feat: backend service

integration/testenv/postgres.go

@@ -0,0 +1,122 @@
+package testenv
+
+import (
+	"context"
+	"fmt"
+	"net/url"
+	"strconv"
+	"testing"
+	"time"
+
+	"github.com/testcontainers/testcontainers-go"
+	tcpostgres "github.com/testcontainers/testcontainers-go/modules/postgres"
+	tcnetwork "github.com/testcontainers/testcontainers-go/network"
+	"github.com/testcontainers/testcontainers-go/wait"
+)
+
+const (
+	pgImage    = "postgres:16-alpine"
+	pgUser     = "galaxy"
+	pgPassword = "galaxy"
+	pgDatabase = "galaxy_backend"
+	pgSchema   = "backend"
+	pgStartup  = 90 * time.Second
+)
+
+// Postgres holds a running Postgres testcontainer reachable from both
+// the host (DSN with localhost-mapped port) and from another container
+// on the same Docker network (HostInNetworkDSN).
+type Postgres struct {
+	container *tcpostgres.PostgresContainer
+	HostDSN   string
+	NetworkDSN string
+}
+
+// StartPostgres boots a postgres:16-alpine container, returns DSNs for
+// both host and in-network access, and registers a t.Cleanup to
+// terminate the container.
+func StartPostgres(t *testing.T, network string) *Postgres {
+	t.Helper()
+	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Minute)
+	defer cancel()
+
+	opts := []testcontainers.ContainerCustomizer{
+		tcpostgres.WithDatabase(pgDatabase),
+		tcpostgres.WithUsername(pgUser),
+		tcpostgres.WithPassword(pgPassword),
+		testcontainers.WithWaitStrategy(
+			wait.ForLog("database system is ready to accept connections").
+				WithOccurrence(2).
+				WithStartupTimeout(pgStartup),
+		),
+	}
+	if network != "" {
+		opts = append(opts, tcnetwork.WithNetwork([]string{"postgres"}, &testcontainers.DockerNetwork{Name: network}))
+	}
+
+	container, err := tcpostgres.Run(ctx, pgImage, opts...)
+	if err != nil {
+		t.Skipf("postgres testcontainer unavailable: %v", err)
+	}
+	t.Cleanup(func() {
+		if err := testcontainers.TerminateContainer(container); err != nil {
+			t.Logf("terminate postgres: %v", err)
+		}
+	})
+
+	hostDSN, err := container.ConnectionString(ctx, "sslmode=disable")
+	if err != nil {
+		t.Fatalf("postgres host DSN: %v", err)
+	}
+	hostDSN, err = withSearchPath(hostDSN, pgSchema)
+	if err != nil {
+		t.Fatalf("postgres host DSN search_path: %v", err)
+	}
+
+	networkDSN := ""
+	if network != "" {
+		networkDSN = buildInNetworkDSN("postgres", 5432, pgUser, pgPassword, pgDatabase, pgSchema)
+	}
+
+	return &Postgres{
+		container:  container,
+		HostDSN:    hostDSN,
+		NetworkDSN: networkDSN,
+	}
+}
+
+func withSearchPath(dsn, schema string) (string, error) {
+	parsed, err := url.Parse(dsn)
+	if err != nil {
+		return "", err
+	}
+	q := parsed.Query()
+	q.Set("search_path", schema)
+	if q.Get("sslmode") == "" {
+		q.Set("sslmode", "disable")
+	}
+	parsed.RawQuery = q.Encode()
+	return parsed.String(), nil
+}
+
+func buildInNetworkDSN(host string, port int, user, password, db, schema string) string {
+	u := &url.URL{
+		Scheme:   "postgres",
+		User:     url.UserPassword(user, password),
+		Host:     fmt.Sprintf("%s:%d", host, port),
+		Path:     "/" + db,
+		RawQuery: "sslmode=disable&search_path=" + schema,
+	}
+	return u.String()
+}
+
+// HostPort renders a host:port pair so other testenv files can reuse
+// the same formatting.
+func HostPort(host string, port int) string {
+	return fmt.Sprintf("%s:%d", host, port)
+}
+
+// FormatPort returns the decimal representation of port.
+func FormatPort(port int) string {
+	return strconv.Itoa(port)
+}