initial Pulse implementation

server/service/PulseQueue/PulseQueue.js

@@ -0,0 +1,171 @@
+import { Pulse } from "@pulsecron/pulse";
+import { ObjectId } from "mongodb";
+
+const SERVICE_NAME = "PulseQueue";
+class PulseQueue {
+	static SERVICE_NAME = SERVICE_NAME;
+
+	constructor({ appSettings, db, pulseQueueHelper, logger }) {
+		this.db = db;
+		this.appSettings = appSettings;
+		this.pulseQueueHelper = pulseQueueHelper;
+		this.logger = logger;
+		this.init();
+	}
+
+	// ****************************************
+	// Core methods
+	// ****************************************
+	init = async () => {
+		try {
+			const mongoConnectionString =
+				this.appSettings.dbConnectionString || "mongodb://localhost:27017/uptime_db";
+			this.pulse = new Pulse({ db: { address: mongoConnectionString } });
+			await this.pulse.start();
+			this.pulse.define("monitor-job", this.pulseQueueHelper.getMonitorJob(), {});
+
+			const monitors = await this.db.getAllMonitors();
+			for (const monitor of monitors) {
+				await this.addJob(monitor._id, monitor);
+			}
+			return true;
+		} catch (error) {
+			this.logger.error({
+				message: "Failed to initialize PulseQueue",
+				service: SERVICE_NAME,
+				method: "init",
+				details: error,
+			});
+			return false;
+		}
+	};
+
+	addJob = async (monitorId, monitor) => {
+		this.logger.debug({
+			message: `Adding job ${monitor?.url ?? "No URL"}`,
+			service: SERVICE_NAME,
+			method: "addJob",
+		});
+		const intervalInSeconds = monitor.interval / 1000;
+		const job = this.pulse.create("monitor-job", {
+			monitor,
+		});
+		job.unique({ "data.monitor._id": monitor._id });
+		job.attrs.jobId = monitorId.toString();
+		job.repeatEvery(`${intervalInSeconds} seconds`);
+		await job.save();
+	};
+
+	deleteJob = async (monitor) => {
+		this.logger.debug({
+			message: `Deleting job ${monitor?.url ?? "No URL"}`,
+			service: SERVICE_NAME,
+			method: "deleteJob",
+		});
+		const result = await this.pulse.cancel({
+			"data.monitor._id": monitor._id,
+		});
+		console.log(result);
+	};
+
+	pauseJob = async (monitor) => {
+		const result = await this.pulse.disable({
+			"data.monitor._id": monitor._id,
+		});
+
+		if (result.length < 1) {
+			throw new Error("Failed to pause monitor");
+		}
+
+		this.logger.debug({
+			message: `Paused monitor ${monitor._id}`,
+			service: SERVICE_NAME,
+			method: "pauseJob",
+		});
+	};
+
+	resumeJob = async (monitor) => {
+		const result = await this.pulse.enable({
+			"data.monitor._id": monitor._id,
+		});
+
+		if (result.length < 1) {
+			throw new Error("Failed to resume monitor");
+		}
+
+		this.logger.debug({
+			message: `Resumed monitor ${monitor._id}`,
+			service: SERVICE_NAME,
+			method: "resumeJob",
+		});
+	};
+
+	shutdown = async () => {
+		this.logger.info({
+			message: "Shutting down JobQueue",
+			service: SERVICE_NAME,
+			method: "shutdown",
+		});
+		await this.pulse.stop();
+	};
+
+	// ****************************************
+	// Diagnostic methods
+	// ****************************************
+
+	getMetrics = async () => {
+		const jobs = await this.pulse.jobs();
+		const metrics = jobs.reduce(
+			(acc, job) => {
+				acc.jobs++;
+				if (job.attrs.failCount > 0 && job.attrs.failedAt >= job.attrs.lastFinishedAt) {
+					acc.failingJobs++;
+				}
+				if (job.attrs.lockedAt) {
+					acc.activeJobs++;
+				}
+				if (job.attrs.failCount > 0) {
+					acc.jobsWithFailures.push({
+						monitorId: job.attrs.data.monitor._id,
+						monitorUrl: job.attrs.data.monitor.url,
+						failCount: job.attrs.failCount,
+						failReason: job.attrs.failReason,
+					});
+				}
+				return acc;
+			},
+			{ jobs: 0, activeJobs: 0, failingJobs: 0, jobsWithFailures: [] }
+		);
+		return metrics;
+	};
+
+	getJobs = async () => {
+		const jobs = await this.pulse.jobs();
+		return jobs.map((job) => {
+			return {
+				monitorId: job.attrs.data.monitor._id,
+				monitorUrl: job.attrs.data.monitor.url,
+				lockedAt: job.attrs.lockedAt,
+				runCount: job.attrs.runCount || 0,
+				failCount: job.attrs.failCount || 0,
+				failReason: job.attrs.failReason,
+			};
+		});
+	};
+
+	flushQueues = async () => {
+		const cancelRes = await this.pulse.cancel();
+		await this.pulse.stop();
+		const initRes = await this.init();
+		return {
+			flushedJobs: cancelRes,
+			initSuccess: initRes,
+		};
+	};
+
+	obliterate = async () => {
+		await this.flushQueues();
+	};
+}
+
+export default PulseQueue;