" },
+  );
+
+  assert.equal(result.response.status, 200);
+  assert.equal(result.body.activation, "active");
+  assert.equal(result.body.playlistId, "playlist-a");
+  assert.deepEqual(harness.playbackService.calls, [
+    ["activatePlaylist", "playlist-a"],
+  ]);
+  assert.deepEqual(harness.invalidations, []);
+});
+
+test("semantic domain edits reconcile playback independently of list invalidation", async (t) => {
+  const harness = await createHarness(t);
+  const timestamp = Date.now();
+  harness.database
+    .prepare(
+      `INSERT INTO assets (
+        id, source_sha256, display_name, original_filename, status,
+        created_at, updated_at
+      ) VALUES (?, ?, ?, ?, 'ready', ?, ?)`,
+    )
+    .run(
+      "unreferenced-asset",
+      "a".repeat(64),
+      "Unreferenced",
+      "unreferenced.png",
+      timestamp,
+      timestamp,
+    );
+
+  const settings = await requestJson(harness.baseUrl, "/api/settings", {
+    method: "PATCH",
+    body: { defaultBlurPx: 21 },
+  });
+  assert.equal(settings.response.status, 200);
+  const asset = await requestJson(
+    harness.baseUrl,
+    "/api/assets/unreferenced-asset",
+    { method: "PATCH", body: { displayName: "Renamed unreferenced" } },
+  );
+  assert.equal(asset.response.status, 200);
+
+  assert.deepEqual(harness.playbackService.calls, [
+    ["reconcile", "before_domain_change"],
+    [
+      "domainChanged",
+      { reason: "settings_updated", playlistIds: null, settingsRevision: 2 },
+    ],
+    ["reconcile", "before_domain_change"],
+    [
+      "domainChanged",
+      {
+        reason: "asset_updated",
+        playlistIds: [],
+        assetId: "unreferenced-asset",
+      },
+    ],
+  ]);
+  assert.deepEqual(harness.invalidations, [
+    { reason: "settings_updated", playlistIds: null, settingsRevision: 2 },
+  ]);
+});
+
+test("a playback reconciliation failure is surfaced after the domain commit", async (t) => {
+  const harness = await createHarness(t, {
+    domainError: new Error("reconciliation failed"),
+  });
+  const result = await requestJson(harness.baseUrl, "/api/playlists", {
+    method: "POST",
+    body: { name: "Committed before reconciliation" },
+  });
+
+  assert.equal(result.response.status, 500);
+  assert.equal(result.body.error.code, "INTERNAL_ERROR");
+  assert.equal(
+    harness.database.prepare("SELECT COUNT(*) AS count FROM playlists").get()
+      .count,
+    1,
+  );
+  assert.equal(harness.invalidations.length, 0);
+  assert.equal(harness.playbackService.calls[0][0], "domainChanged");
+});

server/test/playlists-service.test.js

@@ -4,6 +4,7 @@ const crypto = require("node:crypto");
 const { openDatabase } = require("../src/database");
 const { runMigrations } = require("../src/database/migrate");
 const { createAssetService } = require("../src/assets/service");
+const { createPlaybackService } = require("../src/playback");
 const {
   MAX_DURATION_MS,
   MIN_DURATION_MS,
@@ -19,13 +20,22 @@ function createHarness() {
   let idCounter = 0;
   let assetCounter = 0;
   const changes = [];
+  let playbackService;
   const service = createPlaylistService({
     database,
     now: () => clock,
     createId: () =>
       `00000000-0000-4000-8000-${String(++idCounter).padStart(12, "0")}`,
-    onChanged: (change) => changes.push(change),
+    onBeforeChange: () => {
+      playbackService?.reconcile("before_domain_change");
+    },
+    onChanged: (change) => {
+      changes.push(change);
+      playbackService?.domainChanged(change);
+    },
   });
+  playbackService = createPlaybackService({ database, now: () => clock });
+  playbackService.initialize();
 
   function setNow(value) {
     clock = value;
@@ -71,7 +81,15 @@ function createHarness() {
       .get();
   }
 
-  return { changes, database, playback, seedAsset, service, setNow };
+  return {
+    changes,
+    database,
+    playback,
+    playbackService,
+    seedAsset,
+    service,
+    setNow,
+  };
 }
 
 function expectError(action, code, statusCode) {
@@ -479,7 +497,7 @@ test("activation queues at a live boundary, is idempotent, and mode off is only
     durationOverrideMs: 4000,
   });
 
