universe: rename interface BaseBackend to StorageBackend

Renamed interface to better reflect its broader usage. It now applies
to both issuance proof leaves and transfer proof leaves.

Author: ffranr

tapcfg/server.go

@@ -155,7 +155,8 @@ func genServerConfig(cfg *Config, cfgLogger btclog.Logger,
 		context.Background(), assetMintingStore,
 	)
 	uniArchiveCfg := universe.ArchiveConfig{
-		NewBaseTree: func(id universe.Identifier) universe.BaseBackend {
+		// nolint: lll
+		NewBaseTree: func(id universe.Identifier) universe.StorageBackend {
 			return tapdb.NewBaseUniverseTree(
 				uniDB, id,
 			)

tapdb/universe.go

@@ -380,11 +380,11 @@ type BatchedUniverseTree interface {
 	BatchedTx[BaseUniverseStore]
 }
 
-// BaseUniverseTree implements the persistent storage for the Base universe for
+// BaseUniverseTree implements the persistent storage for the universe for
 // a given asset. The minting outpoints stored of the asset are used to key
 // into the universe tree.
 //
-// NOTE: This implements the universe.Base interface.
+// NOTE: This implements the universe.StorageBackend interface.
 type BaseUniverseTree struct {
 	db BatchedUniverseTree
 
@@ -1192,4 +1192,4 @@ func (b *BaseUniverseTree) DeleteUniverse(ctx context.Context) (string, error) {
 	return b.smtNamespace, dbErr
 }
 
-var _ universe.BaseBackend = (*BaseUniverseTree)(nil)
+var _ universe.StorageBackend = (*BaseUniverseTree)(nil)

universe/archive.go

@@ -22,7 +22,7 @@ type ArchiveConfig struct {
 	// NewBaseTree returns a new base universe backend for the given
 	// identifier. This method always returns a new universe instance, even
 	// if the identifier has never been seen before.
-	NewBaseTree func(id Identifier) BaseBackend
+	NewBaseTree func(id Identifier) StorageBackend
 
 	// HeaderVerifier is used to verify the validity of the header for a
 	// genesis proof.
@@ -65,7 +65,7 @@ type Archive struct {
 
 	// baseUniverses is a map of all the current known base universe
 	// instances for the archive.
-	baseUniverses map[Identifier]BaseBackend
+	baseUniverses map[Identifier]StorageBackend
 
 	sync.RWMutex
 }
@@ -74,7 +74,7 @@ type Archive struct {
 func NewArchive(cfg ArchiveConfig) *Archive {
 	a := &Archive{
 		cfg:           cfg,
-		baseUniverses: make(map[Identifier]BaseBackend),
+		baseUniverses: make(map[Identifier]StorageBackend),
 	}
 
 	return a
@@ -87,7 +87,7 @@ func (a *Archive) Close() error {
 
 // fetchUniverse returns the base universe instance for the passed identifier.
 // The universe will be loaded in on demand if it has not been seen before.
-func (a *Archive) fetchUniverse(id Identifier) BaseBackend {
+func (a *Archive) fetchUniverse(id Identifier) StorageBackend {
 	a.Lock()
 	defer a.Unlock()
 
@@ -103,12 +103,12 @@ func (a *Archive) fetchUniverse(id Identifier) BaseBackend {
 // uniFetcher takes a base universe ID, and returns the base universe
 // backend associated with the ID.
 type uniFetcher interface {
-	fetchUniverse(id Identifier) BaseBackend
+	fetchUniverse(id Identifier) StorageBackend
 }
 
 // uniAction is a function that takes a base universe backend, and does
 // something to it, returning a type T and an error.
-type uniAction[T any] func(BaseBackend) (T, error)
+type uniAction[T any] func(StorageBackend) (T, error)
 
 // withUni is a helper function that performs an action on a universe instance,
 // returning a generic result.
@@ -705,7 +705,7 @@ func (a *Archive) FetchLeaves(ctx context.Context,
 		id.StringForLog())
 
 	return withUni(
-		a, id, func(uni BaseBackend) ([]Leaf, error) {
+		a, id, func(uni StorageBackend) ([]Leaf, error) {
 			return uni.FetchLeaves(ctx)
 		},
 	)

universe/interface.go

@@ -398,13 +398,11 @@ func (i *Proof) VerifyRoot(expectedRoot mssmt.Node) bool {
 		mssmt.IsEqualNode(reconstructedRoot, expectedRoot)
 }
 
-// BaseBackend is the backend storage interface for a base universe. The
-// backend can be used to store issuance profs, retrieve them, and also fetch
-// the set of keys and leaves stored within the universe.
-//
-// TODO(roasbeef): gRPC service to match this, think about the REST mapping
-type BaseBackend interface {
-	// RootNode returns the root node for a given base universe.
+// StorageBackend defines the storage interface for a universe. It supports
+// storing and retrieving proofs, as well as fetching the set of keys and leaves
+// contained in the universe.
+type StorageBackend interface {
+	// RootNode returns the root node for a given universe.
 	RootNode(context.Context) (mssmt.Node, string, error)
 
 	// UpsertProofLeaf inserts or updates a proof leaf within the universe
@@ -430,7 +428,7 @@ type BaseBackend interface {
 	// FetchLeaves retrieves all leaves from the universe tree.
 	FetchLeaves(ctx context.Context) ([]Leaf, error)
 
-	// DeleteUniverse deletes all leaves, and the root, for a given base
+	// DeleteUniverse deletes all leaves, and the root, for a given
 	// universe.
 	DeleteUniverse(ctx context.Context) (string, error)
 }
@@ -477,10 +475,9 @@ type MultiverseLeaf struct {
 	*mssmt.LeafNode
 }
 
-// MultiverseArchive is an interface used to keep track of the set of universe
-// roots that we know of. The BaseBackend interface is used to interact with a
-// particular base universe, while this is used to obtain aggregate information
-// about the universes.
+// MultiverseArchive is an interface for tracking the set of known universe
+// roots. While the StorageBackend interface operates on a single universe, this
+// interface provides aggregate access across multiple universes.
 type MultiverseArchive interface {
 	// RootNodes returns the complete set of known root nodes for the set
 	// of assets tracked in the base Universe.
@@ -779,15 +776,15 @@ type CommittedIssuanceProof struct {
 type ChainCommitter interface {
 	// CommitUniverse takes a Universe and returns a new commitment to that
 	// Universe in the main chain.
-	CommitUniverse(universe BaseBackend) (*Commitment, error)
+	CommitUniverse(universe StorageBackend) (*Commitment, error)
 }
 
 // Canonical is an interface that allows a caller to query for the latest
 // canonical Universe information related to an asset.
 //
 // TODO(roasbeef): sync methods too, divide into read/write?
 type Canonical interface {
-	BaseBackend
+	StorageBackend
 
 	// Query returns a fully proved response for the target base key.
 	Query(context.Context, LeafKey) (*CommittedIssuanceProof, error)