Merge pull request #73 from filecoin-project/feat/persist-chain-head

store and load latest chain head in the datastore

chain/chain.go

@@ -24,6 +24,8 @@ const ForkLengthThreshold = 20
 
 var log = logging.Logger("f2")
 
+var chainHeadKey = dstore.NewKey("head")
+
 type GenesisBootstrap struct {
 	Genesis  *BlockHeader
 	MinerKey address.Address
@@ -232,6 +234,44 @@ func NewChainStore(bs bstore.Blockstore, ds dstore.Batching) *ChainStore {
 	}
 }
 
+func (cs *ChainStore) Load() error {
+	head, err := cs.ds.Get(chainHeadKey)
+	if err == dstore.ErrNotFound {
+		log.Warn("no previous chain state found")
+		return nil
+	}
+	if err != nil {
+		return errors.Wrap(err, "failed to load chain state from datastore")
+	}
+
+	var tscids []cid.Cid
+	if err := json.Unmarshal(head, &tscids); err != nil {
+		return errors.Wrap(err, "failed to unmarshal stored chain head")
+	}
+
+	ts, err := cs.LoadTipSet(tscids)
+	if err != nil {
+		return err
+	}
+
+	cs.heaviest = ts
+
+	return nil
+}
+
+func (cs *ChainStore) writeHead(ts *TipSet) error {
+	data, err := json.Marshal(ts.Cids())
+	if err != nil {
+		return errors.Wrap(err, "failed to marshal tipset")
+	}
+
+	if err := cs.ds.Put(chainHeadKey, data); err != nil {
+		return errors.Wrap(err, "failed to write chain head to datastore")
+	}
+
+	return nil
+}
+
 func (cs *ChainStore) SubNewTips() chan *TipSet {
 	subch := cs.bestTips.Sub("best")
 	out := make(chan *TipSet)
@@ -315,6 +355,11 @@ func (cs *ChainStore) maybeTakeHeavierTipSet(ts *TipSet) error {
 		}
 		log.Infof("New heaviest tipset! %s", ts.Cids())
 		cs.heaviest = ts
+
+		if err := cs.writeHead(ts); err != nil {
+			log.Errorf("failed to write chain head: %s", err)
+			return nil
+		}
 	}
 	return nil
 }

miner/miner.go

@@ -39,6 +39,7 @@ type api interface {
 func NewMiner(api api, addr address.Address) *Miner {
 	return &Miner{
 		api:     api,
+		address: addr,
 		Delay:   time.Second * 4,
 	}
 }

node/builder.go

@@ -128,6 +128,9 @@ func defaults() []Option {
 	return []Option{
 		Override(new(helpers.MetricsCtx), context.Background),
 		Override(new(record.Validator), modules.RecordValidator),
+
+		// Filecoin modules
+
 	}
 }
 
@@ -180,7 +183,7 @@ func Online() Option {
 
 			Override(HandleIncomingMessagesKey, modules.HandleIncomingMessages),
 
-			Override(new(*chain.ChainStore), chain.NewChainStore),
+			Override(new(*chain.ChainStore), modules.ChainStore),
 
 			Override(new(blockstore.GCLocker), blockstore.NewGCLocker),
 			Override(new(blockstore.GCBlockstore), blockstore.NewGCBlockstore),

node/modules/core.go

@@ -8,6 +8,7 @@ import (
 	"path/filepath"
 
 	"github.com/gbrlsnchs/jwt/v3"
+
 	"github.com/ipfs/go-bitswap"
 	"github.com/ipfs/go-bitswap/network"
 	"github.com/ipfs/go-blockservice"
@@ -163,3 +164,15 @@ func ClientDAG(lc fx.Lifecycle, fstore *filestore.Filestore) ipld.DAGService {
 
 	return dag
 }
+
+func ChainStore(lc fx.Lifecycle, bs blockstore.Blockstore, ds datastore.Batching) *chain.ChainStore {
+	chain := chain.NewChainStore(bs, ds)
+
+	lc.Append(fx.Hook{
+		OnStart: func(ctx context.Context) error {
+			return chain.Load()
+		},
+	})
+
+	return chain
+}