New DALC API

block/manager.go

@@ -3,6 +3,7 @@ package block
 import (
 	"context"
 	"fmt"
+	"sync"
 	"sync/atomic"
 	"time"
 
@@ -12,6 +13,7 @@ import (
 	"github.com/tendermint/tendermint/crypto/merkle"
 	"github.com/tendermint/tendermint/proxy"
 	tmtypes "github.com/tendermint/tendermint/types"
+	"go.uber.org/multierr"
 
 	"github.com/celestiaorg/optimint/config"
 	"github.com/celestiaorg/optimint/da"
@@ -22,6 +24,9 @@ import (
 	"github.com/celestiaorg/optimint/types"
 )
 
+// defaultDABlockTime is used only if DABlockTime is not configured for manager
+const defaultDABlockTime = 30 * time.Second
+
 // Manager is responsible for aggregating transactions into blocks.
 type Manager struct {
 	lastState state.State
@@ -36,15 +41,21 @@ type Manager struct {
 
 	dalc      da.DataAvailabilityLayerClient
 	retriever da.BlockRetriever
+	// daHeight is the height of the latest processed DA block
+	daHeight uint64
 
 	HeaderOutCh chan *types.Header
 	HeaderInCh  chan *types.Header
 
 	syncTarget uint64
 	blockInCh  chan *types.Block
-	retrieveCh chan uint64
 	syncCache  map[uint64]*types.Block
 
+	// retrieveMtx is used by retrieveCond
+	retrieveMtx *sync.Mutex
+	// retrieveCond is used to notify sync goroutine (SyncLoop) that it needs to retrieve data
+	retrieveCond *sync.Cond
+
 	logger log.Logger
 }
 
@@ -72,12 +83,20 @@ func NewManager(
 	if err != nil {
 		return nil, err
 	}
+	if s.DAHeight < conf.DAStartHeight {
+		s.DAHeight = conf.DAStartHeight
+	}
 
 	proposerAddress, err := getAddress(proposerKey)
 	if err != nil {
 		return nil, err
 	}
 
+	if conf.DABlockTime == 0 {
+		logger.Info("WARNING: using default DA block time", "DABlockTime", defaultDABlockTime)
+		conf.DABlockTime = defaultDABlockTime
+	}
+
 	exec := state.NewBlockExecutor(proposerAddress, conf.NamespaceID, genesis.ChainID, mempool, proxyApp, eventBus, logger)
 	if s.LastBlockHeight+1 == genesis.InitialHeight {
 		res, err := exec.InitChain(genesis)
@@ -100,13 +119,16 @@ func NewManager(
 		executor:    exec,
 		dalc:        dalc,
 		retriever:   dalc.(da.BlockRetriever), // TODO(tzdybal): do it in more gentle way (after MVP)
-		HeaderOutCh: make(chan *types.Header),
-		HeaderInCh:  make(chan *types.Header),
-		blockInCh:   make(chan *types.Block),
-		retrieveCh:  make(chan uint64),
+		daHeight:    s.DAHeight,
+		// channels are buffered to avoid blocking on input/output operations, buffer sizes are arbitrary
+		HeaderOutCh: make(chan *types.Header, 100),
+		HeaderInCh:  make(chan *types.Header, 100),
+		blockInCh:   make(chan *types.Block, 100),
+		retrieveMtx: new(sync.Mutex),
 		syncCache:   make(map[uint64]*types.Block),
 		logger:      logger,
 	}
+	agg.retrieveCond = sync.NewCond(agg.retrieveMtx)
 
 	return agg, nil
 }
@@ -142,8 +164,11 @@ func (m *Manager) AggregationLoop(ctx context.Context) {
 }
 
