add env files

config.go

@@ -0,0 +1,216 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"strings"
+
+	"github.com/joho/godotenv"
+)
+
+type Environment string
+
+const (
+	Development Environment = "development"
+	Staging     Environment = "staging"
+	Production  Environment = "production"
+)
+
+type Config struct {
+	Environment Environment
+	DatabaseURL string
+	JWTSecret   string
+	Port        string
+	GinMode     string
+	LogLevel    string
+	Debug       bool
+}
+
+// LoadConfig loads configuration with proper environment file precedence
+func LoadConfig() *Config {
+	// Load environment files in priority order
+	loadEnvironmentFiles()
+
+	// Get environment
+	env := getEnvironment()
+
+	// Load configuration
+	config := &Config{
+		Environment: env,
+		DatabaseURL: getEnv("DATABASE_URL", getDefaultDatabaseURL(env)),
+		JWTSecret:   getRequiredEnv("JWT_SECRET"),
+		Port:        getEnv("PORT", "8080"),
+		GinMode:     getGinMode(env),
+		LogLevel:    getLogLevel(env),
+		Debug:       env == Development,
+	}
+
+	// Log configuration (without sensitive data)
+	logConfig(config)
+
+	return config
+}
+
+// loadEnvironmentFiles loads environment files in priority order
+func loadEnvironmentFiles() {
+	// Get environment first (from system env or default)
+	env := getEnvironmentFromSystem()
+
+	log.Printf("🔍 Detected environment: %s", env)
+
+	// Define file loading order (later files override earlier ones)
+	files := []string{
+		".env",                      // Base configuration
+		fmt.Sprintf(".env.%s", env), // Environment-specific
+	}
+
+	// Load files in order
+	for _, file := range files {
+		if _, err := os.Stat(file); err == nil {
+			if err := godotenv.Load(file); err != nil {
+				log.Printf("⚠️  Warning: Could not load %s: %v", file, err)
+			} else {
+				log.Printf("✅ Loaded: %s", file)
+			}
+		} else {
+			log.Printf("❌ Not found: %s", file)
+		}
+	}
+}
+
+// getEnvironmentFromSystem gets environment from system variables only
+func getEnvironmentFromSystem() string {
+	// Check if ENVIRONMENT is already set
+	if env := os.Getenv("ENVIRONMENT"); env != "" {
+		return strings.ToLower(env)
+	}
+
+	// Fallback detection
+	if ginMode := os.Getenv("GIN_MODE"); ginMode == "release" {
+		return "production"
+	}
+
+	return "development"
+}
+
+// getEnvironment gets the current environment
+func getEnvironment() Environment {
+	env := strings.ToLower(getEnv("ENVIRONMENT", "development"))
+
+	switch env {
+	case "development", "dev":
+		return Development
+	case "staging", "stage":
+		return Staging
+	case "production", "prod":
+		return Production
+	default:
+		log.Printf("⚠️  Unknown environment '%s', defaulting to development", env)
+		return Development
+	}
+}
+
+// getGinMode returns the appropriate Gin mode for the environment
+func getGinMode(env Environment) string {
+	switch env {
+	case Production, Staging:
+		return "release"
+	case Development:
+		return "debug"
+	default:
+		return "debug"
+	}
+}
+
+// getLogLevel returns the appropriate log level for the environment
+func getLogLevel(env Environment) string {
+	switch env {
+	case Production:
+		return "warn"
+	case Staging:
+		return "info"
+	case Development:
+		return "debug"
+	default:
+		return "debug"
+	}
+}
+
+// getDefaultDatabaseURL returns default database URL for environment
+func getDefaultDatabaseURL(env Environment) string {
+	switch env {
+	case Development:
+		return "postgres://postgres:password@localhost:5432/counter_db?sslmode=disable"
+	case Staging:
+		return "postgres://postgres:password@postgres:5432/counter_db?sslmode=disable"
+	case Production:
+		return "postgres://postgres:password@postgres:5432/counter_db?sslmode=require"
+	default:
+		return "postgres://postgres:password@localhost:5432/counter_db?sslmode=disable"
+	}
+}
+
+// getEnv gets environment variable with default value
+func getEnv(key, defaultValue string) string {
+	if value := os.Getenv(key); value != "" {
+		return value
+	}
+	return defaultValue
+}
+
+// getRequiredEnv gets required environment variable
+func getRequiredEnv(key string) string {
+	value := os.Getenv(key)
+	if value == "" {
+		log.Fatalf("❌ Required environment variable %s is not set", key)
+	}
+	return value
+}
+
+// logConfig logs configuration (without sensitive data)
+func logConfig(config *Config) {
+	// Environment banner
+	log.Printf("")
+	log.Printf("╔══════════════════════════════════════════════════════════════╗")
+	log.Printf("║                    COUNTER APPLICATION                      ║")
+	log.Printf("║                                                              ║")
+	log.Printf("║  🌍 ENVIRONMENT: %-15s                              ║", strings.ToUpper(string(config.Environment)))
+	log.Printf("║  🚀 MODE: %-20s                              ║", config.GinMode)
+	log.Printf("║  🔧 DEBUG: %-20s                              ║", fmt.Sprintf("%t", config.Debug))
+	log.Printf("║  📊 LOG LEVEL: %-15s                              ║", config.LogLevel)
+	log.Printf("║  🌐 PORT: %-20s                              ║", config.Port)
+	log.Printf("║                                                              ║")
+	log.Printf("║  📁 Configuration Files Loaded:                              ║")
+	log.Printf("║     • .env (base configuration)                              ║")
+	log.Printf("║     • .env.%s (environment-specific)                     ║", config.Environment)
+	log.Printf("║                                                              ║")
+	log.Printf("║  🔐 Security:                                                ║")
+	log.Printf("║     • Database: %s ║", maskDatabaseURL(config.DatabaseURL))
+	log.Printf("║     • JWT Secret: %s ║", maskSecret(config.JWTSecret))
+	log.Printf("║                                                              ║")
+	log.Printf("╚══════════════════════════════════════════════════════════════╝")
+	log.Printf("")
+}
+
+// maskDatabaseURL masks sensitive parts of database URL
+func maskDatabaseURL(url string) string {
+	// Simple masking - replace password with ***
+	if strings.Contains(url, "://") {
+		parts := strings.Split(url, "://")
+		if len(parts) == 2 {
+			// Replace password in connection string
+			masked := strings.Replace(parts[1], ":", ":***@", 1)
+			return parts[0] + "://" + masked
+		}
+	}
+	return "***"
+}
+
+// maskSecret masks JWT secret for logging
+func maskSecret(secret string) string {
+	if len(secret) <= 8 {
+		return "***"
+	}
+	return secret[:4] + "***" + secret[len(secret)-4:]
+}