deal with empty strings for proxyId

server/src/api/validation/monitorValidation.ts

@@ -16,6 +16,13 @@ import { DateRanges, SortOrders } from "@/types/query.js";
 
 const httpStatusCode = z.number().refine((code) => HttpStatusCodeSet.has(code), { message: "Must be a valid HTTP status code" });
 
+// The client form submits proxyId: "" when no proxy is selected, set it to undefined
+const proxyIdValidation = z
+	.string()
+	.optional()
+	.transform((value) => (value === "" ? undefined : value))
+	.refine((value) => value === undefined || /^[0-9a-f]{24}$/i.test(value), { message: "Invalid proxy ID" });
+
 export const getMonitorByIdParamValidation = z.object({
 	monitorId: z.string().min(1, "Monitor ID is required"),
 });
@@ -122,7 +129,7 @@ export const createMonitorBodyValidation = z
 		url: z.string().min(1, "URL is required"),
 		ignoreTlsErrors: z.boolean().default(false),
 		proxyMode: z.enum(ProxyModes).default("inherit"),
-		proxyId: z.string().optional(),
+		proxyId: proxyIdValidation,
 		useAdvancedMatching: z.boolean().default(false),
 		port: z.number().optional(),
 		isActive: z.boolean().optional(),
@@ -171,7 +178,7 @@ export const editMonitorBodyValidation = z
 		secret: z.string().optional(),
 		ignoreTlsErrors: z.boolean().optional(),
 		proxyMode: z.enum(ProxyModes).optional(),
-		proxyId: z.string().optional(),
+		proxyId: proxyIdValidation,
 		useAdvancedMatching: z.boolean().optional(),
 		jsonPath: z.union([z.string(), z.literal("")]).optional(),
 		expectedValue: z.union([z.string(), z.literal("")]).optional(),
@@ -233,7 +240,7 @@ const importedMonitorSchema = z
 		type: z.enum(MonitorTypes, "Invalid monitor type"),
 		ignoreTlsErrors: z.boolean().default(false),
 		proxyMode: z.enum(ProxyModes).default("inherit"),
-		proxyId: z.string().optional(),
+		proxyId: proxyIdValidation,
 		useAdvancedMatching: z.boolean().default(false),
 		jsonPath: z.union([z.string(), z.literal("")]).optional(),
 		expectedValue: z.union([z.string(), z.literal("")]).optional(),
@@ -306,7 +313,7 @@ export const monitorResponseSchema = z
 		statusWindowThreshold: z.number(),
 		ignoreTlsErrors: z.boolean(),
 		proxyMode: z.enum(ProxyModes),
-		proxyId: z.string().optional(),
+		proxyId: proxyIdValidation,
 		useAdvancedMatching: z.boolean(),
 		jsonPath: z.string().optional(),
 		expectedValue: z.string().optional(),

server/src/domain/monitors/monitor.repository.interface.ts

@@ -34,7 +34,7 @@ export interface IMonitorsRepository {
 	findByIds(monitorIds: string[], options?: { recentChecks?: RecentChecksMode }): Promise<Monitor[]>;
 
 	// update
-	updateById(monitorId: string, teamId: string, updates: Partial<Monitor>): Promise<Monitor>;
+	updateById(monitorId: string, teamId: string, updates: Partial<Monitor>, options?: { unsetProxyId?: boolean }): Promise<Monitor>;
 	updateByIds(monitorIds: string[], teamId: string, updates: Partial<Monitor>, excludeStatuses?: MonitorStatus[]): Promise<number>;
 	updateStatusWindowAndChecks(
 		monitorId: string,

server/src/domain/monitors/monitor.repository.mongo.ts

@@ -177,16 +177,14 @@ class MongoMonitorsRepository implements IMonitorsRepository {
 		return count;
 	};
 
-	updateById = async (monitorId: string, teamId: string, patch: Partial<Monitor>) => {
-		const updatedMonitor = await MonitorModel.findOneAndUpdate(
-			{ _id: monitorId, teamId },
-			{
-				$set: {
-					...patch,
-				},
-			},
-			{ new: true, runValidators: true }
-		);
+	updateById = async (monitorId: string, teamId: string, patch: Partial<Monitor>, options?: { unsetProxyId?: boolean }) => {
+		const fields: Partial<Monitor> = { ...patch };
+		const update: Record<string, unknown> = { $set: fields };
+		if (options?.unsetProxyId) {
+			delete fields.proxyId;
+			update.$unset = { proxyId: "" };
+		}
+		const updatedMonitor = await MonitorModel.findOneAndUpdate({ _id: monitorId, teamId }, update, { new: true, runValidators: true });
 		if (!updatedMonitor) {
 			throw new AppError({ message: `Failed to update monitor with id ${monitorId}`, status: 500 });
 		}

server/src/domain/monitors/monitor.service.ts

@@ -133,6 +133,10 @@ export class MonitorService implements IMonitorService {
 	}
 
 	createMonitor = async (teamId: string, userId: string, body: Monitor): Promise<void> => {
+		// proxyId is only needed in custom mode
+		if (body.proxyMode !== "custom") {
+			delete body.proxyId;
+		}
 		const monitor = await this.monitorsRepository.create(body, teamId, userId);
 		if (!monitor) {
 			throw new AppError({ message: "Failed to create monitor", status: 500, service: SERVICE_NAME, method: "createMonitor" });
@@ -375,7 +379,12 @@ export class MonitorService implements IMonitorService {
 	};
 
 	editMonitor = async ({ teamId, monitorId, body }: { teamId: string; monitorId: string; body: Partial<Monitor> }) => {
-		const editedMonitor = await this.monitorsRepository.updateById(monitorId, teamId, body);
+		// Moving off custom mode orphans the stored proxyId. Unset it so the stale reference doesn't block deleting that proxy
+		const unsetProxyId = body.proxyMode !== undefined && body.proxyMode !== "custom";
+		if (unsetProxyId) {
+			delete body.proxyId;
+		}
+		const editedMonitor = await this.monitorsRepository.updateById(monitorId, teamId, body, { unsetProxyId });
 		await this.scheduler.updateJob(editedMonitor);
 		return editedMonitor;
 	};