 func (m *Manager) SyncLoop(ctx context.Context) {
+	daTicker := time.NewTicker(m.conf.DABlockTime)
 	for {
 		select {
+		case <-daTicker.C:
+			m.retrieveCond.Signal()
 		case header := <-m.HeaderInCh:
 			m.logger.Debug("block header received", "height", header.Height, "hash", header.Hash())
 			newHeight := header.Height
@@ -153,14 +178,15 @@ func (m *Manager) SyncLoop(ctx context.Context) {
 			// it's handled gently in RetrieveLoop
 			if newHeight > currentHeight {
 				atomic.StoreUint64(&m.syncTarget, newHeight)
-				m.retrieveCh <- newHeight
+				m.retrieveCond.Signal()
 			}
 		case block := <-m.blockInCh:
 			m.logger.Debug("block body retrieved from DALC",
 				"height", block.Header.Height,
 				"hash", block.Hash(),
 			)
 			m.syncCache[block.Header.Height] = block
+			m.retrieveCond.Signal()
 			currentHeight := m.store.Height() // TODO(tzdybal): maybe store a copy in memory
 			b1, ok1 := m.syncCache[currentHeight+1]
 			b2, ok2 := m.syncCache[currentHeight+2]
@@ -181,6 +207,7 @@ func (m *Manager) SyncLoop(ctx context.Context) {
 					continue
 				}
 
+				newState.DAHeight = atomic.LoadUint64(&m.daHeight)
 				m.lastState = newState
 				err = m.store.UpdateState(m.lastState)
 				if err != nil {
@@ -195,50 +222,75 @@ func (m *Manager) SyncLoop(ctx context.Context) {
 	}
 }
 
+// RetrieveLoop is responsible for interacting with DA layer.
 func (m *Manager) RetrieveLoop(ctx context.Context) {
+	// waitCh is used to signal the retrieve loop, that it should process next blocks
+	// retrieveCond can be signalled in completely async manner, and goroutine below
+	// works as some kind of "buffer" for those signals
+	waitCh := make(chan interface{})
+	go func() {
+		for {
+			m.retrieveMtx.Lock()
+			m.retrieveCond.Wait()
+			waitCh <- nil
+			m.retrieveMtx.Unlock()
+			if ctx.Err() != nil {
+				return
+			}
+		}
+	}()
+
 	for {
 		select {
-		case <-m.retrieveCh:
-			target := atomic.LoadUint64(&m.syncTarget)
-			for h := m.store.Height() + 1; h <= target; h++ {
-				m.logger.Debug("trying to retrieve block from DALC", "height", h)
-				m.mustRetrieveBlock(ctx, h)
+		case <-waitCh:
+			for {
+				daHeight := atomic.LoadUint64(&m.daHeight)
+				m.logger.Debug("retrieve", "daHeight", daHeight)
+				err := m.processNextDABlock()
+				if err != nil {
+					m.logger.Error("failed to retrieve block from DALC", "daHeight", daHeight, "errors", err.Error())
+					break
+				}
+				atomic.AddUint64(&m.daHeight, 1)
 			}
 		case <-ctx.Done():
 			return
 		}
 	}
 }
 
-func (m *Manager) mustRetrieveBlock(ctx context.Context, height uint64) {
+func (m *Manager) processNextDABlock() error {
 	// TODO(tzdybal): extract configuration option
 	maxRetries := 10
+	daHeight := atomic.LoadUint64(&m.daHeight)
 
+	var err error
+	m.logger.Debug("trying to retrieve block from DA", "daHeight", daHeight)
 	for r := 0; r < maxRetries; r++ {
-		err := m.fetchBlock(ctx, height)
-		if err == nil {
-			return
+		blockResp, fetchErr := m.fetchBlock(daHeight)
+		if fetchErr != nil {
+			err = multierr.Append(err, fetchErr)
+			time.Sleep(100 * time.Millisecond)
+		} else {
+			for _, block := range blockResp.Blocks {
+				m.blockInCh <- block
+			}
+			return nil
 		}
-		// TODO(tzdybal): configuration option
-		// TODO(tzdybal): exponential backoff
-		time.Sleep(100 * time.Millisecond)
 	}
-	// TODO(tzdybal): this is only temporary solution, for MVP
-	panic("failed to retrieve block with DALC")
+	return err
 }
 
