Feat/rate limiting user quotas

.prettierrc

@@ -7,7 +7,7 @@
   "useTabs": false,
   "bracketSpacing": true,
   "arrowParens": "always",
-  "endOfLine": "lf",
+  "endOfLine": "auto",
   "quoteProps": "as-needed",
   "overrides": [
     {

src/ab-testing/ab-testing.module.ts

@@ -34,5 +34,4 @@ import { ABTestingController } from './ab-testing.controller';
     ABTestingReportsService,
   ],
 })
-export class ABTestingModule {
-}
+export class ABTestingModule {}

src/ab-testing/analysis/statistical-analysis.service.ts

@@ -245,7 +245,10 @@ export class StatisticalAnalysisService {
     return Math.max(0, Math.min(1, 1 / (1 + Math.exp(-zScore + 2))));
   }
 
-  private calculateCohensD(controlMetrics: VariantMetric[], variantMetrics: VariantMetric[]): number {
+  private calculateCohensD(
+    controlMetrics: VariantMetric[],
+    variantMetrics: VariantMetric[],
+  ): number {
     if (controlMetrics.length === 0 || variantMetrics.length === 0) return 0;
 
     const controlMean =
@@ -257,12 +260,16 @@ export class StatisticalAnalysisService {
     const denomV = Math.max(variantMetrics.length - 1, 1);
 
     const controlVar =
-      controlMetrics.reduce((sum, m) => sum + Math.pow(Number(m.value) - controlMean, 2), 0) / denomC;
+      controlMetrics.reduce((sum, m) => sum + Math.pow(Number(m.value) - controlMean, 2), 0) /
+      denomC;
     const variantVar =
-      variantMetrics.reduce((sum, m) => sum + Math.pow(Number(m.value) - variantMean, 2), 0) / denomV;
+      variantMetrics.reduce((sum, m) => sum + Math.pow(Number(m.value) - variantMean, 2), 0) /
+      denomV;
 
-    const pooledStdDev = Math.sqrt(((controlMetrics.length - 1) * controlVar + (variantMetrics.length - 1) * variantVar) /
-      Math.max(controlMetrics.length + variantMetrics.length - 2, 1));
+    const pooledStdDev = Math.sqrt(
+      ((controlMetrics.length - 1) * controlVar + (variantMetrics.length - 1) * variantVar) /
+        Math.max(controlMetrics.length + variantMetrics.length - 2, 1),
+    );
 
     return pooledStdDev > 0 ? Math.abs(variantMean - controlMean) / pooledStdDev : 0;
   }

src/ab-testing/automation/automated-decision.service.ts

@@ -49,8 +49,7 @@ export class AutomatedDecisionService {
 
     const defaultCriteria: IWinnerSelectionCriteria = {
       confidenceLevel: experiment.confidenceLevel ?? AB_TESTING_CONSTANTS.DEFAULT_CONFIDENCE_LEVEL,
-      minimumSampleSize:
-        experiment.minimumSampleSize ?? AB_TESTING_CONSTANTS.MINIMUM_SAMPLE_SIZE,
+      minimumSampleSize: experiment.minimumSampleSize ?? AB_TESTING_CONSTANTS.MINIMUM_SAMPLE_SIZE,
       effectSizeThreshold: AB_TESTING_CONSTANTS.EFFECT_SIZE_THRESHOLD,
       durationThreshold: AB_TESTING_CONSTANTS.DURATION_THRESHOLD_DAYS,
     };
@@ -263,14 +262,13 @@ export class AutomatedDecisionService {
         });
         if (winner) {
           recommendations.winnerCandidate = winner.id;
-          recommendations.recommendations.push(`Variant "${winner.name}" is the recommended winner`);
+          recommendations.recommendations.push(
+            `Variant "${winner.name}" is the recommended winner`,
+          );
         }
       }
     } else {
-      const remainingDays = Math.max(
-        0,
-        AB_TESTING_CONSTANTS.DURATION_THRESHOLD_DAYS - duration,
-      );
+      const remainingDays = Math.max(0, AB_TESTING_CONSTANTS.DURATION_THRESHOLD_DAYS - duration);
       recommendations.recommendations.push(
         `Wait ${remainingDays} more days before making decision`,
       );
@@ -300,8 +298,7 @@ export class AutomatedDecisionService {
     for (let i = 0; i < variants.length; i++) {
       const variant = variants[i];
       const score = performanceScores[i];
-      variant.trafficAllocation =
-        totalScore > 0 ? score.score / totalScore : 1 / variants.length;
+      variant.trafficAllocation = totalScore > 0 ? score.score / totalScore : 1 / variants.length;
       await this.variantRepository.save(variant);
     }
 

src/ab-testing/entities/experiment-metric.entity.ts

@@ -9,11 +9,11 @@ import {
 } from 'typeorm';
 import { Experiment } from './experiment.entity';
 export enum MetricType {
-    CONVERSION = 'conversion',
-    REVENUE = 'revenue',
-    ENGAGEMENT = 'engagement',
-    RETENTION = 'retention',
-    CUSTOM = 'custom'
+  CONVERSION = 'conversion',
+  REVENUE = 'revenue',
+  ENGAGEMENT = 'engagement',
+  RETENTION = 'retention',
+  CUSTOM = 'custom',
 }
 
