Merge pull request #9 from brendan-ch/chore/test-api-based-repository-loader

chore/test-api-based-repository-loader

.idea/inspectionProfiles/Project_Default.xml

@@ -0,0 +1,6 @@
+<component name="InspectionProjectProfileManager">
+  <profile version="1.0">
+    <option name="myName" value="Project Default" />
+    <inspection_tool class="ExceptionCaughtLocallyJS" enabled="false" level="WARNING" enabled_by_default="false" />
+  </profile>
+</component>

src/loaders/ApiBasedRepositoryLoader.ts

@@ -1,26 +1,39 @@
 import { GetterSetterRepository } from "../repositories/GetterSetterRepository";
 import { IEta, IRoute, IShuttle, IStop, ISystem } from "../entities/entities";
 
-const systemIdsToSupport = ["263"];
-const baseUrl = "https://passiogo.com/mapGetData.php";
+export class ApiResponseError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = "ApiResponseError";
+  }
+}
 
 export class ApiBasedRepositoryLoader {
+  supportedSystemIds = ["263"];
+  baseUrl = "https://passiogo.com/mapGetData.php";
+
   constructor(
-    protected repository: GetterSetterRepository,
+    public repository: GetterSetterRepository,
   ) {
   }
 
-  protected async fetchAndUpdateSystemData() {
+  public async fetchAndUpdateSystemData() {
     const params = {
       getSystems: "2",
     };
     const query = new URLSearchParams(params).toString();
-    const response = await fetch(`${baseUrl}?${query}`);
-    const json = await response.json()
+
+    try {
+      const response = await fetch(`${this.baseUrl}?${query}`);
+      const json = await response.json();
+
+      if (!response.ok) {
+        throw new Error(`HTTP error with status ${response.status}`)
+      }
 
       if (typeof json.all === "object") {
         // filter down to supported systems
-      const filteredSystems = json.all.filter((jsonSystem: any) => systemIdsToSupport.includes(jsonSystem.id));
+        const filteredSystems = json.all.filter((jsonSystem: any) => this.supportedSystemIds.includes(jsonSystem.id));
         await Promise.all(filteredSystems.map(async (system: any) => {
           const constructedSystem: ISystem = {
             id: system.id,
@@ -29,25 +42,37 @@ export class ApiBasedRepositoryLoader {
 
           await this.repository.addOrUpdateSystem(constructedSystem);
         }));
+      } else {
+        throw new Error("Received JSON object does not contain `all` field")
+      }
+    } catch(e: any) {
+      throw new ApiResponseError(e.message);
     }
   }
 
-  protected async fetchAndUpdateRouteDataForExistingSystems() {
+  public async fetchAndUpdateRouteDataForExistingSystemsInRepository() {
     const systems = await this.repository.getSystems();
     await Promise.all(systems.map(async (system) => {
+      await this.fetchAndUpdateRouteDataForSystemId(system.id);
+    }));
+  }
+
+  public async fetchAndUpdateRouteDataForSystemId(systemId: string) {
     const params = {
       getRoutes: "2",
     };
 
     const formDataJsonObject = {
-        "systemSelected0": system.id,
+      "systemSelected0": systemId,
       "amount": "1",
     }
     const formData = new FormData();
     formData.set("json", JSON.stringify(formDataJsonObject));
 
     const query = new URLSearchParams(params).toString();
-      const response = await fetch(`${baseUrl}?${query}`, {
+
+    try {
+      const response = await fetch(`${this.baseUrl}?${query}`, {
         method: "POST",
         body: formData,
       });
@@ -60,53 +85,70 @@ export class ApiBasedRepositoryLoader {
             color: jsonRoute.color,
             id: jsonRoute.myid,
             polylineCoordinates: [],
-            systemId: system.id,
+            systemId: systemId,
           };
 
           await this.repository.addOrUpdateRoute(constructedRoute);
         }))
       }
+    } catch(e: any) {
+      throw new ApiResponseError(e.message);
+    }
+  }
+
+  public async fetchAndUpdateStopAndPolylineDataForRoutesInExistingSystemsInRepository() {
+    const systems = await this.repository.getSystems();
+    await Promise.all(systems.map(async (system: ISystem) => {
+      await this.fetchAndUpdateStopAndPolylineDataForRoutesWithSystemId(system.id);
     }));
   }
 
