WIP: support native sql config

config.go

@@ -1840,6 +1840,14 @@ func (c *Config) graphDatabaseDir() string {
 func (c *Config) ImplementationConfig(
 	interceptor signal.Interceptor) *ImplementationCfg {
 
+	// Create a default database builder.
+	dbBuilder := NewDefaultDatabaseBuilder(c, ltndLog)
+
+	// Use native sql db builder if specified.
+	if c.DB.Backend == lncfg.NativeSQLBackend {
+		dbBuilder = NewDefaultDatabaseBuilder(c, ltndLog)
+	}
+
 	// If we're using a remote signer, we still need the base wallet as a
 	// watch-only source of chain and address data. But we don't need any
 	// private key material in that btcwallet base wallet.
@@ -1849,12 +1857,10 @@ func (c *Config) ImplementationConfig(
 			c.RemoteSigner.MigrateWatchOnly,
 		)
 		return &ImplementationCfg{
-			GrpcRegistrar:     rpcImpl,
-			RestRegistrar:     rpcImpl,
-			ExternalValidator: rpcImpl,
-			DatabaseBuilder: NewDefaultDatabaseBuilder(
-				c, ltndLog,
-			),
+			GrpcRegistrar:       rpcImpl,
+			RestRegistrar:       rpcImpl,
+			ExternalValidator:   rpcImpl,
+			DatabaseBuilder:     dbBuilder,
 			WalletConfigBuilder: rpcImpl,
 			ChainControlBuilder: rpcImpl,
 		}
@@ -1865,7 +1871,7 @@ func (c *Config) ImplementationConfig(
 		GrpcRegistrar:       defaultImpl,
 		RestRegistrar:       defaultImpl,
 		ExternalValidator:   defaultImpl,
-		DatabaseBuilder:     NewDefaultDatabaseBuilder(c, ltndLog),
+		DatabaseBuilder:     dbBuilder,
 		WalletConfigBuilder: defaultImpl,
 		ChainControlBuilder: defaultImpl,
 	}

config_builder_db.go

@@ -0,0 +1,58 @@
+package lnd
+
+import (
+	"context"
+
+	"github.com/btcsuite/btclog"
+)
+
+// SQLDatabaseBuilder is a type that builds the SQL database backends for lnd,
+type SQLDatabaseBuilder struct {
+	cfg    *Config
+	logger btclog.Logger
+}
+
+// Compile time assertion that SQLDatabaseBuilder implements DatabaseBuilder.
+var _ DatabaseBuilder = (*SQLDatabaseBuilder)(nil)
+
+// NewSQLDatabaseBuilder returns a new instance of the SQL database builder.
+func NewSQLDatabaseBuilder(cfg *Config,
+	logger btclog.Logger) *SQLDatabaseBuilder {
+
+	return &SQLDatabaseBuilder{
+		cfg:    cfg,
+		logger: logger,
+	}
+}
+
+// BuildDatabase...
+func (d *SQLDatabaseBuilder) BuildDatabase(
+	ctx context.Context) (*DatabaseInstances, func(), error) {
+
+	// TODO(yy): Fix the dup logs.
+	d.logger.Infof("Opening database, this might take a few minutes...")
+
+	// Get the default database builder.
+	//
+	// TODO(yy): remove it once we have migrated all kvdb to native sql.
+	defaultBuiler := NewDefaultDatabaseBuilder(d.cfg, d.logger)
+
+	// Build the default database instance. Though the database could be
+	// SQL, the actual data store still uses key-value format.
+	dbs, cleanUp, err := defaultBuiler.BuildDatabase(ctx)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	// // Build the SQL database instance.
+	// sqlDB, err := NewSQLDB(d.cfg)
+
+	// // Map the database instances to the SQL database instances.
+	// dbs.InvoiceDB = sqlDB.NewInvoiceDB(d.cfg)
+	// dbs.PaymentDB = sqlDB.NewPaymentStore(d.cfg)
+
+	// TODO(yy): overwrite more sql tables here
+	// NOTE(yy): all the mappings should be removed eventually.
+
+	return dbs, cleanUp, nil
+}

lncfg/db.go

@@ -14,6 +14,7 @@ import (
 	"github.com/lightningnetwork/lnd/kvdb/sqlite"
 	"github.com/lightningnetwork/lnd/lnrpc"
 	"github.com/lightningnetwork/lnd/lnwallet/btcwallet"
+	"github.com/lightningnetwork/lnd/sqldb"
 )
 
 const (
@@ -33,6 +34,7 @@ const (
 	EtcdBackend                = "etcd"
 	PostgresBackend            = "postgres"
 	SqliteBackend              = "sqlite"
+	NativeSQLBackend           = "sql"
 	DefaultBatchCommitInterval = 500 * time.Millisecond
 
 	defaultPostgresMaxConnections = 50
@@ -66,6 +68,17 @@ const (
 	NSNeutrinoDB = "neutrinodb"
 )
 
