Merge pull request #36 from brendan-ch/feat/persistent-data-storage-for-notifications

docker-compose.yml

@@ -33,7 +33,7 @@ services:
     depends_on:
       - redis-no-persistence
     environment:
-      <<: *common-server-environment
+      REDIS_URL: redis://redis-no-persistence:6379
 
     volumes:
       - .:/usr/src/app
@@ -44,10 +44,11 @@ services:
     depends_on:
       - redis-no-persistence
     environment:
-      <<: *common-server-environment
+      REDIS_URL: redis://redis-no-persistence:6379
 
     volumes:
       - .:/usr/src/app
+
   redis:
     image: redis:alpine
     ports:

package-lock.json

@@ -20,6 +20,7 @@
         "@jest/globals": "^29.7.0",
         "@types/jsonwebtoken": "^9.0.8",
         "@types/node": "^22.10.2",
+        "@types/redis": "^4.0.11",
         "jest": "^29.7.0",
         "ts-jest": "^29.2.5",
         "typescript": "^5.7.2"
@@ -3679,6 +3680,16 @@
       "resolved": "https://registry.npmjs.org/@types/range-parser/-/range-parser-1.2.7.tgz",
       "integrity": "sha512-hKormJbkJqzQGhziax5PItDUTMAM9uE2XXQmM37dyd4hVM+5aVl7oVxMVUiVQn2oCQFN/LKCZdvSM0pFRqbSmQ=="
     },
+    "node_modules/@types/redis": {
+      "version": "4.0.11",
+      "resolved": "https://registry.npmjs.org/@types/redis/-/redis-4.0.11.tgz",
+      "integrity": "sha512-bI+gth8La8Wg/QCR1+V1fhrL9+LZUSWfcqpOj2Kc80ZQ4ffbdL173vQd5wovmoV9i071FU9oP2g6etLuEwb6Rg==",
+      "deprecated": "This is a stub types definition. redis provides its own type definitions, so you do not need this installed.",
+      "dev": true,
+      "dependencies": {
+        "redis": "*"
+      }
+    },
     "node_modules/@types/send": {
       "version": "0.17.4",
       "resolved": "https://registry.npmjs.org/@types/send/-/send-0.17.4.tgz",

package.json

@@ -9,7 +9,7 @@
     "start:dev": "npm run build:dev && node ./dist/index.js",
     "start": "npm run build && node ./dist/index.js",
     "generate": "graphql-codegen --config codegen.ts",
-    "test": "npm run build:dev && jest"
+    "test": "npm run build:dev && jest --runInBand"
   },
   "devDependencies": {
     "@graphql-codegen/cli": "5.0.3",
@@ -18,6 +18,7 @@
     "@jest/globals": "^29.7.0",
     "@types/jsonwebtoken": "^9.0.8",
     "@types/node": "^22.10.2",
+    "@types/redis": "^4.0.11",
     "jest": "^29.7.0",
     "ts-jest": "^29.2.5",
     "typescript": "^5.7.2"

src/index.ts

@@ -10,6 +10,7 @@ import { loadShuttleTestData } from "./loaders/loadShuttleTestData";
 import { AppleNotificationSender } from "./notifications/senders/AppleNotificationSender";
 import { InMemoryNotificationRepository } from "./repositories/InMemoryNotificationRepository";
 import { NotificationRepository } from "./repositories/NotificationRepository";
+import { RedisNotificationRepository } from "./repositories/RedisNotificationRepository";
 
 const typeDefs = readFileSync("./schema.graphqls", "utf8");
 
@@ -24,6 +25,7 @@ async function main() {
 
   let notificationRepository: NotificationRepository;
   let notificationService: ETANotificationScheduler;
+
   if (process.argv.length > 2 && process.argv[2] == "integration-testing") {
     console.log("Using integration testing setup")
     await loadShuttleTestData(shuttleRepository);
@@ -43,7 +45,10 @@ async function main() {
     );
     await repositoryDataUpdater.start();
 