-  protected async fetchAndUpdateStopAndPolylineDataForRoutesInExistingSystems() {
+  public async fetchAndUpdateStopAndPolylineDataForRoutesWithSystemId(systemId: string) {
     // Fetch from the API
     // Pass JSON output into two different methods to update repository
-    const systems = await this.repository.getSystems();
-    await Promise.all(systems.map(async (system: ISystem) => {
     const params = {
       getStops: "2",
     };
 
     const formDataJsonObject = {
-        "s0": system.id,
+      "s0": systemId,
       "sA": 1
     };
     const formData = new FormData();
     formData.set("json", JSON.stringify(formDataJsonObject));
 
     const query = new URLSearchParams(params).toString();
-      const response = await fetch(`${baseUrl}?${query}`, {
+
+    try {
+      const response = await fetch(`${this.baseUrl}?${query}`, {
         method: "POST",
         body: formData,
       });
       const json = await response.json();
 
-      await this.updateStopDataForSystemAndApiResponse(system, json);
+      await this.updateStopDataForSystemAndApiResponse(systemId, json);
       await this.updateOrderedStopDataForExistingStops(json);
       await this.updatePolylineDataForExistingRoutesAndApiResponse(json);
+    } catch(e: any) {
+      throw new ApiResponseError(e.message);
+    }
+  }
+
+  public async fetchAndUpdateShuttleDataForExistingSystemsInRepository() {
+    const systems = await this.repository.getSystems();
+    await Promise.all(systems.map(async (system: ISystem) => {
+      const systemId = system.id;
+      await this.fetchAndUpdateShuttleDataForSystemId(systemId);
     }));
   }
 
-  protected async fetchAndUpdateShuttleDataForExistingSystems() {
-    const systems = await this.repository.getSystems();
-    await Promise.all(systems.map(async (system: ISystem) => {
+  public async fetchAndUpdateShuttleDataForSystemId(systemId: string) {
     const params = {
       getBuses: "2"
     };
 
     const formDataJsonObject = {
-        "s0": system.id,
+      "s0": systemId,
       "sA": "1"
     };
 
@@ -114,7 +156,9 @@ export class ApiBasedRepositoryLoader {
     formData.set("json", JSON.stringify(formDataJsonObject));
 
     const query = new URLSearchParams(params).toString();
-      const response = await fetch(`${baseUrl}?${query}`, {
+
+    try {
+      const response = await fetch(`${this.baseUrl}?${query}`, {
         method: "POST",
         body: formData,
       });
@@ -133,55 +177,70 @@ export class ApiBasedRepositoryLoader {
               longitude: parseFloat(jsonBus.longitude),
             },
             routeId: jsonBus.routeId,
-            systemId: system.id,
+            systemId: systemId,
             id: `${jsonBus.busId}`
           }
 
           await this.repository.addOrUpdateShuttle(constructedShuttle);
+        }));
+      }
+    } catch(e: any) {
+      throw new ApiResponseError(e.message);
+    }
+  }
+
+  public async fetchAndUpdateEtaDataForExistingStopsForSystemsInRepository() {
+    const systems = await this.repository.getSystems()
+    await Promise.all(systems.map(async (system: ISystem) => {
+      const systemId = system.id;
+      await this.fetchAndUpdateEtaDataForExistingStopsForSystemId(systemId);
     }))
   }
+
+  public async fetchAndUpdateEtaDataForExistingStopsForSystemId(systemId: string) {
+    const stops = await this.repository.getStopsBySystemId(systemId);
+    await Promise.all(stops.map(async (stop) => {
+      let stopId = stop.id;
+      await this.fetchAndUpdateEtaDataForStopId(stopId);
     }));
   }
 
