refactor: Improve error handling in Semaphore.lock()

This commit refactors the Semaphore.lock() function in the MonitorStatusTimelineService and Monitor API files to improve error handling. It adds try-catch blocks around the lock() function calls and logs any errors that occur using the logger. This change ensures that errors during the locking process are properly handled and logged, preventing potential issues with mutex locking.

CommonServer/Infrastructure/Semaphore.ts

@@ -1,16 +1,14 @@
 import Redis, { ClientType } from "./Redis";
-import Dictionary from "Common/Types/Dictionary";
-import ObjectID from "Common/Types/ObjectID";
 import { Mutex } from "redis-semaphore";
 
-export default class Semaphore {
-  private static mutexDictionary: Dictionary<Mutex> = {};
+export type SemaphoreMutex = Mutex;
 
+export default class Semaphore {
   // returns the mutex id
   public static async lock(data: {
     key: string;
     lockTimeout?: number;
-  }): Promise<ObjectID> {
+  }): Promise<SemaphoreMutex> {
     if (!data.lockTimeout) {
       data.lockTimeout = 1000;
     }
@@ -23,30 +21,16 @@ export default class Semaphore {
       throw new Error("Redis client is not connected");
     }
 
-    const mutex: Mutex = new Mutex(client, key, {
+    const mutex: SemaphoreMutex = new Mutex(client, key, {
       lockTimeout: data.lockTimeout,
     });
 
     await mutex.acquire();
 
-    const mutexId: ObjectID = ObjectID.generate();
-
-    // add to the dictionary
-    this.mutexDictionary[mutexId.toString()] = mutex;
-
-    return mutexId;
+    return mutex;
   }
 
-  public static async release(mutexId: ObjectID): Promise<void> {
-    const mutex: Mutex | undefined = this.mutexDictionary[mutexId.toString()];
-
-    if (!mutex) {
-      return; // already released
-    }
-
+  public static async release(mutex: SemaphoreMutex): Promise<void> {
     await mutex.release();
-
-    // remove from the dictionary
-    delete this.mutexDictionary[mutexId.toString()];
   }
 }

CommonServer/Services/MonitorStatusTimelineService.ts

@@ -1,5 +1,5 @@
 import PostgresDatabase from "../Infrastructure/PostgresDatabase";
-import Semaphore from "../Infrastructure/Semaphore";
+import Semaphore, { SemaphoreMutex } from "../Infrastructure/Semaphore";
 import CreateBy from "../Types/Database/CreateBy";
 import DeleteBy from "../Types/Database/DeleteBy";
 import { OnCreate, OnDelete } from "../Types/Database/Hooks";
@@ -29,10 +29,10 @@ export class Service extends DatabaseService<MonitorStatusTimeline> {
       throw new BadDataException("monitorId is null");
     }
 
-    let mutexId: ObjectID | null = null;
+    let mutex: SemaphoreMutex | null = null;
 
     try {
-      mutexId = await Semaphore.lock({
+      mutex = await Semaphore.lock({
         key: createBy.data.monitorId.toString(),
       });
     } catch (e) {
@@ -98,7 +98,7 @@ export class Service extends DatabaseService<MonitorStatusTimeline> {
       createBy,
       carryForward: {
         lastMonitorStatusTimelineId: lastMonitorStatusTimeline?.id || null,
-        mutexId: mutexId,
+        mutex: mutex,
       },
     };
   }
@@ -139,9 +139,9 @@ export class Service extends DatabaseService<MonitorStatusTimeline> {
       props: onCreate.createBy.props,
     });
 
-    if (onCreate.carryForward.mutexId) {
-      const mutexId: ObjectID = onCreate.carryForward.mutexId;
-      await Semaphore.release(mutexId);
+    if (onCreate.carryForward.mutex) {
+      const mutex: SemaphoreMutex = onCreate.carryForward.mutex;
+      await Semaphore.release(mutex);
     }
 
     return createdItem;

Ingestor/API/Monitor.ts

@@ -10,7 +10,9 @@ import BadDataException from "Common/Types/Exception/BadDataException";
 import { JSONObject } from "Common/Types/JSON";
 import ObjectID from "Common/Types/ObjectID";
 import PositiveNumber from "Common/Types/PositiveNumber";
-import Semaphore from "CommonServer/Infrastructure/Semaphore";
+import Semaphore, {
+  SemaphoreMutex,
+} from "CommonServer/Infrastructure/Semaphore";
 import ClusterKeyAuthorization from "CommonServer/Middleware/ClusterKeyAuthorization";
 import MonitorProbeService from "CommonServer/Services/MonitorProbeService";
 import Query from "CommonServer/Types/Database/Query";
@@ -196,7 +198,7 @@ router.post(
     res: ExpressResponse,
     next: NextFunction,
   ): Promise<void> => {
-    let mutexId: ObjectID | null = null;
+    let mutex: SemaphoreMutex | null = null;
 
     try {
       const data: JSONObject = req.body;
@@ -224,7 +226,7 @@ router.post(
       }
 
       try {
-        mutexId = await Semaphore.lock({
+        mutex = await Semaphore.lock({
           key: probeId.toString(),
         });
       } catch (err) {
@@ -287,8 +289,12 @@ router.post(
         });
       }
 
-      if (mutexId) {
-        await Semaphore.release(mutexId);
+      if (mutex) {
+        try {
+          await Semaphore.release(mutex);
+        } catch (err) {
+          logger.error(err);
+        }
       }
 
       const monitors: Array<Monitor> = monitorProbes
@@ -321,8 +327,8 @@ router.post(
       );
     } catch (err) {
       try {
-        if (mutexId) {
-          await Semaphore.release(mutexId);
+        if (mutex) {
+          await Semaphore.release(mutex);
         }
       } catch (err) {
         logger.error(err);