database

database

A thin wrapper around GORM and the PostgreSQL driver that handles connection setup, pool configuration, health checks, and operates with configurable query logging.

Quick start

cfg := database.Config{
    Host:     "localhost",
    Port:     5432,
    Username: "myuser",
    Password: "mypassword",
    Name:     "mydb",
    SSLMode:  "disable",
}

db, err := database.New(cfg)
if err != nil {
    log.Fatal(err)
}
defer database.Close(db)

db is a *gorm.DB ready to use for all GORM operations.

Configuration

Log levels

Control how much GORM logs about the queries it runs.

// Development: log every query
cfg := database.Config{
    // ...
    LogLevel: database.LogInfo,
}

// Production: log errors only (or nothing)
cfg := database.Config{
    // ...
    LogLevel: database.LogError, // same as omitting the field
}

API

New(cfg Config) (*gorm.DB, error)

Validates the config, opens a connection, configures the pool, and pings the server. Returns an error if any step fails. On success it logs a single INFO line through log/slog.

Close(db *gorm.DB) error

Closes the underlying sql.DB. Safe to call with a nil argument (no-op). Typically deferred in main:

db, err := database.New(cfg)
// ...
defer func() {
    if err := database.Close(db); err != nil {
        log.Printf("closing database: %v", err)
    }
}()

HealthCheck(db *gorm.DB) error

Pings the database and returns a non-nil error if the connection is unhealthy. Intended for use in a /healthz or /readyz HTTP handler:

func readyzHandler(db *gorm.DB) http.HandlerFunc {
    return func(w http.ResponseWriter, r *http.Request) {
        if err := database.HealthCheck(db); err != nil {
            http.Error(w, "database unavailable", http.StatusServiceUnavailable)
            return
        }
        w.WriteHeader(http.StatusOK)
    }
}

Connection pool tuning

cfg := database.Config{
    // ...
    MaxIdleConns:           5,
    MaxOpenConns:           25,
    MaxConnLifetimeSeconds: 300, // 5 minutes
}

Any pool field left at 0 is skipped so the driver's own default applies.

Testing

Unit tests cover Config.Validate, Config.DSN, gormLogLevel mapping, and the lifecycle functions (New, Close, HealthCheck) without requiring a running database. Run them with:

go test ./database/...

Integration tests that need a real PostgreSQL instance can be gated with a build tag or by checking an environment variable:

func TestIntegration(t *testing.T) {
    dsn := os.Getenv("TEST_DATABASE_URL")
    if dsn == "" {
        t.Skip("TEST_DATABASE_URL not set")
    }
    // ...
}