-func (m *Manager) fetchBlock(ctx context.Context, height uint64) error {
+func (m *Manager) fetchBlock(daHeight uint64) (da.ResultRetrieveBlocks, error) {
 	var err error
-	blockRes := m.retriever.RetrieveBlock(height)
+	blockRes := m.retriever.RetrieveBlocks(daHeight)
 	switch blockRes.Code {
-	case da.StatusSuccess:
-		m.blockInCh <- blockRes.Block
 	case da.StatusError:
 		err = fmt.Errorf("failed to retrieve block: %s", blockRes.Message)
 	case da.StatusTimeout:
 		err = fmt.Errorf("timeout during retrieve block: %s", blockRes.Message)
 	}
-	return err
+	return blockRes, err
 }
 
 func (m *Manager) getRemainingSleep(start time.Time) time.Duration {
@@ -305,6 +357,7 @@ func (m *Manager) publishBlock(ctx context.Context) error {
 		return err
 	}
 
+	newState.DAHeight = atomic.LoadUint64(&m.daHeight)
 	m.lastState = newState
 	err = m.store.UpdateState(m.lastState)
 	if err != nil {
@@ -320,6 +373,7 @@ func (m *Manager) publishBlock(ctx context.Context) error {
 }
 
 func (m *Manager) broadcastBlock(ctx context.Context, block *types.Block) error {
+	m.logger.Debug("submitting block to DA layer", "height", block.Header.Height)
 	res := m.dalc.SubmitBlock(block)
 	if res.Code != da.StatusSuccess {
 		return fmt.Errorf("DA layer submission failed: %s", res.Message)

config/config.go

@@ -32,8 +32,13 @@ type NodeConfig struct {
 
 // BlockManagerConfig consists of all parameters required by BlockManagerConfig
 type BlockManagerConfig struct {
-	BlockTime   time.Duration `mapstructure:"block_time"`
-	NamespaceID [8]byte       `mapstructure:"namespace_id"`
+	// BlockTime defines how often new blocks are produced
+	BlockTime time.Duration `mapstructure:"block_time"`
+	// DABlockTime informs about block time of underlying data availability layer
+	DABlockTime time.Duration `mapstructure:"da_block_time"`
+	// DAStartHeight allows skipping first DAStartHeight-1 blocks when querying for blocks.
+	DAStartHeight uint64  `mapstructure:"da_start_height"`
+	NamespaceID   [8]byte `mapstructure:"namespace_id"`
 }
 
 func (nc *NodeConfig) GetViperConfig(v *viper.Viper) error {

da/da.go

@@ -25,6 +25,8 @@ type DAResult struct {
 	Code StatusCode
 	// Message may contain DA layer specific information (like DA block height/hash, detailed error message, etc)
 	Message string
+	// DAHeight informs about a height on Data Availability Layer for given result.
+	DAHeight uint64
 }
 
 // ResultSubmitBlock contains information returned from DA layer after block submission.
@@ -43,11 +45,11 @@ type ResultCheckBlock struct {
 	DataAvailable bool
 }
 
-type ResultRetrieveBlock struct {
+type ResultRetrieveBlocks struct {
 	DAResult
 	// Block is the full block retrieved from Data Availability Layer.
 	// If Code is not equal to StatusSuccess, it has to be nil.
-	Block *types.Block
+	Blocks []*types.Block
 }
 
 // DataAvailabilityLayerClient defines generic interface for DA layer block submission.
@@ -65,12 +67,12 @@ type DataAvailabilityLayerClient interface {
 	SubmitBlock(block *types.Block) ResultSubmitBlock
 
 	// CheckBlockAvailability queries DA layer to check data availability of block corresponding to given header.
-	CheckBlockAvailability(header *types.Header) ResultCheckBlock
+	CheckBlockAvailability(dataLayerHeight uint64) ResultCheckBlock
 }
 
