stack-performance/analyzers/ApiResponseTimeAnalyzer.js

A comprehensive application stack analyzer that evaluates MEAN, MERN, and other Node.js-based applications across 15 performance criteria

const BaseAnalyzer = require('./BaseAnalyzer');

/**
 * API Response Time Analyzer with algorithmic scoring
 */
class ApiResponseTimeAnalyzer extends BaseAnalyzer {
  constructor(stackInfo, projectPath) {
    super(stackInfo, projectPath, 'API Response Time');
  }

  async analyze() {
    const factors = [];

    // Factor 1: Framework Efficiency (35%)
    const frameworkScore = this.analyzeFrameworkEfficiency();
    factors.push({ score: frameworkScore, weight: 0.35 });

    // Factor 2: Database Query Optimization (25%)
    const dbOptScore = this.analyzeDatabaseOptimization();
    factors.push({ score: dbOptScore, weight: 0.25 });

    // Factor 3: Middleware Overhead (25%)
    const middlewareScore = this.analyzeMiddlewareEfficiency();
    factors.push({ score: middlewareScore, weight: 0.25 });

    // Factor 4: Response Compression (15%)
    const compressionScore = this.analyzeCompressionUsage();
    factors.push({ score: compressionScore, weight: 0.15 });

    const finalScore = this.calculateWeightedScore(factors);
    
    const details = {
      frameworkEfficiency: frameworkScore,
      databaseOptimization: dbOptScore,
      middlewareEfficiency: middlewareScore,
      compressionUsage: compressionScore,
      stackType: this.stackInfo.type
    };

    return this.createResult(finalScore, details, this.generateRecommendations(finalScore));
  }

  analyzeFrameworkEfficiency() {
    const { technologies } = this.stackInfo;
    let score = 60;
    
    if (technologies.includes('Fastify')) score += 25; // Highly optimized
    if (technologies.includes('Express.js')) score += 20; // Good performance
    if (technologies.includes('Koa')) score += 18; // Lightweight
    
    return Math.min(100, score);
  }

  analyzeDatabaseOptimization() {
    let score = 60;
    if (this.hasDependency('mongoose')) {
      score += 15;
      // Check for connection pooling indicators
      if (this.findFiles('**/config/**/*.js').length > 0) score += 10;
    }
    if (this.hasDependency('mongodb')) score += 12;
    return Math.min(100, score);
  }

  analyzeMiddlewareEfficiency() {
    let score = 70;
    if (this.hasDependency('helmet')) score += 5; // Security without major overhead
    if (this.hasDependency('cors')) score += 3;
    if (this.hasDependency('compression')) score += 8; // Actually improves response time
    return Math.min(100, score);
  }

  analyzeCompressionUsage() {
    let score = 50;
    if (this.hasDependency('compression')) score += 30;
    if (this.hasDependency('gzip')) score += 25;
    return Math.min(100, score);
  }

  generateRecommendations(score) {
    const recommendations = [];
    if (score < 70) {
      recommendations.push('Consider using Fastify for better performance');
      recommendations.push('Implement response compression middleware');
    }
    return recommendations;
  }
}

module.exports = ApiResponseTimeAnalyzer;