-  protected async fetchAndUpdateEtaDataForExistingOrderedStops() {
-    // TODO implement once I figure out how to associate ETA data with shuttles
-
-    const systems = await this.repository.getSystems()
-    await Promise.all(systems.map(async (system: ISystem) => {
-      const stops = await this.repository.getStopsBySystemId(system.id);
-      await Promise.all(stops.map(async (stop) => {
+  public async fetchAndUpdateEtaDataForStopId(stopId: string) {
     const params = {
       eta: "3",
-          stopIds: stop.id,
+      stopIds: stopId,
     };
 
     const query = new URLSearchParams(params).toString();
-        const response = await fetch(`${baseUrl}?${query}`, {
+
+    try {
+      const response = await fetch(`${this.baseUrl}?${query}`, {
         method: "GET",
       });
       const json = await response.json();
 
-        if (json.ETAs && json.ETAs[stop.id]) {
+      if (json.ETAs && json.ETAs[stopId]) {
         // Continue with the parsing
-          json.ETAs[stop.id].forEach((jsonEta: any) => {
+        json.ETAs[stopId].forEach((jsonEta: any) => {
           // Update cache
           const shuttleId: string = jsonEta.busId;
 
           const eta: IEta = {
             secondsRemaining: jsonEta.secondsSpent,
             shuttleId: `${shuttleId}`,
-              stopId: stop.id,
+            stopId: stopId,
             millisecondsSinceEpoch: Date.now(),
           };
 
           this.repository.addOrUpdateEta(eta);
         });
       }
-      }));
-    }))
+    } catch(e: any) {
+      throw new ApiResponseError(e.message);
+    }
   }
 
-  protected async updateStopDataForSystemAndApiResponse(system: ISystem, json: any) {
+  protected async updateStopDataForSystemAndApiResponse(systemId: string, json: any) {
     if (json.stops) {
       const jsonStops = Object.values(json.stops);
 
@@ -189,7 +248,7 @@ export class ApiBasedRepositoryLoader {
         const constructedStop: IStop = {
           name: stop.name,
           id: stop.id,
-          systemId: system.id,
+          systemId,
           coordinates: {
             latitude: parseFloat(stop.latitude),
             longitude: parseFloat(stop.longitude),

src/loaders/TimedApiBasedRepositoryLoader.ts

@@ -50,13 +50,13 @@ export class TimedApiBasedRepositoryLoader extends ApiBasedRepositoryLoader {
       await this.repository.clearSystemData();
       await this.fetchAndUpdateSystemData();
       await this.repository.clearRouteData();
-      await this.fetchAndUpdateRouteDataForExistingSystems();
+      await this.fetchAndUpdateRouteDataForExistingSystemsInRepository();
       await this.repository.clearStopData();
-      await this.fetchAndUpdateStopAndPolylineDataForRoutesInExistingSystems();
+      await this.fetchAndUpdateStopAndPolylineDataForRoutesInExistingSystemsInRepository();
       await this.repository.clearShuttleData();
-      await this.fetchAndUpdateShuttleDataForExistingSystems();
+      await this.fetchAndUpdateShuttleDataForExistingSystemsInRepository();
       await this.repository.clearEtaData();
-      await this.fetchAndUpdateEtaDataForExistingOrderedStops();
+      await this.fetchAndUpdateEtaDataForExistingStopsForSystemsInRepository();
     } catch (e) {
       console.error(e);
     }

test/jsonSnapshots/fetchEtaData/fetchEtaDataSuccessfulResponse.ts

@@ -1,5 +1,5 @@
 // Snapshot taken from the Passio GO! API
-export const genericEtaDataByStopId = {
+export const fetchEtaDataSuccessfulResponse = {
   "ETAs": {
     "177666": [
       {

