[Updated] Reflection

README.md

@@ -35,4 +35,15 @@ sudo reboot
 ```bash
 docker compose up
 ```
-- Visit localhost:4200 to play the quiz!
+- Visit localhost:4200 to play the quiz!
+
+
+## Benchmarking
+- Go to the /scripts folder and run the LoadTestMultiple.sh script
+- Inside you can change how many sessions should be created (set to 6 by default)
+- In the /scripts/benchmarks folder you can find some benchmarks I've done
+
+## Notes
+- If the data is not present, it will try to query it from the external API, which takes significantly longer (only 1 request per 5 seconds)
+- When running it locally, give the backend a few minutes to gather data in bulk (should be completely done in ~7 minutes)
+- It refreshes this data every night in the background, so it stays up to date

Reflection.md

@@ -1,20 +1,20 @@
-# Issues
+# Reflection
 
-## Issues during testing
+## Issues during testing (October 30th)
 ### Scheduler
 I don't know if it was the scheduler specifically, but whenever I try to test it, both the cache and the queue seem to become empty after the first function is completed.
 I don't know how to solve this yet
 
 
-## Caching solution
+## Caching solution (October 30th)
 ### Lack of data
-Not being able to gather blocks of 50 is a huge issue. The idea of reusing blocks becomes less viable if I can just get a big chunk every time for others to use
+Not being able to gather blocks of 50 is a big issue. The idea of reusing blocks becomes less viable if I can't just get a big chunk every time for others to use.
 I can't force a big chunk, because it might just return a status 1, and then the user gets nothing.
 
 Perhaps I can separate the questions myself and make a collection, that i can build the requests from. However, for every quest tracking if someone has already seen is a huge pain.
 
 
-## Possible solution
+## Possible solution (October 31st)
 Cache all data, 50 at a time
 Store it in a database
 When its done, let the db make blocks for quick cache access
@@ -28,3 +28,36 @@ Then start replacing the cache items one at a time.
 
 Users shouldn't feel this at all, because the active sessions are stored in their own cache items
 
+# Progress so far (November 3rd)
+There only seem to be ~4100 items, making the collecting phase only last around 7 minutes.
+
+Swapping dbs is replaced with swapping tables, seems to work just as fine, yet much simpler to set up
+
+TODO: Add a caching state, and start filling up each unique combination with the items from the db
+This should lead to performance gains
+
+## Possible future alternative
+In the current state (when the cache is done), the backend might hold data 3 times (Cache, active DB table, and background DB table during the night)
+
+### Purely Cached solution
+- Every night
+- Check for each category+difficulty combination how many questions there are (API has an endpoint for this)
+- Track which one you are on, and how many you have
+- Take blocks of 50, until the remaining items are less than 50, then get that exact amount
+- When they are gathered, either 
+    1. Divide them between 3 cache items: cat:dif:any/multiple/boolean 
+    - (Manually filter on the type, since the API sends questions with either option together), or 
+    2. In one like cat:dif:any and then filter it by hand when a user asks for it
+    - (This will replace the collection put there the night before)
+- Then move to the next one
+- Stop when the last combination has been collected
+
+#### When a user requests data: 
+- Get the items from the cache
+- Less items than requested: Inform the user to try a different combination
+- More items than requested: Randomize and select a subset
+
+### Tradeoffs
+- Advantage: Less total data held on the server
+
+- Downside: Slower gathering, since there are 25+3+4=300 unique combinations (each of which will end with a request of less than 50 items), it will require a decent number requests more than the bulk collecting that the DB does.

backend/src/main/java/com/ninjaws/quiz/controllers/QuizController.java

@@ -1,5 +1,6 @@
 package com.ninjaws.quiz.controllers;
 
+import java.util.List;
 import java.util.Optional;
 
 import org.springframework.beans.factory.annotation.Autowired;
@@ -11,9 +12,11 @@ import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
 
+import com.ninjaws.quiz.entities.Category;
 import com.ninjaws.quiz.models.Answers;
 import com.ninjaws.quiz.models.QuizSettings;
 import com.ninjaws.quiz.models.Session;
+import com.ninjaws.quiz.services.DataService;
 import com.ninjaws.quiz.services.QuizService;
 
 @RestController
@@ -22,6 +25,8 @@ public class QuizController {
 
     @Autowired
     private QuizService quizService;
+    @Autowired
+    private DataService dataService;
 
 
     /**
@@ -69,4 +74,9 @@ public class QuizController {
         String jsonString = String.format("{\"score\":\"%s\"}", quizService.getScore(answers));
         return jsonString;
     }
+
+    @GetMapping("/categories")
+    public List<Category> getCategories(){
+        return dataService.getCategories();
+    }
 }

backend/src/main/java/com/ninjaws/quiz/services/DataService.java

@@ -50,6 +50,9 @@ public class DataService {
         return categoryRepository.saveAll(categories);
     }
 
