graph/db+sqldb: pass set of outpoints to SQL

This commit adds a new GetChannelsByOutpoints query which takes a slice
of outpoint strings. This lets us then update PruneGraph to use
paginated calls to GetChannelsByOutpoints instead of making one DB call
per outpoint.

graph/db/sql_store.go

@@ -93,7 +93,7 @@ type SQLQueries interface {
 	CreateChannel(ctx context.Context, arg sqlc.CreateChannelParams) (int64, error)
 	AddV1ChannelProof(ctx context.Context, arg sqlc.AddV1ChannelProofParams) (sql.Result, error)
 	GetChannelBySCID(ctx context.Context, arg sqlc.GetChannelBySCIDParams) (sqlc.GraphChannel, error)
-	GetChannelByOutpoint(ctx context.Context, outpoint string) (sqlc.GetChannelByOutpointRow, error)
+	GetChannelsByOutpoints(ctx context.Context, outpoints []string) ([]sqlc.GetChannelsByOutpointsRow, error)
 	GetChannelsBySCIDRange(ctx context.Context, arg sqlc.GetChannelsBySCIDRangeParams) ([]sqlc.GetChannelsBySCIDRangeRow, error)
 	GetChannelBySCIDWithPolicies(ctx context.Context, arg sqlc.GetChannelBySCIDWithPoliciesParams) (sqlc.GetChannelBySCIDWithPoliciesRow, error)
 	GetChannelAndNodesBySCID(ctx context.Context, arg sqlc.GetChannelAndNodesBySCIDParams) (sqlc.GetChannelAndNodesBySCIDRow, error)
@@ -2365,22 +2365,9 @@ func (s *SQLStore) PruneGraph(spentOutputs []*wire.OutPoint,
 		prunedNodes []route.Vertex
 	)
 	err := s.db.ExecTx(ctx, sqldb.WriteTxOpt(), func(db SQLQueries) error {
-		for _, outpoint := range spentOutputs {
-			// TODO(elle): potentially optimize this by using
-			//  sqlc.slice() once that works for both SQLite and
-			//  Postgres.
-			//
-			// NOTE: this fetches channels for all protocol
-			// versions.
-			row, err := db.GetChannelByOutpoint(
-				ctx, outpoint.String(),
-			)
-			if errors.Is(err, sql.ErrNoRows) {
-				continue
-			} else if err != nil {
-				return fmt.Errorf("unable to fetch channel: %w",
-					err)
-			}
+		// Define the callback function for processing each channel.
+		channelCallback := func(ctx context.Context,
+			row sqlc.GetChannelsByOutpointsRow) error {
 
 			node1, node2, err := buildNodeVertices(
 				row.Node1Pubkey, row.Node2Pubkey,
@@ -2404,9 +2391,19 @@ func (s *SQLStore) PruneGraph(spentOutputs []*wire.OutPoint,
 			}
 
 			closedChans = append(closedChans, info)
+
+			return nil
 		}
 
-		err := db.UpsertPruneLogEntry(
+		err := s.forEachChanInOutpoints(
+			ctx, db, spentOutputs, channelCallback,
+		)
+		if err != nil {
+			return fmt.Errorf("unable to fetch channels by "+
+				"outpoints: %w", err)
+		}
+
+		err = db.UpsertPruneLogEntry(
 			ctx, sqlc.UpsertPruneLogEntryParams{
 				BlockHash:   blockHash[:],
 				BlockHeight: int64(blockHeight),
@@ -2442,6 +2439,35 @@ func (s *SQLStore) PruneGraph(spentOutputs []*wire.OutPoint,
 	return closedChans, prunedNodes, nil
 }
 
+// forEachChanInOutpoints is a helper function that executes a paginated
+// query to fetch channels by their outpoints and applies the given call-back
+// to each.
+//
+// NOTE: this fetches channels for all protocol versions.
+func (s *SQLStore) forEachChanInOutpoints(ctx context.Context, db SQLQueries,
+	outpoints []*wire.OutPoint, cb func(ctx context.Context,
+		row sqlc.GetChannelsByOutpointsRow) error) error {
+
+	// Create a wrapper that uses the transaction's db instance to execute
+	// the query.
+	queryWrapper := func(ctx context.Context,
+		pageOutpoints []string) ([]sqlc.GetChannelsByOutpointsRow,
+		error) {
+
+		return db.GetChannelsByOutpoints(ctx, pageOutpoints)
+	}
+
+	// Define the conversion function from Outpoint to string.
+	outpointToString := func(outpoint *wire.OutPoint) string {
+		return outpoint.String()
+	}
+
+	return sqldb.ExecutePagedQuery(
+		ctx, s.cfg.PaginationCfg, outpoints, outpointToString,
+		queryWrapper, cb,
+	)
+}
+
 // ChannelView returns the verifiable edge information for each active channel
 // within the known channel graph. The set of UTXOs (along with their scripts)
 // returned are the ones that need to be watched on chain to detect channel

sqldb/sqlc/graph.sql.go

@@ -358,46 +358,6 @@ func (q *Queries) GetChannelAndNodesBySCID(ctx context.Context, arg GetChannelAn
 	return i, err
 }
 