test/jsonSnapshots/fetchRouteData/fetchRouteDataSuccessfulResponse.ts

@@ -0,0 +1,153 @@
+export const fetchRouteDataSuccessfulResponse = {
+  "all": [
+    {
+      "name": "Rinker Route",
+      "shortName": null,
+      "color": "#696969",
+      "userId": "263",
+      "myid": "53970",
+      "mapApp": "1",
+      "archive": "0",
+      "goPrefixRouteName": "1",
+      "goShowSchedule": 0,
+      "outdated": "0",
+      "id": "5902",
+      "distance": 1900,
+      "latitude": "33.656851000",
+      "longitude": "-117.733221000",
+      "timezone": "America/Los_Angeles",
+      "fullname": "Chapman University",
+      "nameOrig": "Rinker Route",
+      "groupId": "6706",
+      "groupColor": "#696969"
+    },
+    {
+      "name": "Red Route",
+      "shortName": null,
+      "color": "#d62728",
+      "userId": "263",
+      "myid": "53966",
+      "mapApp": "1",
+      "archive": "0",
+      "goPrefixRouteName": "1",
+      "goShowSchedule": 0,
+      "outdated": "0",
+      "id": "2032",
+      "distance": 1905,
+      "latitude": "33.793325000",
+      "longitude": "-117.852810000",
+      "timezone": "America/Los_Angeles",
+      "fullname": "Chapman University",
+      "nameOrig": "Red Route",
+      "groupId": "6703",
+      "groupColor": "#d62728"
+    },
+    {
+      "name": "Teal Route",
+      "shortName": null,
+      "color": "#096e90",
+      "userId": "263",
+      "myid": "54191",
+      "mapApp": "1",
+      "archive": "0",
+      "goPrefixRouteName": "1",
+      "goShowSchedule": 0,
+      "outdated": "0",
+      "id": "2032",
+      "distance": 1905,
+      "latitude": "33.793325000",
+      "longitude": "-117.852810000",
+      "timezone": "America/Los_Angeles",
+      "fullname": "Chapman University",
+      "nameOrig": "Teal Route",
+      "groupId": "6705",
+      "groupColor": "#096e90"
+    },
+    {
+      "name": "Gold Route",
+      "shortName": null,
+      "color": "#bd9e39",
+      "userId": "263",
+      "myid": "54256",
+      "mapApp": "1",
+      "archive": "0",
+      "goPrefixRouteName": "1",
+      "goShowSchedule": 0,
+      "outdated": "0",
+      "id": "2032",
+      "distance": 1905,
+      "latitude": "33.793325000",
+      "longitude": "-117.852810000",
+      "timezone": "America/Los_Angeles",
+      "fullname": "Chapman University",
+      "nameOrig": "Gold Route",
+      "groupId": "6707",
+      "groupColor": "#bd9e39"
+    },
+    {
+      "name": "Black Route",
+      "shortName": null,
+      "color": "#000000",
+      "userId": "263",
+      "myid": "54257",
+      "mapApp": "1",
+      "archive": "0",
+      "goPrefixRouteName": "1",
+      "goShowSchedule": 0,
+      "outdated": "0",
+      "id": "2032",
+      "distance": 1905,
+      "latitude": "33.793325000",
+      "longitude": "-117.852810000",
+      "timezone": "America/Los_Angeles",
+      "fullname": "Chapman University",
+      "nameOrig": "Black Route",
+      "groupId": "6704",
+      "groupColor": "#000000"
+    },
+    {
+      "name": "Weekend Route",
+      "shortName": null,
+      "color": "#510094",
+      "userId": "263",
+      "myid": "54282",
+      "mapApp": "1",
+      "archive": "0",
+      "goPrefixRouteName": "1",
+      "goShowSchedule": 0,
+      "outdated": "1",
+      "id": "2032",
+      "distance": 1905,
+      "latitude": "33.793325000",
+      "longitude": "-117.852810000",
+      "timezone": "America/Los_Angeles",
+      "fullname": "Chapman University",
+      "nameOrig": "Weekend Route",
+      "groupId": "6710",
+      "groupColor": "#510094",
+      "serviceTime": "is not provided: no bus on the route",
+      "serviceTimeShort": "No bus in service"
+    },
+    {
+      "name": "Parking Lot",
+      "shortName": null,
+      "color": "#000000",
+      "userId": "263",
+      "myid": "54529",
+      "mapApp": "1",
+      "archive": "0",
+      "goPrefixRouteName": "1",
+      "goShowSchedule": 0,
+      "outdated": "0",
+      "id": "2032",
+      "distance": 1905,
+      "latitude": "33.793325000",
+      "longitude": "-117.852810000",
+      "timezone": "America/Los_Angeles",
+      "fullname": "Chapman University",
+      "nameOrig": "Parking Lot",
+      "groupId": "6731",
+      "groupColor": "#393838"
+    }
+  ]
+}

