feat: check if job state update was successful before running a job

this stops processing jobs when they got removed in the meantime from the database

src/Job.ts

@@ -377,8 +377,14 @@ export class Job<DATA = unknown | void> {
 			log('[%s:%s] has failed [%s]', this.attrs.name, this.attrs._id, error.message);
 		} finally {
 			this.attrs.lockedAt = undefined;
-			await this.agenda.db.saveJobState(this);
-			log('[%s:%s] was saved successfully to MongoDB', this.attrs.name, this.attrs._id);
+			try {
+				await this.agenda.db.saveJobState(this);
+				log('[%s:%s] was saved successfully to MongoDB', this.attrs.name, this.attrs._id);
+			} catch (err) {
+				// in case this fails, we ignore it
+				// this can e.g. happen if the job gets removed during the execution
+				log('[%s:%s] was not saved to MongoDB', this.attrs.name, this.attrs._id, err);
+			}
 
 			this.agenda.emit('complete', this);
 			this.agenda.emit(`complete:${this.attrs.name}`, this);

src/JobDbRepository.ts

@@ -256,12 +256,18 @@ export class JobDbRepository {
 
 		log('[job %s] save job state: \n%O', id, $set);
 
-		await this.collection.updateOne(
+		const result = await this.collection.updateOne(
 			{ _id: id, name: job.attrs.name },
 			{
 				$set
 			}
 		);
+
+		if (!result.acknowledged || result.matchedCount !== 1) {
+			throw new Error(
+				`job ${id} (name: ${job.attrs.name}) cannot be updated in the database, maybe it does not exist anymore?`
+			);
+		}
 	}
 
 	/**

test/job.test.ts

@@ -1601,4 +1601,44 @@ describe('Job', () => {
 
 		expect(await job.isRunning()).to.be.equal(true);
 	});
+
+	it('should not run job if is has been removed', async () => {
+		let executed = false;
+		agenda.define('test', async () => {
+			executed = true;
+		});
+
+		const job = new Job(agenda, {
+			name: 'test',
+			type: 'normal'
+		});
+		job.schedule('in 1 second');
+		await job.save();
+
+		await agenda.start();
+
+		// wait till it's locked (Picked up by the event processor)
+		const jobStarted = await agenda.db.getJobs({ name: 'test' });
+		expect(jobStarted[0].lockedAt).to.not.equal(null);
+
+		await job.remove();
+
+		let error;
+		const completed = new Promise<void>(resolve => {
+			agenda.on('error', err => {
+				error = err;
+				resolve();
+			});
+		});
+
+		await Promise.race([
+			new Promise(resolve => {
+				setTimeout(resolve, 1000);
+			}),
+			completed
+		]);
+
+		expect(executed).to.be.equal(false);
+		expect(error?.message).to.includes('(name: test) cannot be updated in the database');
+	});
 });