Release v0.1.0

vendor/github.com/btcsuite/btcwallet/wtxmgr/migrations.go

@@ -0,0 +1,110 @@
+package wtxmgr
+
+import (
+	"github.com/btcsuite/btcwallet/walletdb"
+	"github.com/btcsuite/btcwallet/walletdb/migration"
+)
+
+// versions is a list of the different database versions. The last entry should
+// reflect the latest database state. If the database happens to be at a version
+// number lower than the latest, migrations will be performed in order to catch
+// it up.
+var versions = []migration.Version{
+	{
+		Number:    1,
+		Migration: nil,
+	},
+	{
+		Number:    2,
+		Migration: dropTransactionHistory,
+	},
+}
+
+// getLatestVersion returns the version number of the latest database version.
+func getLatestVersion() uint32 {
+	return versions[len(versions)-1].Number
+}
+
+// MigrationManager is an implementation of the migration.Manager interface that
+// will be used to handle migrations for the address manager. It exposes the
+// necessary parameters required to successfully perform migrations.
+type MigrationManager struct {
+	ns walletdb.ReadWriteBucket
+}
+
+// A compile-time assertion to ensure that MigrationManager implements the
+// migration.Manager interface.
+var _ migration.Manager = (*MigrationManager)(nil)
+
+// NewMigrationManager creates a new migration manager for the transaction
+// manager. The given bucket should reflect the top-level bucket in which all
+// of the transaction manager's data is contained within.
+func NewMigrationManager(ns walletdb.ReadWriteBucket) *MigrationManager {
+	return &MigrationManager{ns: ns}
+}
+
+// Name returns the name of the service we'll be attempting to upgrade.
+//
+// NOTE: This method is part of the migration.Manager interface.
+func (m *MigrationManager) Name() string {
+	return "wallet transaction manager"
+}
+
+// Namespace returns the top-level bucket of the service.
+//
+// NOTE: This method is part of the migration.Manager interface.
+func (m *MigrationManager) Namespace() walletdb.ReadWriteBucket {
+	return m.ns
+}
+
+// CurrentVersion returns the current version of the service's database.
+//
+// NOTE: This method is part of the migration.Manager interface.
+func (m *MigrationManager) CurrentVersion(ns walletdb.ReadBucket) (uint32, error) {
+	if ns == nil {
+		ns = m.ns
+	}
+	return fetchVersion(m.ns)
+}
+
+// SetVersion sets the version of the service's database.
+//
+// NOTE: This method is part of the migration.Manager interface.
+func (m *MigrationManager) SetVersion(ns walletdb.ReadWriteBucket,
+	version uint32) error {
+
+	if ns == nil {
+		ns = m.ns
+	}
+	return putVersion(m.ns, version)
+}
+
+// Versions returns all of the available database versions of the service.
+//
+// NOTE: This method is part of the migration.Manager interface.
+func (m *MigrationManager) Versions() []migration.Version {
+	return versions
+}
+
+// dropTransactionHistory is a migration that attempts to recreate the
+// transaction store with a clean state.
+func dropTransactionHistory(ns walletdb.ReadWriteBucket) error {
+	log.Info("Dropping wallet transaction history")
+
+	// To drop the store's transaction history, we'll need to remove all of
+	// the relevant descendant buckets and key/value pairs.
+	if err := deleteBuckets(ns); err != nil {
+		return err
+	}
+	if err := ns.Delete(rootMinedBalance); err != nil {
+		return err
+	}
+
+	// With everything removed, we'll now recreate our buckets.
+	if err := createBuckets(ns); err != nil {
+		return err
+	}
+
+	// Finally, we'll insert a 0 value for our mined balance.
+	return putMinedBalance(ns, 0)
+}