test/jsonSnapshots/fetchShuttleData/fetchShuttleDataSuccessfulResponse.ts

@@ -1,5 +1,5 @@
 // Snapshot taken from the Passio GO! API
-export const genericShuttleDataBySystemId = {
+export const fetchShuttleDataSuccessfulResponse = {
   "alertCRC": "23c1b91c",
   "buses": {
     "402840": [

test/jsonSnapshots/fetchSystemData/fetchSystemDataFailedResponse.ts

@@ -0,0 +1,5 @@
+// Not an actual response snapshot
+// Simulate a case where `all` property of response is unavailable
+export const fetchSystemDataFailedResponse = {
+  "error": "no systems",
+};

test/loaders/ApiBasedRepositoryLoaderTests.test.ts

@@ -0,0 +1,279 @@
+import { beforeEach, describe, expect, it, jest, test } from "@jest/globals";
+import { ApiBasedRepositoryLoader, ApiResponseError } from "../../src/loaders/ApiBasedRepositoryLoader";
+import { UnoptimizedInMemoryRepository } from "../../src/repositories/UnoptimizedInMemoryRepository";
+import { fetchSystemDataSuccessfulResponse } from "../jsonSnapshots/fetchSystemData/fetchSystemDataSuccessfulResponse";
+import { fetchSystemDataFailedResponse } from "../jsonSnapshots/fetchSystemData/fetchSystemDataFailedResponse";
+import { fetchRouteDataSuccessfulResponse } from "../jsonSnapshots/fetchRouteData/fetchRouteDataSuccessfulResponse";
+import {
+  fetchStopAndPolylineDataSuccessfulResponse
+} from "../jsonSnapshots/fetchStopAndPolylineData/fetchStopAndPolylineDataSuccessfulResponse";
+import { generateMockStops, generateMockSystems } from "../generators";
+import { IStop } from "../../src/entities/entities";
+import {
+  fetchShuttleDataSuccessfulResponse
+} from "../jsonSnapshots/fetchShuttleData/fetchShuttleDataSuccessfulResponse";
+import { fetchEtaDataSuccessfulResponse } from "../jsonSnapshots/fetchEtaData/fetchEtaDataSuccessfulResponse";
+
+/**
+ * Function to update behavior of the global `fetch` function.
+ * Note that the Passio GO API returns status code 200 for failed responses.
+ * @param obj
+ * @param status
+ */
+function updateGlobalFetchMockJson(
+  obj: any,
+  status: number = 200
+) {
+  // @ts-ignore
+  global.fetch = jest.fn(() => {
+    return Promise.resolve({
+      json: () => Promise.resolve(obj),
+      status,
+      ok: status.toString().startsWith("2"), // 200-level codes are OK
+    })
+  }) as jest.Mock;
+}
+
+/**
+ * Reset the global fetch function mock's JSON to return an empty object.
+ * @param obj
+ */
+function resetGlobalFetchMockJson() {
+  updateGlobalFetchMockJson({});
+}
+
+async function assertAsyncCallbackThrowsApiResponseError(callback: () => Promise<any>) {
+  await expect(callback).rejects.toThrow(ApiResponseError);
+}
+
+function updateGlobalFetchMockJsonToThrowSyntaxError() {
+  // @ts-ignore
+  global.fetch = jest.fn(() => {
+    return Promise.resolve({
+      json: () => Promise.reject(new SyntaxError("Unable to parse JSON")),
+      status: 200,
+      ok: true,
+    })
+  }) as jest.Mock;
+}
+
+describe("ApiBasedRepositoryLoader", () => {
+  let loader: ApiBasedRepositoryLoader;
+
+  beforeEach(() => {
+    loader = new ApiBasedRepositoryLoader(new UnoptimizedInMemoryRepository());
+    resetGlobalFetchMockJson();
+  });
+
+  describe("fetchAndUpdateSystemData", () => {
+    it("updates system data in repository if response received", async () => {
+      const numberOfSystemsInResponse = fetchSystemDataSuccessfulResponse.all.length;
+      updateGlobalFetchMockJson(fetchSystemDataSuccessfulResponse);
+
+      await loader.fetchAndUpdateSystemData();
+
+      const systems = await loader.repository.getSystems();
+      if (loader.supportedSystemIds.length < numberOfSystemsInResponse) {
+        expect(systems).toHaveLength(loader.supportedSystemIds.length);
+      } else {
+        expect(systems).toHaveLength(numberOfSystemsInResponse);
