move fireEvents to ApplyBlock

blockchain/reactor.go

@@ -284,7 +284,6 @@ FOR_LOOP:
 
 					bcR.store.SaveBlock(first, firstParts, second.LastCommit)
 
-					// TODO: should we be firing events? need to fire NewBlock events manually ...
 					// NOTE: we could improve performance if we
 					// didn't make the app commit to disk every block
 					// ... but we would need a way to get the hash without it persisting

consensus/common_test.go

@@ -264,7 +264,7 @@ func newConsensusStateWithConfigAndBlockStore(thisConfig *cfg.Config, state sm.S
 	evpool := types.MockEvidencePool{}
 
 	// Make ConsensusReactor
-	stateDB := dbm.NewMemDB() // XXX !!
+	stateDB := dbm.NewMemDB()
 	blockExec := sm.NewBlockExecutor(stateDB, log.TestingLogger(), proxyAppConnCon, mempool, evpool)
 	cs := NewConsensusState(thisConfig.Consensus, state, blockExec, blockStore, mempool, evpool)
 	cs.SetLogger(log.TestingLogger())

consensus/state.go

@@ -1203,8 +1203,6 @@ func (cs *ConsensusState) finalizeCommit(height int64) {
 	// Create a copy of the state for staging
 	// and an event cache for txs
 	stateCopy := cs.state.Copy()
-	txEventBuffer := types.NewTxEventBuffer(cs.eventBus, int(block.NumTxs))
-	cs.blockExec.SetTxEventPublisher(txEventBuffer)
 
 	// Execute and commit the block, update and save the state, and update the mempool.
 	// NOTE: the block.AppHash wont reflect these txs until the next block
@@ -1221,22 +1219,6 @@ func (cs *ConsensusState) finalizeCommit(height int64) {
 
 	fail.Fail() // XXX
 
-	// Fire event for new block.
-	// NOTE: If we fail before firing, these events will never fire
-	//
-	// TODO: Either
-	//	* Fire before persisting state, in ApplyBlock
-	//	* Fire on start up if we haven't written any new WAL msgs
-	//   Both options mean we may fire more than once. Is that fine ?
-	cs.eventBus.PublishEventNewBlock(types.EventDataNewBlock{block})
-	cs.eventBus.PublishEventNewBlockHeader(types.EventDataNewBlockHeader{block.Header})
-	err = txEventBuffer.Flush()
-	if err != nil {
-		cs.Logger.Error("Failed to flush event buffer", "err", err)
-	}
-
-	fail.Fail() // XXX
-
 	// NewHeightStep!
 	cs.updateToState(stateCopy)
 

node/node.go

@@ -291,6 +291,7 @@ func NewNode(config *cfg.Config,
 	eventBus.SetLogger(logger.With("module", "events"))
 
 	// services which will be publishing and/or subscribing for messages (events)
+	blockExec.SetEventBus(eventBus)
 	consensusReactor.SetEventBus(eventBus)
 
 	// Transaction indexing

state/execution.go

@@ -26,8 +26,8 @@ type BlockExecutor struct {
 	// execute the app against this
 	proxyApp proxy.AppConnConsensus
 
-	// tx events
-	txEventPublisher types.TxEventPublisher
+	// events
+	eventBus types.BlockEventPublisher
 
 	// update these with block results after commit
 	mempool types.Mempool
@@ -36,27 +36,29 @@ type BlockExecutor struct {
 	logger log.Logger
 }
 
-// NewBlockExecutor returns a new BlockExecutor.
+// NewBlockExecutor returns a new BlockExecutor with a NopEventBus.
+// Call SetEventBus to provide one.
 func NewBlockExecutor(db dbm.DB, logger log.Logger, proxyApp proxy.AppConnConsensus,
 	mempool types.Mempool, evpool types.EvidencePool) *BlockExecutor {
 	return &BlockExecutor{
-		db:               db,
-		proxyApp:         proxyApp,
-		txEventPublisher: types.NopEventBus{},
-		mempool:          mempool,
-		evpool:           evpool,
-		logger:           logger,
+		db:       db,
+		proxyApp: proxyApp,
+		eventBus: types.NopEventBus{},
+		mempool:  mempool,
+		evpool:   evpool,
+		logger:   logger,
 	}
 }
 