 /**

src/ab-testing/entities/experiment.entity.ts

@@ -10,16 +10,16 @@ import {
 import { IExperimentVariant } from './experiment-variant.entity';
 import { ExperimentMetric } from './experiment-metric.entity';
 export enum ExperimentStatus {
-    DRAFT = 'draft',
-    RUNNING = 'running',
-    PAUSED = 'paused',
-    COMPLETED = 'completed',
-    ARCHIVED = 'archived'
+  DRAFT = 'draft',
+  RUNNING = 'running',
+  PAUSED = 'paused',
+  COMPLETED = 'completed',
+  ARCHIVED = 'archived',
 }
 export enum ExperimentType {
-    A_B_TEST = 'a_b_test',
-    MULTIVARIATE = 'multivariate',
-    MULTI_ARMED_BANDIT = 'multi_armed_bandit'
+  A_B_TEST = 'a_b_test',
+  MULTIVARIATE = 'multivariate',
+  MULTI_ARMED_BANDIT = 'multi_armed_bandit',
 }
 
 /**

src/ab-testing/reporting/ab-testing-reports.service.ts

@@ -19,8 +19,8 @@ export interface IReportFilters {
  */
 @Injectable()
 export class ABTestingReportsService {
-    private readonly logger = new Logger(ABTestingReportsService.name);
-    constructor(
+  private readonly logger = new Logger(ABTestingReportsService.name);
+  constructor(
     @InjectRepository(Experiment)
     private experimentRepository: Repository<Experiment>,
     @InjectRepository(IExperimentVariant)
@@ -256,7 +256,9 @@ export class ABTestingReportsService {
           : 0,
       bestPerforming:
         performanceData.length > 0
-          ? [...performanceData].sort((a, b) => b.improvementPercentage - a.improvementPercentage)[0]
+          ? [...performanceData].sort(
+              (a, b) => b.improvementPercentage - a.improvementPercentage,
+            )[0]
           : null,
       performanceData,
     };

src/app.controller.ts

@@ -1,7 +1,9 @@
 import { Controller, Get } from '@nestjs/common';
 import { ApiTags, ApiOperation, ApiResponse } from '@nestjs/swagger';
+import { SkipQuota } from './rate-limiting/decorators/quota.decorator';
 
 @ApiTags('App')
+@SkipQuota()
 @Controller()
 export class AppController {
   @Get()

src/app.module.ts

@@ -1,14 +1,30 @@
 import { Module } from '@nestjs/common';
+import { APP_GUARD } from '@nestjs/core';
+import { ConfigModule } from '@nestjs/config';
+import { TypeOrmModule } from '@nestjs/typeorm';
+import { ScheduleModule } from '@nestjs/schedule';
 import { AppController } from './app.controller';
 import { SearchModule } from './search/search.module';
+import { RateLimitingModule } from './rate-limiting/rate-limiting.module';
+import { QuotaGuard } from './rate-limiting/guards/quota.guard';
+import { getDatabaseConfig } from './config/database.config';
+import { loadFeatureFlags } from './config/feature-flags.config';
+
+const featureFlags = loadFeatureFlags();
 import { DebuggingModule } from './debugging/debugging.module';
 
 @Module({
   imports: [
+    ConfigModule.forRoot({ isGlobal: true }),
+    TypeOrmModule.forRoot(getDatabaseConfig()),
+    ScheduleModule.forRoot(),
     SearchModule,
+    ...(featureFlags.ENABLE_RATE_LIMITING ? [RateLimitingModule] : []),
     DebuggingModule,
   ],
   controllers: [AppController],
-  providers: [],
+  providers: featureFlags.ENABLE_RATE_LIMITING
+    ? [{ provide: APP_GUARD, useClass: QuotaGuard }]
+    : [],
 })
-export class AppModule {}
+export class AppModule { }

src/assessment/assessment.module.ts

@@ -14,15 +14,14 @@ import { Module } from '@nestjs/common';
  * Registers the assessments module.
  */
 @Module({
-    imports: [TypeOrmModule.forFeature([Assessment, Question, AssessmentAttempt, Answer])],
-    controllers: [AssessmentsController],
-    providers: [
-        AssessmentsService,
-        QuestionBankService,
-        ScoreCalculationService,
-        FeedbackGenerationService,
-    ],
-    exports: [AssessmentsService],
+  imports: [TypeOrmModule.forFeature([Assessment, Question, AssessmentAttempt, Answer])],
+  controllers: [AssessmentsController],
+  providers: [
+    AssessmentsService,
+    QuestionBankService,
+    ScoreCalculationService,
+    FeedbackGenerationService,
+  ],
+  exports: [AssessmentsService],
 })
-export class AssessmentsModule {
-}
+export class AssessmentsModule {}

src/assessment/assessments.service.ts

@@ -14,11 +14,11 @@ import { Question } from './entities/question.entity';
  */
 @Injectable()
 export class AssessmentsService {
-    constructor(
+  constructor(
     @InjectRepository(Assessment)
-    private readonly assessmentRepo: Repository<Assessment>, 
+    private readonly assessmentRepo: Repository<Assessment>,
     @InjectRepository(AssessmentAttempt)
-    private readonly attemptRepo: Repository<AssessmentAttempt>, 
+    private readonly attemptRepo: Repository<AssessmentAttempt>,
     @InjectRepository(Answer)
     private readonly answerRepo: Repository<Answer>,
     private readonly scoringService: ScoreCalculationService,