The very basic client app, not adapted for mobiles.

client/internal/services/core/database/transaction.go

@@ -0,0 +1,79 @@
+package database
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+
+	"bunker/client/internal/services/core"
+
+	"github.com/jmoiron/sqlx"
+)
+
+type transaction struct {
+	transaction *sqlx.Tx
+}
+
+func (d *database) Transaction(ctx context.Context) (core.DatabaseTransaction, error) {
+	txn, err := d.db.BeginTxx(ctx, nil)
+	if err != nil {
+		return nil, fmt.Errorf("%w: starting transaction: %w", core.ErrDatabase, err)
+	}
+
+	txHandler := &transaction{
+		transaction: txn,
+	}
+
+	return txHandler, nil
+}
+
+func (t *transaction) Apply(steps ...core.TransactionFunc) error {
+	for stepNumber, stepFunc := range steps {
+		if err := stepFunc(t.transaction); err != nil {
+			slog.Error(
+				"Error occurred.",
+				"step", stepNumber,
+				"error", err.Error(),
+				"module", "core/database",
+				"subsystem", "transaction",
+			)
+
+			if rollbackErr := t.transaction.Rollback(); rollbackErr != nil {
+				slog.Error(
+					"Transaction rollback failed.",
+					"error", err.Error(),
+					"module", "core/database",
+					"subsystem", "transaction",
+				)
+
+				return fmt.Errorf("%w: transaction rollback: %w", core.ErrDatabase, rollbackErr)
+			}
+
+			return err
+		}
+	}
+
+	if err := t.transaction.Commit(); err != nil {
+		slog.Error(
+			"Transaction commit failed.",
+			"error", err.Error(),
+			"module", "core/database",
+			"subsystem", "transaction",
+		)
+
+		if rollbackErr := t.transaction.Rollback(); rollbackErr != nil {
+			slog.Error(
+				"Transaction rollback failed.",
+				"error", err.Error(),
+				"module", "core/database",
+				"subsystem", "transaction",
+			)
+
+			return fmt.Errorf("%w: transaction rollback: %w", core.ErrDatabase, rollbackErr)
+		}
+
+		return fmt.Errorf("%w: transaction commit: %w", core.ErrDatabase, err)
+	}
+
+	return nil
+}