+      }
+    });
+
+    it("throws the correct error if the API response contains no data", async () => {
+      updateGlobalFetchMockJson(fetchSystemDataFailedResponse);
+
+      await assertAsyncCallbackThrowsApiResponseError(async () => {
+        await loader.fetchAndUpdateSystemData();
+      });
+    });
+
+    it("throws the correct error if HTTP status code is not 200", async () => {
+      updateGlobalFetchMockJson(fetchSystemDataFailedResponse, 400);
+
+      await assertAsyncCallbackThrowsApiResponseError(async () => {
+        await loader.fetchAndUpdateSystemData();
+      });
+    });
+  });
+
+
+  describe("fetchAndUpdateRouteDataForExistingSystemsInRepository", () => {
+    test("calls fetchAndUpdateRouteDataForSystemId for all systems in repository", async () => {
+      const spy = jest.spyOn(loader, "fetchAndUpdateRouteDataForSystemId");
+
+      const systems = generateMockSystems();
+
+      await Promise.all(systems.map(async (system) => {
+        await loader.repository.addOrUpdateSystem(system);
+      }));
+
+      await loader.fetchAndUpdateRouteDataForExistingSystemsInRepository();
+
+      expect(spy.mock.calls.length).toBe(systems.length);
+    });
+  });
+
+  describe("fetchAndUpdateRouteDataForSystemId", () => {
+    it("updates route data in repository if response received", async () => {
+      updateGlobalFetchMockJson(fetchRouteDataSuccessfulResponse);
+
+      await loader.fetchAndUpdateRouteDataForSystemId("263");
+
+      const routes = await loader.repository.getRoutesBySystemId("263");
+
+      expect(routes.length).toEqual(fetchRouteDataSuccessfulResponse.all.length)
+    });
+
+    it("throws the correct error if the API response contains no data", async () => {
+      // The Passio API returns some invalid JSON if there is no data,
+      // so simulate a JSON parsing error
+
+      updateGlobalFetchMockJsonToThrowSyntaxError();
+
+      await assertAsyncCallbackThrowsApiResponseError(async () => {
+        await loader.fetchAndUpdateRouteDataForSystemId("263");
+      });
+    });
+  });
+
+  describe("fetchAndUpdateStopAndPolylineDataForRoutesInExistingSystemsInRepository", () => {
+    it("calls fetchAndUpdateStopAndPolylineDataForRoutesWithSystemId for every system", async () => {
+      const spy = jest.spyOn(loader, "fetchAndUpdateStopAndPolylineDataForRoutesWithSystemId");
+
+      const systems = generateMockSystems();
+
+      await Promise.all(systems.map(async (system) => {
+        await loader.repository.addOrUpdateSystem(system);
+      }));
+
+      await loader.fetchAndUpdateStopAndPolylineDataForRoutesInExistingSystemsInRepository();
+
+      expect(spy.mock.calls.length).toBe(systems.length);
+    });
+  })
+
+  describe("fetchAndUpdateStopAndPolylineDataForRoutesWithSystemId", () => {
+    it("updates stop and polyline data if response received", async () => {
+      updateGlobalFetchMockJson(fetchStopAndPolylineDataSuccessfulResponse);
+
+      const stopsArray = Object.values(fetchStopAndPolylineDataSuccessfulResponse.stops);
+
+      await loader.fetchAndUpdateStopAndPolylineDataForRoutesWithSystemId("263");
+
+      const stops = await loader.repository.getStopsBySystemId("263");
+      expect(stops.length).toEqual(stopsArray.length);
+
+      await Promise.all(stops.map(async (stop) => {
+        const orderedStops = await loader.repository.getOrderedStopsByStopId(stop.id)
+        expect(orderedStops.length).toBeGreaterThan(0);
+      }));
+
+      const routes = await loader.repository.getRoutesBySystemId("263");
+      routes.forEach((route) => {
+        expect(route.polylineCoordinates.length).toBeGreaterThan(0);
+      });
+    });
+
+    it("throws the correct error if the API response contains no data", async () => {
