Merge pull request #2979 from karalabe/ethclient-sync-api

ethereum, ethclient: add SyncProgress API endpoint

eth/downloader/api.go

@@ -19,6 +19,7 @@ package downloader
 import (
 	"sync"
 
+	ethereum "github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/rpc"
 	"golang.org/x/net/context"
@@ -73,9 +74,10 @@ func (api *PublicDownloaderAPI) eventLoop() {
 			var notification interface{}
 			switch event.Data.(type) {
 			case StartEvent:
-				result := &SyncingResult{Syncing: true}
-				result.Status.Origin, result.Status.Current, result.Status.Height, result.Status.Pulled, result.Status.Known = api.d.Progress()
-				notification = result
+				notification = &SyncingResult{
+					Syncing: true,
+					Status:  api.d.Progress(),
+				}
 			case DoneEvent, FailedEvent:
 				notification = false
 			}
@@ -117,19 +119,10 @@ func (api *PublicDownloaderAPI) Syncing(ctx context.Context) (*rpc.Subscription,
 	return rpcSub, nil
 }
 
-// Progress gives progress indications when the node is synchronising with the Ethereum network.
-type Progress struct {
-	Origin  uint64 `json:"startingBlock"`
-	Current uint64 `json:"currentBlock"`
-	Height  uint64 `json:"highestBlock"`
-	Pulled  uint64 `json:"pulledStates"`
-	Known   uint64 `json:"knownStates"`
-}
-
 // SyncingResult provides information about the current synchronisation status for this node.
 type SyncingResult struct {
-	Syncing bool     `json:"syncing"`
-	Status  Progress `json:"status"`
+	Syncing bool                  `json:"syncing"`
+	Status  ethereum.SyncProgress `json:"status"`
 }
 
 // uninstallSyncSubscriptionRequest uninstalles a syncing subscription in the API event loop.

eth/downloader/downloader.go

@@ -28,6 +28,7 @@ import (
 	"sync/atomic"
 	"time"
 
+	ethereum "github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/ethdb"
@@ -211,7 +212,7 @@ func New(stateDb ethdb.Database, mux *event.TypeMux, hasHeader headerCheckFn, ha
 // In addition, during the state download phase of fast synchronisation the number
 // of processed and the total number of known states are also returned. Otherwise
 // these are zero.
-func (d *Downloader) Progress() (uint64, uint64, uint64, uint64, uint64) {
+func (d *Downloader) Progress() ethereum.SyncProgress {
 	// Fetch the pending state count outside of the lock to prevent unforeseen deadlocks
 	pendingStates := uint64(d.queue.PendingNodeData())
 
@@ -228,7 +229,13 @@ func (d *Downloader) Progress() (uint64, uint64, uint64, uint64, uint64) {
 	case LightSync:
 		current = d.headHeader().Number.Uint64()
 	}
-	return d.syncStatsChainOrigin, current, d.syncStatsChainHeight, d.syncStatsStateDone, d.syncStatsStateDone + pendingStates
+	return ethereum.SyncProgress{
+		StartingBlock: d.syncStatsChainOrigin,
+		CurrentBlock:  current,
+		HighestBlock:  d.syncStatsChainHeight,
+		PulledStates:  d.syncStatsStateDone,
+		KnownStates:   d.syncStatsStateDone + pendingStates,
+	}
 }
 
 // Synchronising returns whether the downloader is currently retrieving blocks.

ethclient/ethclient.go

@@ -191,6 +191,39 @@ func toBlockNumArg(number *big.Int) string {
 	return fmt.Sprintf("%#x", number)
 }
 
