🔧 Add environment variable validation utility

code/websites/pokedex.online/server/utils/env-validator.js

@@ -0,0 +1,167 @@
+/**
+ * Environment Variable Validation
+ * 
+ * Validates required environment variables at startup and provides
+ * helpful error messages for production deployments.
+ */
+
+/**
+ * Required environment variables for production
+ */
+const REQUIRED_ENV_VARS = {
+  // Server Configuration
+  NODE_ENV: {
+    required: true,
+    description: 'Environment mode (development, production)',
+    validate: (val) => ['development', 'production', 'test'].includes(val)
+  },
+  PORT: {
+    required: true,
+    description: 'Server port number',
+    validate: (val) => !isNaN(parseInt(val)) && parseInt(val) > 0 && parseInt(val) < 65536
+  },
+  
+  // Optional but recommended for production
+  SESSION_SECRET: {
+    required: false,
+    description: 'Secret key for session encryption',
+    warn: (val) => !val || val.length < 32 ? 'SESSION_SECRET should be at least 32 characters for security' : null
+  },
+  FRONTEND_URL: {
+    required: false,
+    description: 'Frontend URL for CORS (required in production)',
+    warn: (val, env) => env.NODE_ENV === 'production' && !val ? 'FRONTEND_URL should be set in production for proper CORS' : null
+  },
+  
+  // Challonge OAuth (optional)
+  CHALLONGE_CLIENT_ID: {
+    required: false,
+    description: 'Challonge OAuth client ID'
+  },
+  CHALLONGE_CLIENT_SECRET: {
+    required: false,
+    description: 'Challonge OAuth client secret'
+  },
+  CHALLONGE_REDIRECT_URI: {
+    required: false,
+    description: 'OAuth redirect URI'
+  }
+};
+
+/**
+ * Validate environment variables
+ * @returns {Object} Validation result with errors and warnings
+ */
+export function validateEnvironment() {
+  const errors = [];
+  const warnings = [];
+  const missing = [];
+  
+  // Check required variables
+  for (const [key, config] of Object.entries(REQUIRED_ENV_VARS)) {
+    const value = process.env[key];
+    
+    // Check if required variable is missing
+    if (config.required && !value) {
+      errors.push(`Missing required environment variable: ${key} - ${config.description}`);
+      missing.push(key);
+      continue;
+    }
+    
+    // Validate value if present
+    if (value && config.validate && !config.validate(value)) {
+      errors.push(`Invalid value for ${key}: "${value}" - ${config.description}`);
+    }
+    
+    // Check for warnings
+    if (config.warn) {
+      const warning = config.warn(value, process.env);
+      if (warning) {
+        warnings.push(`${key}: ${warning}`);
+      }
+    }
+  }
+  
+  return {
+    valid: errors.length === 0,
+    errors,
+    warnings,
+    missing
+  };
+}
+
+/**
+ * Validate environment and exit if critical errors found
+ * @param {boolean} exitOnError - Whether to exit process on validation errors (default: true)
+ */
+export function validateOrExit(exitOnError = true) {
+  const result = validateEnvironment();
+  
+  // Print validation results
+  console.log('\n🔍 Environment Validation:');
+  console.log(`   NODE_ENV: ${process.env.NODE_ENV || 'not set'}`);
+  console.log(`   PORT: ${process.env.PORT || 'not set'}`);
+  
+  // Show errors
+  if (result.errors.length > 0) {
+    console.error('\n❌ Environment Validation Errors:');
+    result.errors.forEach(error => console.error(`   - ${error}`));
+    
+    if (result.missing.length > 0) {
+      console.error('\n💡 Tip: Create a .env file with these variables:');
+      result.missing.forEach(key => {
+        console.error(`   ${key}=your_value_here`);
+      });
+      console.error('\n   See .env.example for reference');
+    }
+    
+    if (exitOnError) {
+      console.error('\n❌ Server cannot start due to environment errors\n');
+      process.exit(1);
+    }
+  } else {
+    console.log('   ✅ All required variables present');
+  }
+  
+  // Show warnings
+  if (result.warnings.length > 0) {
+    console.warn('\n⚠️  Environment Warnings:');
+    result.warnings.forEach(warning => console.warn(`   - ${warning}`));
+  }
+  
+  console.log('');
+  return result;
+}
+
+/**
+ * Get configuration object with validated environment variables
+ * @returns {Object} Configuration object
+ */
+export function getConfig() {
+  return {
+    nodeEnv: process.env.NODE_ENV || 'development',
+    port: parseInt(process.env.PORT || '3001'),
+    isProduction: process.env.NODE_ENV === 'production',
+    isDevelopment: process.env.NODE_ENV === 'development',
+    
+    // Challonge OAuth
+    challonge: {
+      clientId: process.env.CHALLONGE_CLIENT_ID,
+      clientSecret: process.env.CHALLONGE_CLIENT_SECRET,
+      redirectUri: process.env.CHALLONGE_REDIRECT_URI,
+      configured: !!(process.env.CHALLONGE_CLIENT_ID && process.env.CHALLONGE_CLIENT_SECRET)
+    },
+    
+    // CORS
+    cors: {
+      origin: process.env.NODE_ENV === 'production'
+        ? process.env.FRONTEND_URL
+        : ['http://localhost:5173', 'http://localhost:5174', 'http://localhost:5175']
+    },
+    
+    // Security
+    session: {
+      secret: process.env.SESSION_SECRET || 'dev-secret-change-in-production'
+    }
+  };
+}