Alerting: Add alertmanager integration tests (#100106)

pkg/tests/alertmanager/postgres.go

@@ -0,0 +1,41 @@
+package alertmanager
+
+import (
+	"os"
+
+	"github.com/grafana/e2e"
+)
+
+const (
+	defaultPostgresImage = "postgres:16.4"
+	postgresHTTPPort     = 5432
+)
+
+// GetDefaultImage returns the Docker image to use to run the Postgres..
+func GetPostgresImage() string {
+	if img := os.Getenv("POSTGRES_IMAGE"); img != "" {
+		return img
+	}
+
+	return defaultPostgresImage
+}
+
+type PostgresService struct {
+	*e2e.HTTPService
+}
+
+func NewPostgresService(name string, envVars map[string]string) *PostgresService {
+	svc := &PostgresService{
+		HTTPService: e2e.NewHTTPService(
+			name,
+			GetPostgresImage(),
+			nil,
+			nil,
+			postgresHTTPPort,
+		),
+	}
+
+	svc.SetEnvVars(envVars)
+
+	return svc
+}