the rest

internal/db/data.go

@@ -0,0 +1,68 @@
+package db
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"os"
+	"strconv"
+	"time"
+
+	_ "github.com/jackc/pgx/v5/stdlib"
+)
+
+func OpenDB(ctx context.Context) (*sql.DB, error) {
+	dsn := os.Getenv("DATABASE_URL")
+	if dsn == "" {
+		host := getenv("DB_HOST", "localhost")
+		port := getenv("DB_PORT", "5432")
+		user := getenv("DB_USER", "party")
+		pass := getenv("DB_PASS", "secret")
+		name := getenv("DB_NAME", "partydb")
+		ssl := getenv("DB_SSLMODE", "disable")
+		dsn = fmt.Sprintf("postgres://%s:%s@%s:%s/%s?sslmode=%s", user, pass, host, port, name, ssl)
+	}
+
+	db, err := sql.Open("pgx", dsn)
+	if err != nil {
+		return nil, err
+	}
+
+	// Connection pool tuning
+	if v := os.Getenv("DB_MAX_OPEN_CONNS"); v != "" {
+		if n, err := strconv.Atoi(v); err == nil {
+			db.SetMaxOpenConns(n)
+		}
+	} else {
+		db.SetMaxOpenConns(25)
+	}
+	if v := os.Getenv("DB_MAX_IDLE_CONNS"); v != "" {
+		if n, err := strconv.Atoi(v); err == nil {
+			db.SetMaxIdleConns(n)
+		}
+	} else {
+		db.SetMaxIdleConns(25)
+	}
+	if v := os.Getenv("DB_CONN_MAX_LIFETIME"); v != "" {
+		if d, err := time.ParseDuration(v); err == nil {
+			db.SetConnMaxLifetime(d)
+		}
+	} else {
+		db.SetConnMaxLifetime(30 * time.Minute)
+	}
+
+	ctxPing, cancel := context.WithTimeout(ctx, 5*time.Second)
+	defer cancel()
+	if err := db.PingContext(ctxPing); err != nil {
+		db.Close()
+		return nil, err
+	}
+	return db, nil
+}
+
+func getenv(key, def string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return def
+}