initial commit

internal/pkg/database/database.go

@@ -0,0 +1,99 @@
+package database
+
+import (
+	"database/sql"
+	"fmt"
+	"time"
+
+	"github.com/rs/zerolog"
+	"gorm.io/driver/postgres"
+	"gorm.io/gorm"
+
+	"base/config"
+	"base/pkg/metrics"
+)
+
+// NewRWDatabaseConnection creates a new database connection
+func NewRWDatabaseConnection(cfg *config.AppConfig, logger zerolog.Logger, metric *metrics.Metrics) (*gorm.DB, error) {
+	start := time.Now()
+
+	lg := logger.
+		With().
+		Str("module", "database").
+		Int("maxOpenConnection", cfg.Database.MaxOpenConns).
+		Int("maxIdleConnection", cfg.Database.MaxIdleConns).
+		Logger()
+
+	gormConfig := &gorm.Config{Logger: NewGormLogger(logger, time.Second*5)}
+
+	wrDB, sqlDB, err := wr(cfg, gormConfig)
+	if err != nil {
+		fmt.Println("[DATABASE CONNECTION ERROR]Failed to connect to database", err.Error())
+		metric.RecordDatabaseQuery("ConnectWR", "database", time.Since(start), err)
+
+		lg.Error().
+			Err(err).
+			Msg("failed to connect to database")
+
+		return nil, err
+	}
+
+	metric.RecordDatabaseQuery("ConnectWR", "database", time.Since(start), nil)
+
+	// Start monitoring connection pool metrics
+	go monitorConnectionPool(sqlDB, metric, logger)
+
+	duration := time.Since(start)
+	metric.RecordDatabaseQuery("Connect", "database", duration, nil)
+
+	lg.Info().Msg("Database connection established")
+
+	return wrDB, nil
+}
+
+func wr(config *config.AppConfig, gormConfig *gorm.Config) (*gorm.DB, *sql.DB, error) {
+	// PostgreSQL DSN format: postgres://user:password@host:port/dbname?sslmode=disable
+	dsn := fmt.Sprintf(
+		"host=%s user=%s password=%s dbname=%s port=%d sslmode=%s TimeZone=UTC",
+		config.PgDatabaseConfig.Host,
+		config.PgDatabaseConfig.User,
+		config.PgDatabaseConfig.Password,
+		config.PgDatabaseConfig.Name,
+		config.PgDatabaseConfig.Port,
+		config.PgDatabaseConfig.SSLMode,
+	)
+
+	db, err := gorm.Open(postgres.Open(dsn), gormConfig)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// Get the underlying sql.DB
+	sqlDB, err := db.DB()
+	if err != nil {
+		return nil, nil, err
+	}
+
+	sqlDB.SetMaxIdleConns(int(config.PgDatabaseConfig.PoolConfig.MinConn))
+	sqlDB.SetMaxOpenConns(int(config.PgDatabaseConfig.PoolConfig.MaxConn))
+
+	// Parse and set connection timeouts from config
+	// TODO: this is not type safe
+	if config.PgDatabaseConfig.PoolConfig.MaxConnIdleTime.String() != "" {
+		if idleTime, parseDurationErr := time.ParseDuration(config.PgDatabaseConfig.PoolConfig.MaxConnIdleTime.String()); parseDurationErr == nil {
+			sqlDB.SetConnMaxIdleTime(idleTime)
+		} else {
+			sqlDB.SetConnMaxIdleTime(5 * time.Minute)
+		}
+	}
+
+	if config.PgDatabaseConfig.PoolConfig.MaxConnLifetime.String() != "" {
+		if lifetime, parseDurationErr := time.ParseDuration(config.PgDatabaseConfig.PoolConfig.MaxConnLifetime.String()); parseDurationErr == nil {
+			sqlDB.SetConnMaxLifetime(lifetime)
+		} else {
+			sqlDB.SetConnMaxLifetime(30 * time.Minute)
+		}
+	}
+
+	return db, sqlDB, nil
+}