persist playlists

index.js

@@ -12,14 +12,6 @@ var server = app.listen(process.env.PORT || 8080, process.env.ADDR);
 
 app.use(morgan(`:date[iso] :remote-addr :method :url ":req[user-agent]" :referrer`));
 
-app.get("/playlist", async (req, res) => {
-	var channel = req.query.channel || "default";
-	if (/[^a-z0-9-~]/.test(channel)) {
-		return res.sendStatus(400);
-	}
-	res.send(await getPlaylist(channel));
-});
-
 app.get("/channels", async (req, res) => {
 	res.send(await getChannels());
 });
@@ -31,23 +23,28 @@ app.get("/newchannel", async (req, res, next) => {
 	var number = req.query.number;
 	if (number < 1 || number > 1000) return res.sendStatus(400);
 	var code = `${search.replaceAll(' ', '-')}~${number}`;
-	var file = `channels/${code}.json`;
 	try {
-		await fs.access(file);
-		return res.sendStatus(409);
-	} catch(error) {
-		if (error.code != "ENOENT") next(error);
+		await fs.mkdir(`public/channels/${code}`);
+	} catch (error) {
+		if (error.code == "EEXIST") {
+			res.redirect("/"+code);
+		} else {
+			next(error);
+		}
+		return;
 	}
-	execFile("python3", ["getvideos.py", search, number, file], (error, stdout, stderr) => {
+	execFile("python3", ["getvideos.py", search, number, `public/channels/${code}/dump.json`], (error, stdout, stderr) => {
 		if (error) next(error);
-		//res.type("text").send(code);
-		res.redirect("/"+code);
+		console.log({stdout, stderr});
+		generatePlaylist(channel).then(() => {
+			res.redirect("/"+code);
+		});
 	});
 });
 
 app.use(/^\/([a-z0-9-~]+)$/, (req, res, next) => {
 	var channel = req.params[0];
-	fs.access(`channels/${channel}.json`).then(() => {
+	fs.access(`public/channels/${channel}`).then(() => {
 		//req.url = "/index.html"; //??
 		res.sendFile("index.html", {root: "public"});
 	}).catch(() => {
@@ -60,40 +57,47 @@ app.use(express.static("public"));
 
 
 
-
-
-var playlists = {};
-
-async function getPlaylist(channel = "default") {
-	var playlist = playlists[channel];
-	if (!playlist || Date.now() > playlist.timestamp + playlist.totalDuration*1000) {
-		playlist = await generatePlaylist(channel);
-		playlists[channel] = playlist;
-	}
-	return playlist;
-}
-
-async function generatePlaylist(channel = "default") {
-	var videos = JSON.parse(await fs.readFile(`channels/${channel}.json`, "utf8")).entries;
-	videos = videos.map(v => ({
+async function generatePlaylist(channel) {
+	var dump = JSON.parse(await fs.readFile(`public/channels/${channel}/dump.json`, "utf8"));
+	var videos = dump.entries.map(v => ({
 		id: v.id,
 		duration: v.duration,
 		title: v.title
 	}));
-
 	shuffle(videos);
-
-	return {
+	var playlist = {
 		videos,
 		timestamp: Date.now(),
 		totalDuration: videos.reduce((td, v) => td + v.duration, 0)
-	}
+	};
+	await fs.writeFile(`public/channels/${channel}/playlist.json`, JSON.stringify(playlist));
+	var expiresIn = playlist.timestamp + playlist.totalDuration*1000 - Date.now();
+	setTimeout(generatePlaylist, expiresIn);
+	console.log(`generated new playlist for ${channel} expires in ${expiresIn/1000}s`);
 }
 
+(async function () {
+	var channelDirs = await fs.readdir("public/channels");
+	for (var channel of channelDirs) {
+		try {
+			try {
+				var playlist = JSON.parse(await fs.readFile(`public/channels/${channel}/playlist.json`, "utf8"));
+			} catch (error) {
+				if (error.code != "ENOENT") console.error(error.stack);
+			}
+			if (!playlist || Date.now() > playlist.timestamp + playlist.totalDuration*1000) {
+				await generatePlaylist(channel);
+			}
+		} catch (error) {
+			console.error(error.stack);
+		}
+	}
+})();
+
+
 async function getChannels() {
-	var channels = await fs.readdir("channels");
+	var channels = await fs.readdir("public/channels");
 	channels = channels.map(c => {
-		c = c.replace(".json", "");
 		var n = [...wss.clients].reduce((num, ws) => ws.channel == c ? num + 1 : num, 0);
 		return [c, n];
 	});

public/index.html

@@ -235,7 +235,7 @@
 
 		async function nowPlaying() {
 			if (!playlist || Date.now() > playlist.timestamp + playlist.totalDuration*1000) {
-				playlist = await fetch("playlist?channel=" + channel).then(res => res.json());
+				playlist = await fetch(`channels/${channel}/playlist.json`).then(res => res.json());
 			}
 			for (var i = 0, pastDurations = 0; i < playlist.videos.length; i++) {
 				var video = playlist.videos[i];