-// SetTxEventPublisher - set the transaction event publisher. If not called,
-// it defaults to types.NopEventBus.
-func (blockExec *BlockExecutor) SetTxEventPublisher(txEventPublisher types.TxEventPublisher) {
-	blockExec.txEventPublisher = txEventPublisher
+// SetEventBus - sets the event bus for publishing block related events.
+// If not called, it defaults to types.NopEventBus.
+func (blockExec *BlockExecutor) SetEventBus(eventBus types.BlockEventPublisher) {
+	blockExec.eventBus = eventBus
 }
 
 // ApplyBlock validates the block against the state, executes it against the app,
-// commits it, and saves the block and state. It's the only function that needs to be called
+// fires the relevent events, commits the app, and saves the new state and responses.
+// It's the only function that needs to be called
 // from outside this package to process and commit an entire block.
 // It takes a blockID to avoid recomputing the parts hash.
 func (blockExec *BlockExecutor) ApplyBlock(s State, blockID types.BlockID, block *types.Block) (State, error) {
@@ -70,8 +72,6 @@ func (blockExec *BlockExecutor) ApplyBlock(s State, blockID types.BlockID, block
 		return s, ErrProxyAppConn(err)
 	}
 
-	fireEvents(blockExec.txEventPublisher, block, abciResponses)
-
 	fail.Fail() // XXX
 
 	// save the results before we commit
@@ -97,6 +97,12 @@ func (blockExec *BlockExecutor) ApplyBlock(s State, blockID types.BlockID, block
 	s.AppHash = appHash
 	SaveState(blockExec.db, s)
 
+	fail.Fail() // XXX
+
+	// events are fired after everything else
+	// NOTE: if we crash between Commit and Save, events wont be fired during replay
+	fireEvents(blockExec.logger, blockExec.eventBus, block, abciResponses)
+
 	return s, nil
 }
 
@@ -354,15 +360,27 @@ func updateState(s State, blockID types.BlockID, header *types.Header,
 	}, nil
 }
 
-func fireEvents(txEventPublisher types.TxEventPublisher, block *types.Block, abciResponses *ABCIResponses) {
+// Fire NewBlock, NewBlockHeader.
+// Fire TxEvent for every tx.
+// NOTE: if Tendermint crashes before commit, some or all of these events may be published again.
+func fireEvents(logger log.Logger, eventBus types.BlockEventPublisher, block *types.Block, abciResponses *ABCIResponses) {
+	// NOTE: do we still need this buffer ?
+	txEventBuffer := types.NewTxEventBuffer(eventBus, int(block.NumTxs))
 	for i, tx := range block.Data.Txs {
-		txEventPublisher.PublishEventTx(types.EventDataTx{types.TxResult{
+		txEventBuffer.PublishEventTx(types.EventDataTx{types.TxResult{
 			Height: block.Height,
 			Index:  uint32(i),
 			Tx:     tx,
 			Result: *(abciResponses.DeliverTx[i]),
 		}})
 	}
+
+	eventBus.PublishEventNewBlock(types.EventDataNewBlock{block})
+	eventBus.PublishEventNewBlockHeader(types.EventDataNewBlockHeader{block.Header})
+	err := txEventBuffer.Flush()
+	if err != nil {
+		logger.Error("Failed to flush event buffer", "err", err)
+	}
 }
 
 //----------------------------------------------------------------------------------------------------

types/events.go

@@ -175,6 +175,13 @@ func QueryForEvent(eventType string) tmpubsub.Query {
 	return tmquery.MustParse(fmt.Sprintf("%s='%s'", EventTypeKey, eventType))
 }
 
+// BlockEventPublisher publishes all block related events
+type BlockEventPublisher interface {
+	PublishEventNewBlock(block EventDataNewBlock) error
+	PublishEventNewBlockHeader(header EventDataNewBlockHeader) error
+	PublishEventTx(EventDataTx) error
+}
+
 type TxEventPublisher interface {
 	PublishEventTx(EventDataTx) error
 }