-    notificationRepository = new InMemoryNotificationRepository();
+    const redisNotificationRepository = new RedisNotificationRepository();
+    await redisNotificationRepository.connect();
+
+    notificationRepository = redisNotificationRepository;
     notificationService = new ETANotificationScheduler(
       shuttleRepository,
       notificationRepository

src/repositories/RedisNotificationRepository.ts

@@ -0,0 +1,143 @@
+import { TupleKey } from '../types/TupleKey';
+import {
+  Listener,
+  NotificationEvent,
+  NotificationLookupArguments,
+  NotificationRepository,
+  ScheduledNotification
+} from "./NotificationRepository";
+import { createClient } from "redis";
+
+export class RedisNotificationRepository implements NotificationRepository {
+  private listeners: Listener[] = [];
+  private readonly NOTIFICATION_KEY_PREFIX = 'notification:';
+
+  constructor(
+    private redisClient = createClient({
+      url: process.env.REDIS_URL,
+    }),
+  ) {
+    this.getAllNotificationsForShuttleAndStopId = this.getAllNotificationsForShuttleAndStopId.bind(this);
+    this.getSecondsThresholdForNotificationIfExists = this.getSecondsThresholdForNotificationIfExists.bind(this);
+    this.deleteNotificationIfExists = this.deleteNotificationIfExists.bind(this);
+    this.addOrUpdateNotification = this.addOrUpdateNotification.bind(this);
+    this.isNotificationScheduled = this.isNotificationScheduled.bind(this);
+    this.subscribeToNotificationChanges = this.subscribeToNotificationChanges.bind(this);
+    this.unsubscribeFromNotificationChanges = this.unsubscribeFromNotificationChanges.bind(this);
+  }
+
+  get isReady() {
+    return this.redisClient.isReady;
+  }
+
+  public async connect() {
+    await this.redisClient.connect();
+  }
+
+  public async disconnect() {
+    await this.redisClient.disconnect();
+  }
+
+  public async clearAllData() {
+    await this.redisClient.flushAll();
+  }
+
+  private getNotificationKey(shuttleId: string, stopId: string): string {
+    const tuple = new TupleKey(shuttleId, stopId);
+    return `${this.NOTIFICATION_KEY_PREFIX}${tuple.toString()}`;
+  }
+
+  public async addOrUpdateNotification(notification: ScheduledNotification): Promise<void> {
+    const { shuttleId, stopId, deviceId, secondsThreshold } = notification;
+    const key = this.getNotificationKey(shuttleId, stopId);
+
+    await this.redisClient.hSet(key, deviceId, secondsThreshold.toString());
+
+    this.listeners.forEach((listener: Listener) => {
+      const event: NotificationEvent = {
+        event: 'addOrUpdate',
+        notification
+      };
+      listener(event);
+    });
+  }
+
+  public async deleteNotificationIfExists(lookupArguments: NotificationLookupArguments): Promise<void> {
+    const { shuttleId, stopId, deviceId } = lookupArguments;
+    const key = this.getNotificationKey(shuttleId, stopId);
+
+    const secondsThreshold = await this.redisClient.hGet(key, deviceId);
+    if (secondsThreshold) {
+      await this.redisClient.hDel(key, deviceId);
+
+      // Check if hash is empty and delete it if so
+      const remainingFields = await this.redisClient.hLen(key);
+      if (remainingFields === 0) {
+        await this.redisClient.del(key);
+      }
+
+      this.listeners.forEach((listener) => {
+        const event: NotificationEvent = {
+          event: 'delete',
+          notification: {
+            deviceId,
+            shuttleId,
+            stopId,
+            secondsThreshold: parseInt(secondsThreshold)
+          }
+        };
+        listener(event);
+      });
+    }
+  }
+
+  public async getAllNotificationsForShuttleAndStopId(
+    shuttleId: string,
+    stopId: string
+  ): Promise<ScheduledNotification[]> {
+    const key = this.getNotificationKey(shuttleId, stopId);
+    const allNotifications = await this.redisClient.hGetAll(key);
+
+    return Object.entries(allNotifications).map(([deviceId, secondsThreshold]) => ({
+      shuttleId,
+      stopId,
+      deviceId,
+      secondsThreshold: parseInt(secondsThreshold)
+    }));
+  }
+
+  public async getSecondsThresholdForNotificationIfExists(
+    lookupArguments: NotificationLookupArguments
+  ): Promise<number | null> {
+    const { shuttleId, stopId, deviceId } = lookupArguments;
+    const key = this.getNotificationKey(shuttleId, stopId);
+
+    const threshold = await this.redisClient.hGet(key, deviceId);
+    return threshold ? parseInt(threshold) : null;
+  }
+
+  public async isNotificationScheduled(
+    lookupArguments: NotificationLookupArguments
+  ): Promise<boolean> {
+    const threshold = await this.getSecondsThresholdForNotificationIfExists(lookupArguments);
+    return threshold !== null;
+  }
+
+  public subscribeToNotificationChanges(listener: Listener): void {
+    const index = this.listeners.findIndex(
+      (existingListener) => existingListener === listener
+    );
+    if (index < 0) {
+      this.listeners.push(listener);
+    }
+  }
+
+  public unsubscribeFromNotificationChanges(listener: Listener): void {
+    const index = this.listeners.findIndex(
+      (existingListener) => existingListener === listener
+    );
+    if (index >= 0) {
+      this.listeners.splice(index, 1);
+    }
+  }
+}

