cmd/api-server/main.go

@@ -15,6 +15,7 @@ import (
 
 	"github.com/joho/godotenv"
 	"github.com/robindittmar/dttmr-api/internal/api/router"
+	"github.com/robindittmar/dttmr-api/internal/database"
 	"github.com/robindittmar/dttmr-api/internal/telemetry"
 )
 
@@ -22,6 +23,7 @@ type Config struct {
 	Environment  string
 	Port         int
 	OTLPEndpoint string
+	DatabaseURL  string
 }
 
 func main() {
@@ -62,6 +64,18 @@ func run(serviceName string, serviceVersion string) error {
 		}
 	}()
 
+	db, err := database.New(context.Background(), cfg.DatabaseURL)
+	if err != nil {
+		slog.Error("Failed to initialize database", slog.Any("error", err))
+		return err
+	}
+	defer func() {
+		err := db.Close()
+		if err != nil {
+			slog.Error("Failed to close database connection", slog.Any("error", err))
+		}
+	}()
+
 	srv := makeServer(cfg)
 	go func() {
 		slog.Info("Starting http server", "addr", srv.Addr)
@@ -103,6 +117,7 @@ func loadConfig() *Config {
 	envFlag := flag.String("env", "development", "environment to use")
 	portFlag := flag.Int("port", 8080, "port to listen on")
 	otlpEndpointFlag := flag.String("otlp-endpoint", "localhost:4317", "otlp endpoint")
+	databaseUrlFlag := flag.String("database-url", "postgres://postgres:postgres@localhost:5432/postgres?sslmode=disable", "database connection string")
 
 	flag.Parse()
 
@@ -110,11 +125,13 @@ func loadConfig() *Config {
 		Environment:  *envFlag,
 		Port:         *portFlag,
 		OTLPEndpoint: *otlpEndpointFlag,
+		DatabaseURL:  *databaseUrlFlag,
 	}
 
 	assignStringFromEnv("DTTMR_ENVIRONMENT", &cfg.Environment)
 	assignIntFromEnv("DTTMR_PORT", &cfg.Port)
 	assignStringFromEnv("DTTMR_OTLP_ENDPOINT", &cfg.OTLPEndpoint)
+	assignStringFromEnv("DTTMR_DATABASE_URL", &cfg.DatabaseURL)
 
 	return cfg
 }

go.mod

@@ -3,6 +3,7 @@ module github.com/robindittmar/dttmr-api
 go 1.26
 
 require (
+	github.com/jackc/pgx/v5 v5.10.0
 	github.com/joho/godotenv v1.5.1
 	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.69.0
 	go.opentelemetry.io/otel v1.44.0
@@ -21,11 +22,15 @@ require (
 	github.com/go-logr/stdr v1.2.2 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.29.0 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
+	github.com/jackc/puddle/v2 v2.2.2 // indirect
 	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.44.0 // indirect
 	go.opentelemetry.io/otel/metric v1.44.0 // indirect
 	go.opentelemetry.io/proto/otlp v1.10.0 // indirect
 	golang.org/x/net v0.56.0 // indirect
+	golang.org/x/sync v0.21.0 // indirect
 	golang.org/x/sys v0.46.0 // indirect
 	golang.org/x/text v0.39.0 // indirect
 	google.golang.org/genproto/googleapis/api v0.0.0-20260706201446-f0a921348800 // indirect

internal/database/db.go

@@ -0,0 +1,29 @@
+package database
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"time"
+
+	_ "github.com/jackc/pgx/v5/stdlib"
+)
+
+func New(ctx context.Context, connURL string) (*sql.DB, error) {
+	db, err := sql.Open("pgx", connURL)
+	if err != nil {
+		return nil, fmt.Errorf("failed to connect to database: %w", err)
+	}
+
+	db.SetMaxOpenConns(10)
+	db.SetMaxIdleConns(10)
+
+	db.SetConnMaxLifetime(5 * time.Minute)
+	db.SetConnMaxIdleTime(5 * time.Minute)
+
+	if err := db.PingContext(ctx); err != nil {
+		return nil, fmt.Errorf("database unreachable: %w", err)
+	}
+
+	return db, nil
+}