+    public List<Category> getCategories(){
+        return categoryRepository.findAll();
+    }
     /**
      * Moving the collected questions to the questions list
      *

backend/src/main/java/com/ninjaws/quiz/services/QuizService.java

@@ -24,6 +24,8 @@ public class QuizService {
     private DataService dataService;
     @Autowired
     private CleanerService cleanerService;
+    @Autowired
+    private StateManagementService stateManager;
 
     /**
      * Actions:
@@ -38,19 +40,20 @@ public class QuizService {
 
         /** First, we check if there are already enough items in our db */
         List<QuestionEntity> questionsRetrieved = dataService.lookupQuestions(quizSettings);
+        /** If the items are not matching the required amount, and the db is not currently being filled up, then they simply don't exist */
+        if (questionsRetrieved.size() < quizSettings.getAmount() && stateManager.getCurrentProcessingState() != StateManagementService.ProcessingState.STARTUP) {
+            session.setStatusCode(1);
+            cacheService.addToCache(session.getId(), session);
+            return Optional.of(session.getId());
+        }
+        /** All items are collected in from the database, it doesn't need to be added to the queue */
         if(!questionsRetrieved.isEmpty() && questionsRetrieved.size() == quizSettings.getAmount()) {
             session.setQuestions(cleanerService.questionListEntitytoDTO(questionsRetrieved));
-        }
-
-        cacheService.addToCache(session.getId(), session);
-
-        /**
-         * If the questions were retrieved from the DB, then it doesn't need to be added to the queue
-         */
-        if(!questionsRetrieved.isEmpty() && questionsRetrieved.size() == quizSettings.getAmount()) {
+            cacheService.addToCache(session.getId(), session);
             return Optional.of(session.getId());
         }
 
+        cacheService.addToCache(session.getId(), session);
         boolean addedToQueue = queueService.addToQueue(new Request(session.getId(), quizSettings));
         /** In this order, because doing the queue before the cache could lead to race conditions (request completion immediately calls cache, but then the item doesn't exist) */
         if(!addedToQueue) {
@@ -75,16 +78,17 @@ public class QuizService {
             throw new IllegalArgumentException("Invalid session ID: " + sessionId);
         }
 
+        /** Anything other than statuscode 0 doesn't result in active sessions, so remove them from the cache after reporting to the frontend */
+        if(session.getStatusCode() != 0) {
+            cacheService.removeFromCache(session.getId());
+            return Optional.of(session);
+        }
+
         /** Still waiting for a response */
         if (session.getQuestions() == null) {
             return Optional.empty();
         }
 
-        /** Anything other than statuscode 0 doesn't result in active sessions, so remove them from the cache after reporting to the frontend */
-        // if(session.getStatusCode() != 0) {
-        /** Regardless of status code, this link is not reusable */
-        cacheService.removeFromCache(session.getId());
-        // }
 
         return Optional.of(session);
     }
@@ -93,7 +97,7 @@ public class QuizService {
      * Receives: sessionId and answers
      * 
      * Actions: 
-     * - retrieves session from cache
+     * - Retrieves session from cache
      * - Deletes session from cache
      * - Matches answers answers to correctAnswers
      * - Calculates score

backend/src/test/java/com/ninjaws/quiz/scala/QuestionStatusSimulation.scala

@@ -3,6 +3,7 @@ import io.gatling.core.Predef._
 import io.gatling.http.Predef._
 import scala.concurrent.duration._
 
+/** Does not work, use the LoadTestMultiple.sh in the /scripts folder in the root instead */
 class QuestionStatusSimulation extends Simulation {
     val httpProtocol = http.baseUrl("http://localhost:9090").acceptHeader("application/json")
 

frontend/src/app/Quiz/models/category.ts

@@ -0,0 +1,4 @@
+export interface Category {
+    id: number;
+    name: string;
+}

frontend/src/app/Quiz/models/quiz-params.ts

@@ -1,5 +1,7 @@
+import { Category } from "./category";
+
 export interface QuizParams {
-    category: string;
+    category: number;
     type: string;
     amount: number;
     difficulty: string;

frontend/src/app/Quiz/services/quiz.service.ts

@@ -19,6 +19,7 @@ import { StorageService } from './storage.service';
 import { CleanerService } from './cleaner.service';
 import { ResponseHandlerService } from './response-handler.service';
 import { environment } from '../../../environments/environment';
+import { Category } from '../models/category';
 
