Split logs by date

Move the default location of the log files into a configurable logs
folder and split the written logs up by UTC date to more easily allow
deleting of old logs to be performed.  The log rotation is implemented
by winston-daily-rotate-file.

The old log format will automatically be migrated to the new format and
location if the target folder for the new logs don't yet exists.

packages/lib/logging_utils.js

@@ -1,4 +1,7 @@
 "use strict";
+const events = require("events");
+const fs = require("fs-extra");
+const path = require("path");
 const winston = require("winston");
 const Transport = require("winston-transport");
 const { LEVEL, MESSAGE } = require("triple-beam");
@@ -6,6 +9,7 @@ const chalk = require("chalk");
 
 const libLink = require("./link");
 const libErrors = require("./errors");
+const libStream = require("./stream");
 
 
 /**
@@ -121,10 +125,67 @@ class LinkTransport extends Transport {
 	}
 }
 
+async function migrateLogs(log, directory, pattern) {
+	const dateRegExp = /^\d{4}-\d{2}-\d{2}/;
+	let lineStream = new libStream.LineSplitter({ readableObjectMode: true });
+	let fileStream = fs.createReadStream(log);
+	fileStream.pipe(lineStream);
+
+	let currentDate = null;
+	let output = null;
+
+	async function switchOutput(newOutputPath) {
+		if (output) {
+			output.end();
+			await events.once(output, "close");
+		}
+
+		output = fs.createWriteStream(newOutputPath, { flags: "ax" });
+		try {
+			await events.once(output, "open");
+			// eslint-disable-next-line no-console
+			console.log(`writing ${newOutputPath}`);
+		} catch (err) {
+			if (err.code === "EEXIST") {
+				// eslint-disable-next-line no-console
+				console.warn(`Discarding logs for ${newDate} due to target logfile already existing`);
+				output = null;
+			} else {
+				throw err;
+			}
+		}
+	}
+
+	for await (let line of lineStream) {
+		let info = {};
+		try {
+			info = JSON.parse(line);
+		} catch (err) {
+			// Ignore
+		}
+
+		if (typeof info.timestamp === "string" && dateRegExp.test(info.timestamp)) {
+			let newDate = info.timestamp.slice(0, 10);
+			// Only update date forward in time.
+			if (newDate !== currentDate && (!currentDate || newDate > currentDate)) {
+				await switchOutput(path.join(directory, pattern.replace("%DATE%", newDate)));
+				currentDate = newDate;
+			}
+		}
+
+		if (output) {
+			if (!output.write(Buffer.concat([line, Buffer.from("\n")]))) {
+				await events.once(output, "drain");
+			}
+		}
+	}
+}
+
 
 module.exports = {
 	TerminalFormat,
 	LinkTransport,
+	migrateLogs,
 
 	// for testing only
 	_formatServerOutput: formatServerOutput,

packages/master/master.js

@@ -22,6 +22,7 @@ const setBlocking = require("set-blocking");
 const yargs = require("yargs");
 const util = require("util");
 const winston = require("winston");
+require("winston-daily-rotate-file");
 const jwt = require("jsonwebtoken");
 
 // homebrew modules
@@ -189,6 +190,12 @@ async function initialize() {
 			choices: ["none"].concat(Object.keys(levels)),
 			type: "string",
 		})
+		.option("log-directory", {
+			nargs: 1,
+			describe: "Directory to place logs in",
+			default: "logs",
+			type: "string",
+		})
 		.option("config", {
 			nargs: 1,
 			describe: "master config file to use",
@@ -227,20 +234,45 @@ async function initialize() {
 		.argv
 	;
 