-  const initial = harness.service.activate(oldPlaylist.id);
+  const initial = harness.playbackService.activatePlaylist(oldPlaylist.id);
   assert.equal(initial.activation, "active");
   assert.equal(initial.playback.currentEntryId, oldEntry.id);
   assert.equal(initial.playback.slideStartedAt, BASE_TIME);
@@ -489,7 +507,7 @@ test("activation queues at a live boundary, is idempotent, and mode off is only
     .prepare("UPDATE playback_state SET mode = 'off' WHERE output_id = 'global'")
     .run();
   harness.setNow(BASE_TIME + 1000);
-  const pending = harness.service.activate(newPlaylist.id);
+  const pending = harness.playbackService.activatePlaylist(newPlaylist.id);
   assert.equal(pending.activation, "pending");
   assert.equal(pending.playback.mode, "off");
   assert.equal(pending.playback.activePlaylistId, oldPlaylist.id);
@@ -498,18 +516,18 @@ test("activation queues at a live boundary, is idempotent, and mode off is only
   const pendingRevision = pending.playback.revision;
   const requestedAt = pending.playback.pendingPlaylistRequestedAt;
 
-  const repeated = harness.service.activate(newPlaylist.id);
+  const repeated = harness.playbackService.activatePlaylist(newPlaylist.id);
   assert.equal(repeated.activation, "pending");
   assert.equal(repeated.playback.revision, pendingRevision);
   assert.equal(repeated.playback.pendingPlaylistRequestedAt, requestedAt);
 
-  const cancel = harness.service.activate(oldPlaylist.id);
+  const cancel = harness.playbackService.activatePlaylist(oldPlaylist.id);
   assert.equal(cancel.activation, "already_active");
   assert.equal(cancel.playback.pendingPlaylistId, null);
   assert.equal(cancel.playback.currentEntryId, oldEntry.id);
 
   harness.setNow(BASE_TIME + 7000);
-  const immediate = harness.service.activate(newPlaylist.id);
+  const immediate = harness.playbackService.activatePlaylist(newPlaylist.id);
   assert.equal(immediate.activation, "active");
   assert.equal(immediate.playback.activePlaylistId, newPlaylist.id);
   assert.equal(immediate.playback.pendingPlaylistId, null);
@@ -534,7 +552,7 @@ test("paused normal playback queues and can replace a pending activation", (t) =
   harness.service.addEntry(secondTarget.id, {
     assetId: harness.seedAsset({ id: "second-target", name: "Second target" }),
   });
-  harness.service.activate(current.id);
+  harness.playbackService.activatePlaylist(current.id);
   harness.database
     .prepare(
       `UPDATE playback_state
@@ -545,14 +563,14 @@ test("paused normal playback queues and can replace a pending activation", (t) =
     .run();
 
   harness.setNow(BASE_TIME + 1000);
-  const first = harness.service.activate(firstTarget.id);
+  const first = harness.playbackService.activatePlaylist(firstTarget.id);
   assert.equal(first.activation, "pending");
   assert.equal(first.playback.activePlaylistId, current.id);
   assert.equal(first.playback.pendingPlaylistId, firstTarget.id);
   assert.equal(first.playback.pausedRemainingMs, 5000);
 
   harness.setNow(BASE_TIME + 2000);
-  const replacement = harness.service.activate(secondTarget.id);
+  const replacement = harness.playbackService.activatePlaylist(secondTarget.id);
   assert.equal(replacement.activation, "pending");
   assert.equal(replacement.playback.activePlaylistId, current.id);
   assert.equal(replacement.playback.pendingPlaylistId, secondTarget.id);
@@ -579,7 +597,7 @@ test("static and paused activation prepare the first playable normal target with
     durationOverrideMs: 9000,
   });
   assert.equal(skipped.position, 0);
-  harness.service.activate(oldPlaylist.id);
+  harness.playbackService.activatePlaylist(oldPlaylist.id);
   harness.database
     .prepare(
       `UPDATE playback_state
@@ -590,7 +608,7 @@ test("static and paused activation prepare the first playable normal target with
     )
     .run(staticAssetId);
 
