multi: source index notif. from block notif.

This updates the index subscriber to use block notifications as the
source of index notifications.

blockchain/chain.go

@@ -747,18 +747,6 @@ func (b *BlockChain) connectBlock(node *blockNode, block, parent *dcrutil.Block,
 		return err
 	}
 
-	// Notify subscribed indexes of the connected block.
-	if b.indexSubscriber != nil {
-		b.indexSubscriber.Notify(&indexers.IndexNtfn{
-			NtfnType:          indexers.ConnectNtfn,
-			Block:             block,
-			Parent:            parent,
-			PrevScripts:       prevScripter,
-			IsTreasuryEnabled: isTreasuryEnabled,
-			Done:              make(chan bool),
-		})
-	}
-
 	// This node is now the end of the best chain.
 	b.bestChain.SetTip(node)
 	b.index.MaybePruneCachedTips(node)
@@ -796,6 +784,7 @@ func (b *BlockChain) connectBlock(node *blockNode, block, parent *dcrutil.Block,
 		Block:        block,
 		ParentBlock:  parent,
 		CheckTxFlags: checkTxFlags,
+		PrevScripts:  prevScripter,
 	})
 	b.chainLock.Lock()
 
@@ -958,18 +947,6 @@ func (b *BlockChain) disconnectBlock(node *blockNode, block, parent *dcrutil.Blo
 		return err
 	}
 
-	// Notify subscribed indexes of the disconnected block.
-	if b.indexSubscriber != nil {
-		b.indexSubscriber.Notify(&indexers.IndexNtfn{
-			NtfnType:          indexers.DisconnectNtfn,
-			Block:             block,
-			Parent:            parent,
-			PrevScripts:       prevScripter,
-			IsTreasuryEnabled: isTreasuryEnabled,
-			Done:              make(chan bool),
-		})
-	}
-
 	// This node's parent is now the end of the best chain.
 	b.bestChain.SetTip(node.parent)
 
@@ -990,6 +967,7 @@ func (b *BlockChain) disconnectBlock(node *blockNode, block, parent *dcrutil.Blo
 		Block:        block,
 		ParentBlock:  parent,
 		CheckTxFlags: checkTxFlags,
+		PrevScripts:  prevScripter,
 	})
 	b.chainLock.Lock()
 

blockchain/indexers/common.go

@@ -532,12 +532,18 @@ func recover(ctx context.Context, idx Indexer) error {
 			return err
 		}
 
+		isTreasuryEnabled, err := queryer.IsTreasuryAgendaActive(parentHash)
+		if err != nil {
+			return err
+		}
+
 		ntfn := &IndexNtfn{
-			NtfnType:    DisconnectNtfn,
-			Block:       block,
-			Parent:      parent,
-			PrevScripts: prevScripts,
-			Done:        make(chan bool),
+			NtfnType:          DisconnectNtfn,
+			Block:             block,
+			Parent:            parent,
+			IsTreasuryEnabled: isTreasuryEnabled,
+			PrevScripts:       prevScripts,
+			Done:              make(chan bool),
 		}
 
 		err = updateIndex(ctx, idx, ntfn)

blockchain/indexers/indexsubscriber.go

@@ -359,7 +359,9 @@ func (s *IndexSubscriber) Run(ctx context.Context) {
 				}
 			}
 
-			close(ntfn.Done)
+			if ntfn.Done != nil {
+				close(ntfn.Done)
+			}
 
 		case <-ctx.Done():
 			log.Infof("Index subscriber shutting down")

blockchain/notifications.go

@@ -8,6 +8,7 @@ package blockchain
 import (
 	"fmt"
 
+	"github.com/decred/dcrd/blockchain/v4/indexers"
 	"github.com/decred/dcrd/chaincfg/chainhash"
 	"github.com/decred/dcrd/dcrutil/v4"
 )
@@ -131,6 +132,10 @@ type BlockConnectedNtfnsData struct {
 	// CheckTxFlags represents the agendas to consider as active when checking
 	// transactions for the block that was connected.
 	CheckTxFlags AgendaFlags
+
+	// PrevScripts provides access to previous transaction scripts and their
+	// associated versions spent by the connected block.
+	PrevScripts indexers.PrevScripter
 }
 
 // BlockDisconnectedNtfnsData is the structure for data indicating information
@@ -146,6 +151,10 @@ type BlockDisconnectedNtfnsData struct {
 	// CheckTxFlags represents the agendas to consider as active when checking
 	// transactions for the block that was **disconnected**.
 	CheckTxFlags AgendaFlags
+
+	// PrevScripts provides access to previous transaction scripts and their
+	// associated versions spent by the disconnected block.
+	PrevScripts indexers.PrevScripter
 }
 
 // ReorganizationNtfnsData is the structure for data indicating information

server.go

@@ -2750,6 +2750,17 @@ func (s *server) handleBlockchainNotification(notification *blockchain.Notificat
 			s.bg.BlockConnected(block)
 		}
 
+		// Notify subscribed indexes of connected block.
+		if s.indexSubscriber != nil {
+			s.indexSubscriber.Notify(&indexers.IndexNtfn{
+				NtfnType:          indexers.ConnectNtfn,
+				Block:             block,
+				Parent:            parentBlock,
+				IsTreasuryEnabled: isTreasuryEnabled,
+				PrevScripts:       ntfn.PrevScripts,
+			})
+		}
+
 		// Proactively evict signature cache entries that are virtually
 		// guaranteed to no longer be useful.
 		s.proactivelyEvictSigCacheEntries(block.Height())
@@ -2865,6 +2876,17 @@ func (s *server) handleBlockchainNotification(notification *blockchain.Notificat
 			s.bg.BlockDisconnected(block)
 		}
 
+		// Notify subscribed indexes of disconnected block.
+		if s.indexSubscriber != nil {
+			s.indexSubscriber.Notify(&indexers.IndexNtfn{
+				NtfnType:          indexers.DisconnectNtfn,
+				Block:             block,
+				Parent:            parentBlock,
+				IsTreasuryEnabled: isTreasuryEnabled,
+				PrevScripts:       ntfn.PrevScripts,
+			})
+		}
+
 		// Notify registered websocket clients.
 		if r := s.rpcServer; r != nil {
 			// Filter and update the rebroadcast inventory.