Files
Nodecast/server/services/googleCastAdapter.js
blomios 5ee07570e0 feat(cast): add server-managed Google Cast playback (#34)
Add server-side Google Cast discovery and sessions, signed cast media URLs, browser device picker integration, and deployment documentation.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-10-06 22:40:17 +02:00

132 lines
6.3 KiB
JavaScript

const crypto = require('crypto');
function defaultDependencies() {
return { Bonjour: require('bonjour-service'), castClient: require('chromecast-client') };
}
function firstAddress(service) {
return (service.addresses || []).find(address => /^\d{1,3}(?:\.\d{1,3}){3}$/.test(address)) ||
service.addresses?.[0] || service.referer?.address || service.host || null;
}
function normalizeDevice(service) {
const txt = service.txt || {};
const model = String(txt.md || txt.model || '').trim();
const descriptor = `${model} ${service.name || ''}`.toLowerCase();
const host = firstAddress(service);
return {
id: String(txt.id || service.fqdn || service.name || `${host}:${service.port || 8009}`),
name: String(txt.fn || service.name || model || 'Google Cast device'),
type: /android tv|google tv|chromecast built-in|bravia|shield/.test(descriptor) ? 'android_tv_cast' : 'google_cast',
ready: Boolean(host),
host,
port: Number(service.port || 8009),
model: model || null
};
}
function unwrap(result, castClient) {
if (result && typeof result.unwrapAndThrow === 'function') return result.unwrapAndThrow();
if (castClient.Result?.unwrapAndThrow) return castClient.Result.unwrapAndThrow(result);
if (result && result.isOk === false) throw result.value;
if (result && result.isOk === true) return result.value;
return result;
}
function createGoogleCastAdapter(options = {}) {
let dependencies;
try { dependencies = options.dependencies || defaultDependencies(); }
catch (error) {
return {
async discover() { return []; },
async startSession() {
throw Object.assign(new Error(`Google Cast support is unavailable: ${error.message}`), { code: 'CAST_ADAPTER_UNAVAILABLE' });
}
};
}
const { Bonjour, castClient } = dependencies;
const discoveryTimeoutMs = Number(options.discoveryTimeoutMs || 1500);
const connectTimeoutMs = Number(options.connectTimeoutMs || 8000);
const sessions = new Map();
async function discover() {
const bonjour = new Bonjour(undefined, () => {});
const found = new Map();
let browser;
let timer;
try {
await new Promise(resolve => {
timer = setTimeout(resolve, discoveryTimeoutMs);
browser = bonjour.find({ type: 'googlecast', protocol: 'tcp' }, service => {
const device = normalizeDevice(service);
if (device.host) found.set(device.id, device);
});
browser?.on?.('error', resolve);
});
return [...found.values()].sort((left, right) => left.name.localeCompare(right.name));
} catch (error) {
throw Object.assign(new Error(`Google Cast discovery failed: ${error.message}`), { code: 'CAST_DISCOVERY_FAILED' });
} finally {
clearTimeout(timer);
try { browser?.stop?.(); } catch { /* best effort */ }
try { bonjour.destroy(); } catch { /* best effort */ }
}
}
async function startSession({ device, mediaUrl, media = {} }) {
if (!device?.host) throw Object.assign(new Error('Google Cast device has no reachable host'), { code: 'CAST_DEVICE_UNREACHABLE' });
let client;
let controller;
try {
client = await castClient.connect({ host: device.host, port: device.port || 8009, timeout: connectTimeoutMs });
controller = unwrap(await castClient.DefaultMediaApp.launchAndJoin({ client }), castClient);
const status = unwrap(await controller.load({
media: {
contentId: mediaUrl,
contentType: media.contentType || 'application/vnd.apple.mpegurl',
streamType: media.streamType || 'LIVE',
metadata: media.metadata || { metadataType: 0, title: media.title || 'Nodecast TV' }
},
autoplay: media.autoplay !== false,
currentTime: Number(media.currentTime || 0)
}), castClient);
const sessionId = crypto.randomUUID();
sessions.set(sessionId, { client, controller, device });
return { sessionId, state: String(status?.playerState || 'PLAYING').toLowerCase(), currentTime: Number(status?.currentTime || 0) };
} catch (error) {
try { controller?.dispose?.(); } catch { /* best effort */ }
try { client?.close?.(); } catch { /* best effort */ }
throw Object.assign(new Error(`Unable to start Google Cast playback: ${error.message}`), { code: 'CAST_START_FAILED' });
}
}
async function command({ session, action, ...payload }) {
const active = sessions.get(session.sessionId || session.id);
if (!active) throw Object.assign(new Error('Google Cast connection is no longer active'), { code: 'CAST_SESSION_DISCONNECTED' });
if (action === 'volume') throw Object.assign(new Error('Volume control is unavailable for this Cast adapter'), { code: 'CAST_CONTROL_UNAVAILABLE' });
const method = active.controller[action];
if (typeof method !== 'function') throw Object.assign(new Error(`Unsupported Cast command: ${action}`), { code: 'CAST_CONTROL_UNAVAILABLE' });
const argument = action === 'seek'
? (payload.currentTime !== undefined ? { currentTime: Number(payload.currentTime) } : { relativeTime: Number(payload.relativeTime || 0) })
: undefined;
const status = unwrap(await (argument ? method(argument) : method()), castClient);
return { state: String(status?.playerState || action).toLowerCase(), currentTime: Number(status?.currentTime || 0) };
}
async function stopSession(session) {
const id = session.sessionId || session.id;
const active = sessions.get(id);
if (!active) return;
try { unwrap(await active.controller.stop(), castClient); } finally {
try { active.controller.dispose?.(); } catch { /* best effort */ }
try { active.client.close?.(); } catch { /* best effort */ }
sessions.delete(id);
}
}
return { command, discover, startSession, stopSession };
}
module.exports = { createGoogleCastAdapter, normalizeDevice };