 @Injectable({
   providedIn: 'root',
@@ -40,8 +41,7 @@ export class QuizService {
     }
     this.storageService.setSession(sessionIdObj.sessionId);
     const sessionObj = await lastValueFrom(this.pollQuestions(sessionIdObj.sessionId));
-
-    return this.reponseHandler.handleResponse(sessionIdObj.statusCode, sessionObj);
+    return this.reponseHandler.handleResponse(sessionObj.statusCode, sessionObj);
   }
 
   public pollQuestions(sessionId: string) {
@@ -67,7 +67,7 @@ export class QuizService {
 
   private convertParamsToUrl(quizParams: QuizParams) {
     let url = `?amount=${quizParams.amount}`;
-    const catIndex = this.getCategories().indexOf(quizParams.category);
+    const catIndex = quizParams.category;
     url += catIndex !== 0 ? `&category=${catIndex}` : '';
 
     const diff = quizParams.difficulty.toLowerCase();
@@ -83,34 +83,11 @@ export class QuizService {
     return url;
   }
 
-  public getCategories(): string[] {
-    return [
-      'Any Category',
-      'General Knowledge',
-      'Entertainment: Books',
-      'Entertainment: Film',
-      'Entertainment: Music',
-      'Entertainment: Musicals & Theatres',
-      'Entertainment: Television',
-      'Entertainment: Video Games',
-      'Entertainment: Board Games',
-      'Science & Nature',
-      'Science: Computers',
-      'Science: Mathematics',
-      'Mythology',
-      'Sports',
-      'Geography',
-      'History',
-      'Politics',
-      'Art',
-      'Celebrities',
-      'Animals',
-      'Vehicles',
-      'Entertainment: Comics',
-      'Science: Gadgets',
-      'Entertainment: Japanese Anime & Manga',
-      'Entertainment: Cartoon & Animations',
-    ];
+  public async getCategories(): Promise<Category[]> {
+    let categories: Category[] = await firstValueFrom(this.http.get<any>(this.apiUrl + '/categories'));
+    categories.push({id:0,name:"Any Category"});
+    categories.sort((a,b) => a.id - b.id);
+    return categories;
   }
 
   public getDifficulties(): string[] {

frontend/src/app/Quiz/setup/setup.component.html

@@ -5,7 +5,7 @@
         <div class="mb-4">
             <label for="category" class="block mb-1">Category</label>
             <select id="category" class="w-full p-2 border rounded" [(ngModel)]="category">
-                <option *ngFor="let category of quizService.getCategories()" [value]="category">{{ category }}</option>
+                <option *ngFor="let category of categories" [value]="category.id">{{ category.name }}</option>
             </select>
         </div>
 

frontend/src/app/Quiz/setup/setup.component.ts

@@ -7,6 +7,7 @@ import { QuizParams } from '../models/quiz-params';
 import { SpinnerService } from '../../Spinner/services/spinner.service';
 import { CommonModule } from '@angular/common';
 import { Question } from '../models/question';
+import { Category } from '../models/category';
 
 @Component({
   selector: 'app-setup',
@@ -17,8 +18,8 @@ import { Question } from '../models/question';
 })
 export class SetupComponent {
 
-
-  category: string = "";
+  categories!: Category[];
+  category!: number;
   difficulty: string = "";
   type: string = "";
   amount: number = 10;
@@ -28,10 +29,13 @@ export class SetupComponent {
     public quizService: QuizService,
     private spinnerService: SpinnerService
   ) {
-    /** Setting default values */
-    this.category = this.quizService.getCategories()[0];
-    this.difficulty = this.quizService.getDifficulties()[0];
-    this.type = this.quizService.getTypes()[0];
+    quizService.getCategories().then((categories: Category[]) => {
+      /** Setting default values */
+      this.categories = categories;
+      this.category = this.categories.find(item => item.id == 0)!.id;
+      this.difficulty = this.quizService.getDifficulties()[0];
+      this.type = this.quizService.getTypes()[0];      
+    });
   }
 
   startQuiz() {

scripts/LoadTestMultiple.sh

@@ -2,16 +2,15 @@
 
 start_time=$(date +%s)
 
-for i in {1..1000}; do
+for i in {1..6}; do
   ./LoadTestOne-Silent.sh &
 #   sleep 0.1
 done
 
-wait  # Wait for all background jobs to finish
+wait
 
-end_time=$(date +%s)  # Capture the end time
+end_time=$(date +%s)
 
-# Calculate and print the elapsed time
 elapsed_time=$((end_time - start_time))
 echo "Done!"
 echo "Total time taken: $elapsed_time seconds"