 // BlockRetriever is additional interface that can be implemented by Data Availability Layer Client that is able to retrieve
 // block data from DA layer. This gives the ability to use it for block synchronization.
 type BlockRetriever interface {
-	// RetrieveBlock returns block at given height from data availability layer.
-	RetrieveBlock(height uint64) ResultRetrieveBlock
+	// RetrieveBlocks returns blocks at given data layer height from data availability layer.
+	RetrieveBlocks(dataLayerHeight uint64) ResultRetrieveBlocks
 }

da/grpc/grpc.go

@@ -75,12 +75,16 @@ func (d *DataAvailabilityLayerClient) SubmitBlock(block *types.Block) da.ResultS
 		}
 	}
 	return da.ResultSubmitBlock{
-		DAResult: da.DAResult{Code: da.StatusCode(resp.Result.Code), Message: resp.Result.Message},
+		DAResult: da.DAResult{
+			Code:     da.StatusCode(resp.Result.Code),
+			Message:  resp.Result.Message,
+			DAHeight: resp.Result.DataLayerHeight,
+		},
 	}
 }
 
-func (d *DataAvailabilityLayerClient) CheckBlockAvailability(header *types.Header) da.ResultCheckBlock {
-	resp, err := d.client.CheckBlockAvailability(context.TODO(), &dalc.CheckBlockAvailabilityRequest{Header: header.ToProto()})
+func (d *DataAvailabilityLayerClient) CheckBlockAvailability(dataLayerHeight uint64) da.ResultCheckBlock {
+	resp, err := d.client.CheckBlockAvailability(context.TODO(), &dalc.CheckBlockAvailabilityRequest{DataLayerHeight: dataLayerHeight})
 	if err != nil {
 		return da.ResultCheckBlock{DAResult: da.DAResult{Code: da.StatusError, Message: err.Error()}}
 	}
@@ -90,19 +94,27 @@ func (d *DataAvailabilityLayerClient) CheckBlockAvailability(header *types.Heade
 	}
 }
 
-func (d *DataAvailabilityLayerClient) RetrieveBlock(height uint64) da.ResultRetrieveBlock {
-	resp, err := d.client.RetrieveBlock(context.TODO(), &dalc.RetrieveBlockRequest{Height: height})
+func (d *DataAvailabilityLayerClient) RetrieveBlocks(dataLayerHeight uint64) da.ResultRetrieveBlocks {
+	resp, err := d.client.RetrieveBlocks(context.TODO(), &dalc.RetrieveBlocksRequest{DataLayerHeight: dataLayerHeight})
 	if err != nil {
-		return da.ResultRetrieveBlock{DAResult: da.DAResult{Code: da.StatusError, Message: err.Error()}}
+		return da.ResultRetrieveBlocks{DAResult: da.DAResult{Code: da.StatusError, Message: err.Error()}}
 	}
 
-	var b types.Block
-	err = b.FromProto(resp.Block)
-	if err != nil {
-		return da.ResultRetrieveBlock{DAResult: da.DAResult{Code: da.StatusError, Message: err.Error()}}
+	blocks := make([]*types.Block, len(resp.Blocks))
+	for i, block := range resp.Blocks {
+		var b types.Block
+		err = b.FromProto(block)
+		if err != nil {
+			return da.ResultRetrieveBlocks{DAResult: da.DAResult{Code: da.StatusError, Message: err.Error()}}
+		}
+		blocks[i] = &b
 	}
-	return da.ResultRetrieveBlock{
-		DAResult: da.DAResult{Code: da.StatusCode(resp.Result.Code), Message: resp.Result.Message},
-		Block:    &b,
+	return da.ResultRetrieveBlocks{
+		DAResult: da.DAResult{
+			Code:     da.StatusCode(resp.Result.Code),
+			Message:  resp.Result.Message,
+			DAHeight: dataLayerHeight,
+		},
+		Blocks: blocks,
 	}
 }

da/grpc/mockserv/cmd/main.go

@@ -24,7 +24,7 @@ func main() {
 		log.Panic(err)
 	}
 	log.Println("Listening on:", lis.Addr())
-	srv := mockserv.GetServer(kv, conf)
+	srv := mockserv.GetServer(kv, conf, nil)
 	if err := srv.Serve(lis); err != nil {
 		log.Println("error while serving:", err)
 	}