From 67806c94b15290d4add6922f65db6a80624b8bb9 Mon Sep 17 00:00:00 2001
From: egeoztass <egeoztas@sabanciuniv.edu>
Date: Mon, 7 Sep 2026 12:31:07 +0200
Subject: [PATCH] fix: return the created monitor from createMonitor

The controller writes the service's return value into the response, but
createMonitor was typed Promise<void> and returned nothing, so every
successful POST /monitors answered data: null and callers had no way to
read the new monitor's id.

Fixes #3917

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01D7eViZ2Np5ZpWUYNoRhmAt
---
 server/src/domain/monitors/monitor.service.ts    | 5 +++--
 server/test/unit/services/monitorService.test.ts | 5 +++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/server/src/domain/monitors/monitor.service.ts b/server/src/domain/monitors/monitor.service.ts
index 43cba16d8..9e4f7f6e5 100644
--- a/server/src/domain/monitors/monitor.service.ts
+++ b/server/src/domain/monitors/monitor.service.ts
@@ -60,7 +60,7 @@ const computeRestartsInRange = (aggregate: DockerContainerStatsBucket[]): number
 
 export interface IMonitorService {
 	// create
-	createMonitor(teamId: string, userId: string, body: Partial<Monitor>): Promise<void>;
+	createMonitor(teamId: string, userId: string, body: Partial<Monitor>): Promise<Monitor>;
 	createMonitors(monitors: Array<Monitor>): Promise<Monitor[] | null>;
 	addDemoMonitors(args: { userId: string; teamId: string }): Promise<Monitor[]>;
 
@@ -180,7 +180,7 @@ export class MonitorService implements IMonitorService {
 		this.incidentsRepository = incidentsRepository;
 	}
 
-	createMonitor = async (teamId: string, userId: string, body: Monitor): Promise<void> => {
+	createMonitor = async (teamId: string, userId: string, body: Monitor): Promise<Monitor> => {
 		// proxyId is only needed in custom mode
 		if (body.proxyMode !== "custom") {
 			delete body.proxyId;
@@ -191,6 +191,7 @@ export class MonitorService implements IMonitorService {
 		}
 
 		this.scheduler.addJob(monitor.id, monitor);
+		return monitor;
 	};
 
 	createMonitors = async (monitors: Array<Monitor>): Promise<Monitor[] | null> => {
diff --git a/server/test/unit/services/monitorService.test.ts b/server/test/unit/services/monitorService.test.ts
index 1bb4b3423..d3f5dd1a7 100644
--- a/server/test/unit/services/monitorService.test.ts
+++ b/server/test/unit/services/monitorService.test.ts
@@ -122,16 +122,17 @@ const createService = (
 
 describe("MonitorService", () => {
 	describe("createMonitor", () => {
-		it("creates a monitor and adds a job", async () => {
+		it("creates a monitor, adds a job and returns the created document", async () => {
 			const monitorsRepository = createMonitorsRepositoryMock();
 			const monitor = makeMonitor();
 			(monitorsRepository.create as jest.Mock).mockResolvedValue(monitor);
 			const { service, jobQueue } = createService({ monitorsRepository });
 
-			await service.createMonitor(TEAM_ID, USER_ID, monitor as any);
+			const result = await service.createMonitor(TEAM_ID, USER_ID, monitor as any);
 
 			expect(monitorsRepository.create).toHaveBeenCalledWith(monitor, TEAM_ID, USER_ID);
 			expect(jobQueue.addJob).toHaveBeenCalledWith(MONITOR_ID, monitor);
+			expect(result).toBe(monitor);
 		});
 
 		it("strips a stray proxyId when proxyMode is not custom", async () => {