-  const result = harness.service.activate(target.id);
+  const result = harness.playbackService.activatePlaylist(target.id);
   assert.equal(result.activation, "active");
   assert.equal(result.playback.activePlaylistId, target.id);
   assert.equal(result.playback.staticAssetId, staticAssetId);
@@ -611,7 +629,7 @@ test("empty activation is immediate and current-entry deletion coordinates playb
       assetId: harness.seedAsset({ id: `asset-${id}`, name: id }),
     }),
   );
-  harness.service.activate(populated.id);
+  harness.playbackService.activatePlaylist(populated.id);
   const futurePlaybackTimestamp = BASE_TIME + 100_000;
   harness.database
     .prepare(
@@ -624,10 +642,10 @@ test("empty activation is immediate and current-entry deletion coordinates playb
 
   harness.service.removeEntry(populated.id, entries[0].id);
   const afterDelete = harness.playback();
-  assert.equal(afterDelete.current_entry_id, null);
+  assert.equal(afterDelete.current_entry_id, entries[1].id);
   assert.equal(afterDelete.slide_started_at, null);
   assert.equal(afterDelete.next_slide_at, null);
-  assert.equal(afterDelete.paused_remaining_ms, null);
+  assert.equal(afterDelete.paused_remaining_ms, 7000);
   assert.equal(afterDelete.active_playlist_id, populated.id);
   assert.equal(afterDelete.mode, "off");
   assert.equal(afterDelete.static_asset_id, "asset-second");
@@ -646,7 +664,7 @@ test("empty activation is immediate and current-entry deletion coordinates playb
        WHERE output_id = 'global'`,
     )
     .run();
-  const result = harness.service.activate(empty.id);
+  const result = harness.playbackService.activatePlaylist(empty.id);
   assert.equal(result.activation, "active");
   assert.equal(result.playback.activePlaylistId, empty.id);
   assert.equal(result.playback.currentEntryId, null);
@@ -665,7 +683,7 @@ test("inactive playlist edits do not mutate authoritative playback state", (t) =
   const draftEntry = harness.service.addEntry(inactive.id, {
     assetId: harness.seedAsset({ id: "draft", name: "Draft asset" }),
   });
-  harness.service.activate(active.id);
+  harness.playbackService.activatePlaylist(active.id);
   const before = harness.playback();
 
   harness.service.update(inactive.id, { name: "Draft edited" });

server/test/runtime.test.js

@@ -1,9 +1,10 @@
 const test = require("node:test");
 const assert = require("node:assert/strict");
+const net = require("node:net");
 const { loadConfig } = require("../src/config");
 const { createRuntime } = require("../src/runtime");
 
-function testConfig() {
+function testConfig(overrides = {}) {
   return loadConfig({
     NODE_ENV: "test",
     HOST: "127.0.0.1",
@@ -20,6 +21,7 @@ function testConfig() {
     MQTT_URL: "mqtt://broker:1883",
     MQTT_PASSWORD: "mqtt-password-that-must-not-leak",
     HA_WEBHOOK_URL: "http://home-assistant:8123/api/webhook/private-id",
+    ...overrides,
   });
 }
 
@@ -171,3 +173,28 @@ test("runtime startup and shutdown are idempotent", async () => {
   assert.equal(runtime.lifecycle.ready, false);
   assert.equal(runtime.database.open, false);
 });
+
+test("a listen failure stops playback and closes startup resources", async (t) => {
+  const occupied = net.createServer();
+  occupied.listen(0, "127.0.0.1");
+  await new Promise((resolve, reject) => {
+    occupied.once("listening", resolve);
+    occupied.once("error", reject);
+  });
+  t.after(
+    () =>
+      new Promise((resolve) => {
+        occupied.close(resolve);
+      }),
+  );
+
+  const runtime = createRuntime({
+    config: testConfig({ PORT: String(occupied.address().port) }),
+    logger: silentLogger,
+    storage: testStorage(),
+  });
+
+  await assert.rejects(runtime.start(), (error) => error.code === "EADDRINUSE");
+  assert.equal(runtime.lifecycle.ready, false);
+  assert.equal(runtime.database.open, false);
+});

server/test/socket-invalidation.test.js

@@ -97,6 +97,7 @@ async function connectPollingSocket(baseUrl) {
   );
 
   return {
+    initialEvents: socketEvents(connectedPayload),
     async poll() {
       const response = await fetch(endpoint(sid), {
         signal: AbortSignal.timeout(3_000),
@@ -115,6 +116,65 @@ async function connectPollingSocket(baseUrl) {
   };
 }
 