test/repositories/NotificationRepositorySharedTests.test.ts

@@ -1,12 +1,53 @@
-import { beforeEach, describe, expect, it, jest } from "@jest/globals";
+import { afterEach, beforeEach, describe, expect, it, jest } from "@jest/globals";
 import { InMemoryNotificationRepository } from "../../src/repositories/InMemoryNotificationRepository";
-import { NotificationEvent } from "../../src/repositories/NotificationRepository";
+import { NotificationEvent, NotificationRepository } from "../../src/repositories/NotificationRepository";
+import { RedisNotificationRepository } from "../../src/repositories/RedisNotificationRepository";
 
-describe("InMemoryNotificationRepository", () => {
+interface RepositoryHolder {
-  let repo: InMemoryNotificationRepository;
+  name: string;
+  factory(): Promise<NotificationRepository>,
+  teardown(): Promise<void>,
+}
 
-  beforeEach(() => {
+class InMemoryRepositoryHolder implements RepositoryHolder {
-    repo = new InMemoryNotificationRepository();
+  name = 'InMemoryNotificationRepository';
+  factory = async () => {
+    return new InMemoryNotificationRepository();
+  }
+  teardown = async () => {}
+}
+
+class RedisNotificationRepositoryHolder implements RepositoryHolder {
+  repo: RedisNotificationRepository | undefined;
+
+  name = 'RedisNotificationRepository';
+  factory = async () => {
+    this.repo = new RedisNotificationRepository();
+    await this.repo.connect();
+    return this.repo;
+  }
+  teardown = async () => {
+    if (this.repo) {
+      await this.repo.clearAllData();
+      await this.repo.disconnect();
+    }
+  }
+}
+
+const repositoryImplementations = [
+  new InMemoryRepositoryHolder(),
+  new RedisNotificationRepositoryHolder(),
+]
+
+describe.each(repositoryImplementations)('$name', (holder) => {
+  let repo: NotificationRepository;
+
+  beforeEach(async () => {
+    repo = await holder.factory();
+  });
+
+  afterEach(async () => {
+    await holder.teardown();
   })
 
   const notification = {
@@ -140,5 +181,33 @@ describe("InMemoryNotificationRepository", () => {
       };
       expect(mockCallback).toHaveBeenCalledWith(expectedEvent);
     });
-  })
+  });
+
+  describe("unsubscribeFromNotificationChanges", () => {
+    it("stops calling subscribers when unsubscribed", async () => {
+      const mockCallback = jest.fn();
+      repo.subscribeToNotificationChanges(mockCallback);
+
+      await repo.addOrUpdateNotification(notification);
+
+      repo.unsubscribeFromNotificationChanges(mockCallback);
+
+      await repo.deleteNotificationIfExists(notification);
+
+      expect(mockCallback).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  describe("isNotificationScheduled", () => {
+    it("returns true if the notification is in the repo", async () => {
+      await repo.addOrUpdateNotification(notification);
+      const result = await repo.isNotificationScheduled(notification);
+      expect(result).toBe(true);
+    });
+
+    it("returns false if the notification isn't in the repo", async () => {
+      const result = await repo.isNotificationScheduled(notification);
+      expect(result).toBe(false);
+    })
+  });
 });