+// KVDB holds the config values for kvdb backend.
+//
+//nolint:lll
+type KVDB struct {
+	Backend  string           `long:"backend" description:"The selected database backend." hidden:"true"`
+	Bolt     *kvdb.BoltConfig `group:"kvdb.bolt" namespace:"bolt" description:"Bolt settings."`
+	Etcd     *etcd.Config     `group:"kvdb.etcd" namespace:"etcd" description:"Etcd settings."`
+	Postgres *postgres.Config `group:"kvdb.postgres" namespace:"postgres" description:"Postgres settings."`
+	Sqlite   *sqlite.Config   `group:"kvdb.sqlite" namespace:"sqlite" description:"Sqlite settings."`
+}
+
 // DB holds database configuration for LND.
 //
 //nolint:lll
@@ -74,19 +87,20 @@ type DB struct {
 
 	BatchCommitInterval time.Duration `long:"batch-commit-interval" description:"The maximum duration the channel graph batch schedulers will wait before attempting to commit a batch of pending updates. This can be tradeoff database contenion for commit latency."`
 
-	Etcd *etcd.Config `group:"etcd" namespace:"etcd" description:"Etcd settings."`
-
-	Bolt *kvdb.BoltConfig `group:"bolt" namespace:"bolt" description:"Bolt settings."`
-
-	Postgres *postgres.Config `group:"postgres" namespace:"postgres" description:"Postgres settings."`
-
-	Sqlite *sqlite.Config `group:"sqlite" namespace:"sqlite" description:"Sqlite settings."`
-
 	NoGraphCache bool `long:"no-graph-cache" description:"Don't use the in-memory graph cache for path finding. Much slower but uses less RAM. Can only be used with a bolt database backend."`
 
 	PruneRevocation bool `long:"prune-revocation" description:"Run the optional migration that prunes the revocation logs to save disk space."`
 
 	NoRevLogAmtData bool `long:"no-rev-log-amt-data" description:"If set, the to-local and to-remote output amounts of revoked commitment transactions will not be stored in the revocation log. Note that once this data is lost, a watchtower client will not be able to back up the revoked state."`
+
+	KVDB      *KVDB         `group:"kvdb" namespace:"kvdb" description:"key-value database settings."`
+	NativeSQL *sqldb.Config `group:"sql" namespace:"sql" description:"Native SQL settings."`
+
+	// Deprecated fields.
+	Etcd     *etcd.Config     `group:"etcd" namespace:"etcd" description:"Etcd settings." hidden:"true"`
+	Bolt     *kvdb.BoltConfig `group:"bolt" namespace:"bolt" description:"Bolt settings." hidden:"true"`
+	Postgres *postgres.Config `group:"postgres" namespace:"postgres" description:"Postgres settings." hidden:"true"`
+	Sqlite   *sqlite.Config   `group:"sqlite" namespace:"sqlite" description:"Sqlite settings." hidden:"true"`
 }
 
 // DefaultDB creates and returns a new default DB config.
@@ -127,6 +141,11 @@ func (db *DB) Validate() error {
 			return fmt.Errorf("etcd host must be set")
 		}
 
+	case NativeSQLBackend:
+		if err := db.NativeSQL.Validate(); err != nil {
+			return fmt.Errorf("native sql: %w", err)
+		}
+
 	default:
 		return fmt.Errorf("unknown backend, must be either '%v', "+
 			"'%v', '%v' or '%v'", BoltBackend, EtcdBackend,

sqldb/config.go

@@ -0,0 +1,49 @@
+package sqldb
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/lightningnetwork/lnd/kvdb/postgres"
+	"github.com/lightningnetwork/lnd/kvdb/sqlite"
+)
+
+const (
+	PostgresBackend = "postgres"
+	SqliteBackend   = "sqlite"
+)
+
+var (
+	ErrMissingConfig  = errors.New("missing backend config")
+	ErrUnknownBackend = errors.New("unknown backend")
+)
+
+//nolint:lll
+type Config struct {
+	Backend string `long:"backend" description:"The selected database backend." hidden:"true"`
+
+	Postgres *postgres.Config `group:"sql.postgres" namespace:"postgres" description:"Postgres settings."`
+
+	Sqlite *sqlite.Config `group:"sql.sqlite" namespace:"sqlite" description:"Sqlite settings."`
+}
+
+func (c *Config) Validate() error {
+	switch c.Backend {
+	case PostgresBackend:
+		if c.Postgres == nil {
+			return fmt.Errorf("%w for postgres", ErrMissingConfig)
+		}
+
+		return c.Postgres.Validate()
+
+	case SqliteBackend:
+		if c.Sqlite == nil {
+			return fmt.Errorf("%w for sqlite", ErrMissingConfig)
+		}
+
+		return c.Sqlite.Validate()
+
+	default:
+		return fmt.Errorf("%w: %v", ErrUnknownBackend, c.Backend)
+	}
+}