-const getChannelByOutpoint = `-- name: GetChannelByOutpoint :one
-SELECT
-    c.id, c.version, c.scid, c.node_id_1, c.node_id_2, c.outpoint, c.capacity, c.bitcoin_key_1, c.bitcoin_key_2, c.node_1_signature, c.node_2_signature, c.bitcoin_1_signature, c.bitcoin_2_signature,
-    n1.pub_key AS node1_pubkey,
-    n2.pub_key AS node2_pubkey
-FROM graph_channels c
-    JOIN graph_nodes n1 ON c.node_id_1 = n1.id
-    JOIN graph_nodes n2 ON c.node_id_2 = n2.id
-WHERE c.outpoint = $1
-`
-
-type GetChannelByOutpointRow struct {
-	GraphChannel GraphChannel
-	Node1Pubkey  []byte
-	Node2Pubkey  []byte
-}
-
-func (q *Queries) GetChannelByOutpoint(ctx context.Context, outpoint string) (GetChannelByOutpointRow, error) {
-	row := q.db.QueryRowContext(ctx, getChannelByOutpoint, outpoint)
-	var i GetChannelByOutpointRow
-	err := row.Scan(
-		&i.GraphChannel.ID,
-		&i.GraphChannel.Version,
-		&i.GraphChannel.Scid,
-		&i.GraphChannel.NodeID1,
-		&i.GraphChannel.NodeID2,
-		&i.GraphChannel.Outpoint,
-		&i.GraphChannel.Capacity,
-		&i.GraphChannel.BitcoinKey1,
-		&i.GraphChannel.BitcoinKey2,
-		&i.GraphChannel.Node1Signature,
-		&i.GraphChannel.Node2Signature,
-		&i.GraphChannel.Bitcoin1Signature,
-		&i.GraphChannel.Bitcoin2Signature,
-		&i.Node1Pubkey,
-		&i.Node2Pubkey,
-	)
-	return i, err
-}
-
 const getChannelByOutpointWithPolicies = `-- name: GetChannelByOutpointWithPolicies :one
 SELECT
     c.id, c.version, c.scid, c.node_id_1, c.node_id_2, c.outpoint, c.capacity, c.bitcoin_key_1, c.bitcoin_key_2, c.node_1_signature, c.node_2_signature, c.bitcoin_1_signature, c.bitcoin_2_signature,

sqldb/sqlc/querier.go

@@ -35,7 +35,6 @@ type Querier interface {
 	FilterInvoices(ctx context.Context, arg FilterInvoicesParams) ([]Invoice, error)
 	GetAMPInvoiceID(ctx context.Context, setID []byte) (int64, error)
 	GetChannelAndNodesBySCID(ctx context.Context, arg GetChannelAndNodesBySCIDParams) (GetChannelAndNodesBySCIDRow, error)
-	GetChannelByOutpoint(ctx context.Context, outpoint string) (GetChannelByOutpointRow, error)
 	GetChannelByOutpointWithPolicies(ctx context.Context, arg GetChannelByOutpointWithPoliciesParams) (GetChannelByOutpointWithPoliciesRow, error)
 	GetChannelBySCID(ctx context.Context, arg GetChannelBySCIDParams) (GraphChannel, error)
 	GetChannelBySCIDWithPolicies(ctx context.Context, arg GetChannelBySCIDWithPoliciesParams) (GetChannelBySCIDWithPoliciesRow, error)

sqldb/sqlc/queries/graph.sql

@@ -242,16 +242,6 @@ FROM graph_channels c
 WHERE c.outpoint IN
     (sqlc.slice('outpoints')/*SLICE:outpoints*/);
 
--- name: GetChannelByOutpoint :one
-SELECT
-    sqlc.embed(c),
-    n1.pub_key AS node1_pubkey,
-    n2.pub_key AS node2_pubkey
-FROM graph_channels c
-    JOIN graph_nodes n1 ON c.node_id_1 = n1.id
-    JOIN graph_nodes n2 ON c.node_id_2 = n2.id
-WHERE c.outpoint = $1;
-
 -- name: GetChannelAndNodesBySCID :one
 SELECT
     c.*,