+test("Socket.IO sends an authoritative playback snapshot on connect and after mutations", async (t) => {
+  const runtime = createRuntime({
+    config: testConfig(),
+    logger: silentLogger,
+    storage: testStorage(),
+  });
+  await runtime.start();
+  t.after(() => runtime.stop("test cleanup"));
+  const baseUrl = `http://127.0.0.1:${runtime.address.port}`;
+  const socket = await connectPollingSocket(baseUrl);
+  t.after(() => socket.close().catch(() => {}));
+
+  let initial = socket.initialEvents.find(
+    ([eventName]) => eventName === "playback:state",
+  );
+  if (!initial) {
+    initial = socketEvents(await socket.poll()).find(
+      ([eventName]) => eventName === "playback:state",
+    );
+  }
+  assert.ok(initial, "a full playback snapshot must be sent on connection");
+  assert.equal(initial[1].protocolVersion, 1);
+  assert.equal(initial[1].outputId, "global");
+  const initialRevision = initial[1].playbackRevision;
+
+  const read = await jsonRequest(baseUrl, "/api/playback");
+  assert.equal(read.response.status, 200);
+  assert.equal(read.body.playbackRevision, initialRevision);
+  const reread = await jsonRequest(baseUrl, "/api/playback");
+  assert.equal(reread.body.playbackRevision, initialRevision);
+
+  const changed = await jsonRequest(baseUrl, "/api/playback/mode", {
+    method: "PUT",
+    body: { mode: "off" },
+  });
+  assert.equal(changed.response.status, 200);
+  assert.equal(changed.body.mode, "off");
+  assert.equal(changed.body.playbackRevision, initialRevision + 1);
+
+  const events = socketEvents(await socket.poll());
+  const playbackEvents = events.filter(
+    ([eventName]) => eventName === "playback:state",
+  );
+  assert.equal(playbackEvents.length, 1);
+  assert.deepEqual(playbackEvents[0][1], changed.body);
+
+  const unchanged = await jsonRequest(baseUrl, "/api/playback/mode", {
+    method: "PUT",
+    body: { mode: "off" },
+  });
+  assert.equal(unchanged.body.playbackRevision, changed.body.playbackRevision);
+  assert.equal(
+    runtime.database
+      .prepare("SELECT revision FROM playback_state WHERE output_id = 'global'")
+      .get().revision,
+    changed.body.playbackRevision,
+  );
+});
+
 test("Socket.IO publishes playlists:changed only after successful semantic mutations", async (t) => {
   const runtime = createRuntime({
     config: testConfig(),
@@ -144,10 +204,12 @@ test("Socket.IO publishes playlists:changed only after successful semantic mutat
   });
   assert.equal(created.response.status, 201);
   let events = socketEvents(await socket.poll());
-  assert.equal(events.length, 1);
-  assert.equal(events[0][0], "playlists:changed");
-  assert.equal(events[0][1].reason, "created");
-  assert.equal(events[0][1].playlistId, created.body.id);
+  let playlistEvents = events.filter(
+    ([eventName]) => eventName === "playlists:changed",
+  );
+  assert.equal(playlistEvents.length, 1);
+  assert.equal(playlistEvents[0][1].reason, "created");
+  assert.equal(playlistEvents[0][1].playlistId, created.body.id);
 
   const duplicate = await jsonRequest(baseUrl, "/api/playlists", {
     method: "POST",
@@ -163,7 +225,10 @@ test("Socket.IO publishes playlists:changed only after successful semantic mutat
     body: { defaultDurationMs: 8_000 },
   });
   events = socketEvents(await socket.poll());
-  assert.deepEqual(events, [
+  playlistEvents = events.filter(
+    ([eventName]) => eventName === "playlists:changed",
+  );
+  assert.deepEqual(playlistEvents, [
     [
       "playlists:changed",
       {
@@ -180,8 +245,11 @@ test("Socket.IO publishes playlists:changed only after successful semantic mutat
   });
   assert.equal(second.response.status, 201);
   events = socketEvents(await socket.poll());
-  assert.equal(events.length, 1);
-  assert.equal(events[0][1].reason, "created");
+  playlistEvents = events.filter(
+    ([eventName]) => eventName === "playlists:changed",
+  );
+  assert.equal(playlistEvents.length, 1);
+  assert.equal(playlistEvents[0][1].reason, "created");
 
