eth/internal: add debug.peerStats for stats related to all connected peers (#1252)

* implement debug.peerStats for stats related to all connected peers

* add identifier for ipc

* display block number in peer stats

* eth/downloader: log error while terminating sync

eth/api_backend.go

@@ -474,3 +474,7 @@ func (b *EthAPIBackend) GetWhitelistedMilestone() (bool, uint64, common.Hash) {
 func (b *EthAPIBackend) PurgeWhitelistedMilestone() {
 	b.eth.Downloader().ChainValidator.PurgeWhitelistedMilestone()
 }
+
+func (b *EthAPIBackend) PeerStats() interface{} {
+	return b.eth.handler.GetPeerStats()
+}

eth/downloader/downloader.go

@@ -512,7 +512,7 @@ func (d *Downloader) syncWithPeer(p *peerConnection, hash common.Hash, td, ttd *
 	}
 
 	defer func(start time.Time) {
-		log.Debug("Synchronisation terminated", "elapsed", common.PrettyDuration(time.Since(start)))
+		log.Debug("Synchronisation terminated", "elapsed", common.PrettyDuration(time.Since(start)), "err", err)
 	}(time.Now())
 
 	// Look up the sync boundaries: the common ancestor and the target block

eth/handler.go

@@ -728,3 +728,40 @@ func (h *handler) enableSyncedFeatures() {
 		h.chain.TrieDB().SetBufferSize(pathdb.DefaultBufferSize)
 	}
 }
+
+// PeerStats represents a short summary of the information known about a connected
+// peer. Specifically, it contains details about the head hash and total difficulty
+// of a peer which makes it a bit different from the PeerInfo.
+type PeerStats struct {
+	Enode  string `json:"enode"`  // Node URL
+	ID     string `json:"id"`     // Unique node identifier
+	Name   string `json:"name"`   // Name of the node, including client type, version, OS, custom data
+	Hash   string `json:"hash"`   // Head hash of the peer
+	Number uint64 `json:"number"` // Head number of the peer
+	Td     uint64 `json:"td"`     // Total difficulty of the peer
+}
+
+// PeerStats returns the current head height and td of all the connected peers
+// along with few additional identifiers.
+func (h *handler) GetPeerStats() []*PeerStats {
+	info := make([]*PeerStats, 0, len(h.peers.peers))
+
+	for _, peer := range h.peers.peers {
+		hash, td := peer.Head()
+		block := h.chain.GetBlockByHash(hash)
+		number := uint64(0)
+		if block != nil {
+			number = block.NumberU64()
+		}
+		info = append(info, &PeerStats{
+			Enode:  peer.Node().URLv4(),
+			ID:     peer.ID(),
+			Name:   peer.Name(),
+			Hash:   hash.String(),
+			Number: number,
+			Td:     td.Uint64(),
+		})
+	}
+
+	return info
+}

internal/ethapi/api.go

@@ -2729,6 +2729,12 @@ func (api *DebugAPI) GetTraceStack() string {
 	}
 }
 
+// PeerStats returns the current head height and td of all the connected peers
+// along with few additional identifiers.
+func (api *DebugAPI) PeerStats() interface{} {
+	return api.b.PeerStats()
+}
+
 // NetAPI offers network related RPC methods
 type NetAPI struct {
 	net            *p2p.Server

internal/ethapi/api_test.go

@@ -644,6 +644,10 @@ func (b testBackend) SubscribeStateSyncEvent(ch chan<- core.StateSyncEvent) even
 	panic("implement me")
 }
 
+func (b testBackend) PeerStats() interface{} {
+	panic("implement me")
+}
+
 func (b testBackend) GetBorBlockLogs(ctx context.Context, hash common.Hash) ([]*types.Log, error) {
 	receipt, err := b.GetBorBlockReceipt(ctx, hash)
 	if err != nil || receipt == nil {

internal/ethapi/backend.go

@@ -112,6 +112,9 @@ type Backend interface {
 	PurgeWhitelistedCheckpoint()
 	GetWhitelistedMilestone() (bool, uint64, common.Hash)
 	PurgeWhitelistedMilestone()
+
+	// Networking related APIs
+	PeerStats() interface{}
 }
 
 func GetAPIs(apiBackend Backend) []rpc.API {

internal/ethapi/transaction_args_test.go

@@ -412,3 +412,7 @@ func (b *backendMock) GetWhitelistedMilestone() (bool, uint64, common.Hash) {
 func (b *backendMock) PurgeWhitelistedCheckpoint() {}
 
 func (b *backendMock) PurgeWhitelistedMilestone() {}
+
+func (b backendMock) PeerStats() interface{} {
+	return nil
+}

internal/web3ext/web3ext.go

@@ -565,6 +565,11 @@ web3._extend({
 			call: 'debug_getTrieFlushInterval',
 			params: 0
 		}),
+		new web3._extend.Method({
+			name: 'peerStats',
+			call: 'debug_peerStats',
+			params: 0
+		}),
 	],
 	properties: []
 });

les/api_backend.go

@@ -376,3 +376,7 @@ func (b *LesApiBackend) GetWhitelistedMilestone() (bool, uint64, common.Hash) {
 
 func (b *LesApiBackend) PurgeWhitelistedMilestone() {
 }
+
+func (b *LesApiBackend) PeerStats() interface{} {
+	return nil
+}