+type rpcProgress struct {
+	StartingBlock rpc.HexNumber
+	CurrentBlock  rpc.HexNumber
+	HighestBlock  rpc.HexNumber
+	PulledStates  rpc.HexNumber
+	KnownStates   rpc.HexNumber
+}
+
+// SyncProgress retrieves the current progress of the sync algorithm. If there's
+// no sync currently running, it returns nil.
+func (ec *Client) SyncProgress(ctx context.Context) (*ethereum.SyncProgress, error) {
+	var raw json.RawMessage
+	if err := ec.c.CallContext(ctx, &raw, "eth_syncing"); err != nil {
+		return nil, err
+	}
+	// Handle the possible response types
+	var syncing bool
+	if err := json.Unmarshal(raw, &syncing); err == nil {
+		return nil, nil // Not syncing (always false)
+	}
+	var progress *rpcProgress
+	if err := json.Unmarshal(raw, &progress); err != nil {
+		return nil, err
+	}
+	return &ethereum.SyncProgress{
+		StartingBlock: progress.StartingBlock.Uint64(),
+		CurrentBlock:  progress.CurrentBlock.Uint64(),
+		HighestBlock:  progress.HighestBlock.Uint64(),
+		PulledStates:  progress.PulledStates.Uint64(),
+		KnownStates:   progress.KnownStates.Uint64(),
+	}, nil
+}
+
 // SubscribeNewHead subscribes to notifications about the current blockchain head
 // on the given channel.
 func (ec *Client) SubscribeNewHead(ctx context.Context, ch chan<- *types.Header) (ethereum.Subscription, error) {

ethclient/ethclient_test.go

@@ -6,6 +6,7 @@ import "github.com/ethereum/go-ethereum"
 var (
 	_ = ethereum.ChainReader(&Client{})
 	_ = ethereum.ChainStateReader(&Client{})
+	_ = ethereum.ChainSyncReader(&Client{})
 	_ = ethereum.ChainHeadEventer(&Client{})
 	_ = ethereum.ContractCaller(&Client{})
 	_ = ethereum.GasEstimator(&Client{})

interfaces.go

@@ -67,6 +67,22 @@ type ChainStateReader interface {
 	NonceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (uint64, error)
 }
 
+// SyncProgress gives progress indications when the node is synchronising with
+// the Ethereum network.
+type SyncProgress struct {
+	StartingBlock uint64 // Block number where sync began
+	CurrentBlock  uint64 // Current block number where sync is at
+	HighestBlock  uint64 // Highest alleged block number in the chain
+	PulledStates  uint64 // Number of state trie entries already downloaded
+	KnownStates   uint64 // Total number os state trie entries known about
+}
+
+// ChainSyncReader wraps access to the node's current sync status. If there's no
+// sync currently running, it returns nil.
+type ChainSyncReader interface {
+	SyncProgress(ctx context.Context) (*SyncProgress, error)
+}
+
 // A ChainHeadEventer returns notifications whenever the canonical head block is updated.
 type ChainHeadEventer interface {
 	SubscribeNewHead(ctx context.Context, ch chan<- *types.Header) (Subscription, error)

internal/ethapi/api.go

@@ -73,19 +73,19 @@ func (s *PublicEthereumAPI) ProtocolVersion() *rpc.HexNumber {
 // - pulledStates:  number of state entries processed until now
 // - knownStates:   number of known state entries that still need to be pulled
 func (s *PublicEthereumAPI) Syncing() (interface{}, error) {
-	origin, current, height, pulled, known := s.b.Downloader().Progress()
+	progress := s.b.Downloader().Progress()
 
 	// Return not syncing if the synchronisation already completed
-	if current >= height {
+	if progress.CurrentBlock >= progress.HighestBlock {
 		return false, nil
 	}
 	// Otherwise gather the block sync stats
 	return map[string]interface{}{
-		"startingBlock": rpc.NewHexNumber(origin),
-		"currentBlock":  rpc.NewHexNumber(current),
-		"highestBlock":  rpc.NewHexNumber(height),
-		"pulledStates":  rpc.NewHexNumber(pulled),
-		"knownStates":   rpc.NewHexNumber(known),
+		"startingBlock": rpc.NewHexNumber(progress.StartingBlock),
+		"currentBlock":  rpc.NewHexNumber(progress.CurrentBlock),
+		"highestBlock":  rpc.NewHexNumber(progress.HighestBlock),
+		"pulledStates":  rpc.NewHexNumber(progress.PulledStates),
+		"knownStates":   rpc.NewHexNumber(progress.KnownStates),
 	}, nil
 }