   const activated = await jsonRequest(
     baseUrl,
@@ -191,14 +259,20 @@ test("Socket.IO publishes playlists:changed only after successful semantic mutat
   assert.equal(activated.response.status, 200);
   assert.equal(activated.body.activation, "active");
   events = socketEvents(await socket.poll());
-  assert.equal(events.length, 1);
-  assert.equal(events[0][0], "playlists:changed");
-  assert.equal(events[0][1].reason, "activated");
-  assert.equal(events[0][1].playlistId, created.body.id);
+  playlistEvents = events.filter(
+    ([eventName]) => eventName === "playlists:changed",
+  );
+  assert.equal(playlistEvents.length, 1);
+  assert.equal(playlistEvents[0][1].reason, "activated");
+  assert.equal(playlistEvents[0][1].playlistId, created.body.id);
   assert.equal(
-    events[0][1].playbackRevision,
+    playlistEvents[0][1].playbackRevision,
     activated.body.playback.revision,
   );
+  assert.equal(
+    events.filter(([eventName]) => eventName === "playback:state").length,
+    1,
+  );
 
   const activeDelete = await jsonRequest(
     baseUrl,
@@ -208,3 +282,102 @@ test("Socket.IO publishes playlists:changed only after successful semantic mutat
   assert.equal(activeDelete.response.status, 409);
   assert.equal(activeDelete.body.error.code, "PLAYLIST_ACTIVE");
 });
+
+test("activation invalidations come from authoritative pending-state transitions", async (t) => {
+  const runtime = createRuntime({
+    config: testConfig(),
+    logger: silentLogger,
+    storage: testStorage(),
+  });
+  await runtime.start();
+  t.after(() => runtime.stop("test cleanup"));
+  const timestamp = Date.now();
+  const insertAsset = runtime.database.prepare(`
+    INSERT INTO assets (
+      id, source_sha256, display_name, original_filename, status,
+      display_sha256, display_content_type, display_byte_size,
+      display_width, display_height, created_at, updated_at
+    ) VALUES (?, ?, ?, ?, 'ready', ?, 'image/webp', 1, 1920, 1080, ?, ?)
+  `);
+  const insertPlaylist = runtime.database.prepare(`
+    INSERT INTO playlists (id, name, created_at, updated_at)
+    VALUES (?, ?, ?, ?)
+  `);
+  const insertEntry = runtime.database.prepare(`
+    INSERT INTO playlist_entries (
+      id, playlist_id, asset_id, position, created_at, updated_at
+    ) VALUES (?, ?, ?, 0, ?, ?)
+  `);
+  insertAsset.run(
+    "asset-old",
+    "a".repeat(64),
+    "Old asset",
+    "old.png",
+    "c".repeat(64),
+    timestamp,
+    timestamp,
+  );
+  insertAsset.run(
+    "asset-new",
+    "b".repeat(64),
+    "New asset",
+    "new.png",
+    "d".repeat(64),
+    timestamp,
+    timestamp,
+  );
+  insertPlaylist.run("playlist-old", "Old", timestamp, timestamp);
+  insertPlaylist.run("playlist-new", "New", timestamp, timestamp);
+  insertEntry.run(
+    "entry-old",
+    "playlist-old",
+    "asset-old",
+    timestamp,
+    timestamp,
+  );
+  insertEntry.run(
+    "entry-new",
+    "playlist-new",
+    "asset-new",
+    timestamp,
+    timestamp,
+  );
+
+  const baseUrl = `http://127.0.0.1:${runtime.address.port}`;
+  const socket = await connectPollingSocket(baseUrl);
+  t.after(() => socket.close().catch(() => {}));
+
+  const activateOld = await jsonRequest(
+    baseUrl,
+    "/api/playlists/playlist-old/activate",
+    { method: "POST" },
+  );
+  assert.equal(activateOld.body.activation, "active");
+  await socket.poll();
+
+  const requestNew = await jsonRequest(
+    baseUrl,
+    "/api/playlists/playlist-new/activate",
+    { method: "POST" },
+  );
+  assert.equal(requestNew.body.activation, "pending");
+  let invalidations = socketEvents(await socket.poll()).filter(
+    ([eventName]) => eventName === "playlists:changed",
+  );
+  assert.equal(invalidations.length, 1);
+  assert.equal(invalidations[0][1].reason, "activation_requested");
+  assert.equal(invalidations[0][1].pendingPlaylistId, "playlist-new");
+
+  const cancel = await jsonRequest(
+    baseUrl,
+    "/api/playlists/playlist-old/activate",
+    { method: "POST" },
+  );
+  assert.equal(cancel.body.activation, "already_active");
+  invalidations = socketEvents(await socket.poll()).filter(
+    ([eventName]) => eventName === "playlists:changed",
+  );
+  assert.equal(invalidations.length, 1);
+  assert.equal(invalidations[0][1].reason, "activation_canceled");
+  assert.equal(invalidations[0][1].pendingPlaylistId, null);
+});