TypeScript!

lib/cluster.ts

@@ -0,0 +1,95 @@
+/**
+ * Copyright 2013-2018  Zaid Abdulla
+ *
+ * This file is part of GenieACS.
+ *
+ * GenieACS is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * GenieACS is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with GenieACS.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import cluster from "cluster";
+import { cpus } from "os";
+import * as logger from "./logger";
+
+let respawnTimestamp = 0;
+let tooManyCrashesTimestamp = 0;
+
+function restartWorker(worker, code, signal): void {
+  const msg = {
+    message: "Worker died",
+    pid: worker.process.pid,
+    exitCode: null,
+    signal: null
+  };
+
+  if (code != null) msg.exitCode = code;
+
+  if (signal != null) msg.signal = signal;
+
+  logger.error(msg);
+
+  const now = Date.now();
+  respawnTimestamp = Math.max(now, respawnTimestamp + 2000);
+  if (respawnTimestamp === now) {
+    tooManyCrashesTimestamp = now;
+    cluster.fork();
+    return;
+  }
+
+  if (now - tooManyCrashesTimestamp > 60000) {
+    process.exitCode = 1;
+    cluster.removeListener("exit", restartWorker);
+    for (const pid in cluster.workers) cluster.workers[pid].kill();
+
+    logger.error({
+      message: "Too many crashes, exiting",
+      pid: process.pid
+    });
+    return;
+  }
+
+  setTimeout(() => {
+    if (process.exitCode) return;
+    cluster.fork();
+  }, respawnTimestamp - now);
+}
+
+export function start(workerCount, servicePort, serviceAddress): void {
+  cluster.on("listening", (worker, address) => {
+    if (
+      (address.addressType === 4 || address.addressType === 6) &&
+      address.address === serviceAddress &&
+      address.port === servicePort
+    ) {
+      logger.info({
+        message: "Worker listening",
+        pid: worker.process.pid,
+        address: address.address,
+        port: address.port
+      });
+    }
+  });
+
+  cluster.on("exit", restartWorker);
+
+  if (!workerCount) workerCount = Math.max(2, cpus().length);
+
+  for (let i = 0; i < workerCount; ++i) cluster.fork();
+}
+
+export function stop(): void {
+  cluster.removeListener("exit", restartWorker);
+  for (const pid in cluster.workers) cluster.workers[pid].kill();
+}
+
+export const worker = cluster.worker;