+      updateGlobalFetchMockJsonToThrowSyntaxError();
+
+      await assertAsyncCallbackThrowsApiResponseError(async () => {
+        await loader.fetchAndUpdateStopAndPolylineDataForRoutesWithSystemId("263");
+      });
+    })
+  });
+
+  describe("fetchAndUpdateShuttleDataForExistingSystemsInRepository", () => {
+    it("calls fetchAndUpdateShuttleDataForSystemId for every system", async () => {
+      const spy = jest.spyOn(loader, "fetchAndUpdateShuttleDataForSystemId");
+
+      const systems = generateMockSystems();
+      await Promise.all(systems.map(async (system) => {
+        await loader.repository.addOrUpdateSystem(system);
+      }))
+
+      await loader.fetchAndUpdateShuttleDataForExistingSystemsInRepository();
+
+      expect(spy.mock.calls.length).toBe(systems.length);
+    });
+  });
+
+  describe("fetchAndUpdateShuttleDataForSystemId", () => {
+    it("updates shuttle data in repository if response received", async () => {
+      updateGlobalFetchMockJson(fetchShuttleDataSuccessfulResponse);
+      const busesInResponse = Object.values(fetchShuttleDataSuccessfulResponse.buses);
+
+      await loader.fetchAndUpdateShuttleDataForSystemId("263");
+
+      const shuttles = await loader.repository.getShuttlesBySystemId("263");
+
+      expect(shuttles.length).toEqual(busesInResponse.length);
+    });
+
+    it("throws the correct error if the API response contains no data", async () => {
+      updateGlobalFetchMockJsonToThrowSyntaxError();
+
+      await assertAsyncCallbackThrowsApiResponseError(async () => {
+        await loader.fetchAndUpdateShuttleDataForSystemId("263");
+      });
+    });
+  });
+
+  describe("fetchAndUpdateEtaDataForExistingStopsForSystemsInRepository", () => {
+    it("calls fetchAndUpdateEtaDataFoExistingStopsForSystemId for every system in repository", async () => {
+      const spy = jest.spyOn(loader, "fetchAndUpdateEtaDataForExistingStopsForSystemId");
+
+      const systems = generateMockSystems();
+      await Promise.all(systems.map(async (system) => {
+        await loader.repository.addOrUpdateSystem(system);
+      }));
+
+      await loader.fetchAndUpdateEtaDataForExistingStopsForSystemsInRepository();
+
+      expect(spy.mock.calls.length).toBe(systems.length);
+    });
+  });
+
+  describe("fetchAndUpdateEtaDataForExistingStopsForSystemId", () => {
+    it("calls fetchAndUpdateEtaDataForStopId for every stop in repository", async () => {
+      const spy = jest.spyOn(loader, "fetchAndUpdateEtaDataForStopId");
+
+      const stops = generateMockStops();
+      stops.forEach((stop) => {
+        stop.systemId = "1";
+      });
+
+      await Promise.all(stops.map(async (stop) => {
+        await loader.repository.addOrUpdateStop(stop);
+      }));
+
+      await loader.fetchAndUpdateEtaDataForExistingStopsForSystemId("1");
+
+      expect(spy.mock.calls.length).toEqual(stops.length);
+    });
+  });
+
+  describe("fetchAndUpdateEtaDataForStopId", () => {
+    it("updates ETA data for stop id if response received", async () => {
+      updateGlobalFetchMockJson(fetchEtaDataSuccessfulResponse);
+      const stopId = "177666";
+      // @ts-ignore
+      const etasFromResponse = fetchEtaDataSuccessfulResponse.ETAs[stopId]
+
+      await loader.fetchAndUpdateEtaDataForStopId(stopId);
+
+      const etas = await loader.repository.getEtasForStopId(stopId);
+      expect(etas.length).toEqual(etasFromResponse.length);
+    });
+
+    it("throws the correct error if the API response contains no data", async () => {
+      updateGlobalFetchMockJsonToThrowSyntaxError();
+
+      await assertAsyncCallbackThrowsApiResponseError(async () => {
+        await loader.fetchAndUpdateEtaDataForStopId("263");
+      });
+    });
+  });
+});
+