+	{
+		// Migration from alpha-10 single file logs, note that we can't use
+		// the logger here as it's not initalized yet.
+		/* eslint-disable no-console */
+		let clusterLogDirectory = path.join(parameters.args.logDirectory, "cluster");
+		if (!await fs.pathExists(clusterLogDirectory) && await fs.pathExists("cluster.log")) {
+			console.log("Migrating cluster log...");
+			await fs.ensureDir(clusterLogDirectory);
+			await libLoggingUtils.migrateLogs("cluster.log", clusterLogDirectory, "cluster-%DATE%.log");
+			console.log("Migration complete, you should delete cluster.log now");
+		}
+
+		let masterLogDirectory = path.join(parameters.args.logDirectory, "master");
+		if (!await fs.pathExists(masterLogDirectory) && await fs.pathExists("master.log")) {
+			console.log("Migrating master log...");
+			await fs.ensureDir(masterLogDirectory);
+			await libLoggingUtils.migrateLogs("master.log", masterLogDirectory, "master-%DATE%.log");
+			console.log("Migration complete, you should delete master.log now");
+		}
+		/* eslint-enable no-console */
+	}
+
 	// Combined log stream of the whole cluster.
 	parameters.clusterLogger = winston.createLogger({
 		format: winston.format.json(),
 		level: "verbose",
 		levels,
 	});
-	parameters.clusterLogger.add(new winston.transports.File({
-		filename: "cluster.log",
+	parameters.clusterLogger.add(new winston.transports.DailyRotateFile({
+		filename: "cluster-%DATE%.log",
+		utc: true,
+		dirname: path.join(parameters.args.logDirectory, "cluster"),
 	}));
 
 	// Log stream for the master server.
-	logger.add(new winston.transports.File({
+	logger.add(new winston.transports.DailyRotateFile({
 		format: winston.format.json(),
-		filename: "master.log",
+		filename: "master-%DATE%.log",
+		dirname: path.join(parameters.args.logDirectory, "master"),
 	}));
 	logger.add(new winston.transports.Stream({
 		stream: parameters.clusterLogger,

packages/master/package.json

@@ -28,6 +28,7 @@
     "jszip": "^3.2.2",
     "set-blocking": "^2.0.0",
     "winston": "^3.3.3",
+    "winston-daily-rotate-file": "^4.5.5",
     "ws": "^7.2.3",
     "yargs": "^14.2.0"
   },

packages/slave/package.json

@@ -24,6 +24,7 @@
     "pidusage": "^2.0.18",
     "set-blocking": "^2.0.0",
     "winston": "^3.3.3",
+    "winston-daily-rotate-file": "^4.5.5",
     "yargs": "^14.2.0"
   },
   "publishConfig": {

packages/slave/slave.js

@@ -23,6 +23,7 @@ const phin = require("phin");
 const util = require("util");
 const version = require("./package").version;
 const winston = require("winston");
+require("winston-daily-rotate-file");
 
 // internal libraries
 const libFileOps = require("@clusterio/lib/file_ops");
@@ -1734,6 +1735,12 @@ async function startSlave() {
 			choices: ["none"].concat(Object.keys(levels)),
 			type: "string",
 		})
+		.option("log-directory", {
+			nargs: 1,
+			describe: "Directory to place logs in",
+			default: "logs",
+			type: "string",
+		})
 		.option("config", {
 			nargs: 1,
 			describe: "slave config file to use",
@@ -1754,11 +1761,25 @@ async function startSlave() {
 		.argv
 	;
 
-	logger.add(new winston.transports.File({
-		format: winston.format.combine(
-			winston.format.json(),
-		),
-		filename: "slave.log",
+	{
+		// Migration from alpha-10 single file logs, note that we can't use
+		// the logger here as it's not initalized yet.
+		/* eslint-disable no-console */
+		let slaveLogDirectory = path.join(args.logDirectory, "slave");
+		if (!await fs.pathExists(slaveLogDirectory) && await fs.pathExists("slave.log")) {
+			console.log("Migrating slave log...");
+			await fs.ensureDir(slaveLogDirectory);
+			await libLoggingUtils.migrateLogs("slave.log", slaveLogDirectory, "slave-%DATE%.log");
+			console.log("Migration complete, you should delete slave.log now");
+		}
+		/* eslint-enable no-console */
+	}
+
+	logger.add(new winston.transports.DailyRotateFile({
+		format: winston.format.json(),
+		filename: "slave-%DATE%.log",
+		utc: true,
+		dirname: path.join(args.logDirectory, "slave"),
 	}));
 	if (args.logLevel !== "none") {
 		logger.add(new ConsoleTransport({