[Uptime] Compute and return lastest 30 epoch signing information (#3249)

* [Uptime] Compute and return lastest 30 epoch signing information

* subtract previous epoch counters

* caching properly for each validator

hmy/staking.go

@@ -199,6 +199,52 @@ func (hmy *Harmony) GetAllValidatorAddresses() []common.Address {
 	return hmy.BlockChain.ValidatorCandidates()
 }
 
+var (
+	epochBlocksMap = map[common.Address]map[uint64]staking.EpochSigningEntry{}
+)
+
+func (hmy *Harmony) getEpochSigning(epoch *big.Int, addr common.Address) (staking.EpochSigningEntry, error) {
+	entry := staking.EpochSigningEntry{}
+	if validatorMap, ok := epochBlocksMap[addr]; ok {
+		if val, ok := validatorMap[epoch.Uint64()]; ok {
+			return val, nil
+		}
+	}
+
+	snapshot, err := hmy.BlockChain.ReadValidatorSnapshotAtEpoch(epoch, addr)
+	if err != nil {
+		return entry, err
+	}
+
+	// the signing information is for the previous epoch
+	prevEpoch := big.NewInt(0).Sub(epoch, common.Big1)
+	entry.Epoch = prevEpoch
+	entry.Blocks = snapshot.Validator.Counters
+
+	// subtract previous epoch counters if exists
+	prevEpochSnap, err := hmy.BlockChain.ReadValidatorSnapshotAtEpoch(prevEpoch, addr)
+	if err == nil {
+		entry.Blocks.NumBlocksSigned.Sub(
+			entry.Blocks.NumBlocksSigned,
+			prevEpochSnap.Validator.Counters.NumBlocksSigned,
+		)
+		entry.Blocks.NumBlocksToSign.Sub(
+			entry.Blocks.NumBlocksToSign,
+			prevEpochSnap.Validator.Counters.NumBlocksToSign,
+		)
+	}
+
+	// update map when adding new entry, also remove an entry beyond last 30
+	if _, ok := epochBlocksMap[addr]; !ok {
+		epochBlocksMap[addr] = map[uint64]staking.EpochSigningEntry{}
+	}
+	epochBlocksMap[addr][epoch.Uint64()] = entry
+	epochMinus30 := big.NewInt(0).Sub(epoch, big.NewInt(staking.SigningHistoryLength))
+	delete(epochBlocksMap[addr], epochMinus30.Uint64())
+
+	return entry, nil
+}
+
 // GetValidatorInformation returns the information of validator
 func (hmy *Harmony) GetValidatorInformation(
 	addr common.Address, block *types.Block,
@@ -320,6 +366,22 @@ func (hmy *Harmony) GetValidatorInformation(
 	// 	defaultReply.Lifetime.APR = avgAPR.(numeric.Dec)
 	// }
 
+	epochBlocks := []staking.EpochSigningEntry{}
+	epochFrom := bc.Config().StakingEpoch
+	nowMinus := big.NewInt(0).Sub(now, big.NewInt(staking.SigningHistoryLength))
+	if nowMinus.Cmp(epochFrom) > 0 {
+		epochFrom = nowMinus
+	}
+	for i := now.Int64(); i > epochFrom.Int64(); i-- {
+		epoch := big.NewInt(i)
+		entry, err := hmy.getEpochSigning(epoch, addr)
+		if err != nil {
+			break
+		}
+		epochBlocks = append(epochBlocks, entry)
+	}
+	defaultReply.Lifetime.EpochBlocks = epochBlocks
+
 	if defaultReply.CurrentlyInCommittee {
 		defaultReply.ComputedMetrics = stats
 		defaultReply.EPoSWinningStake = &stats.TotalEffectiveStake

staking/types/validator.go

@@ -30,6 +30,7 @@ const (
 	BLSVerificationStr       = "harmony-one"
 	TenThousand              = 10000
 	APRHistoryLength         = 30
+	SigningHistoryLength     = 30
 )
 
 var (
@@ -156,10 +157,11 @@ type ValidatorRPCEnhanced struct {
 
 // AccumulatedOverLifetime ..
 type AccumulatedOverLifetime struct {
-	BlockReward *big.Int    `json:"reward-accumulated"`
-	Signing     counters    `json:"blocks"`
-	APR         numeric.Dec `json:"apr"`
-	EpochAPRs   []APREntry  `json:"epoch-apr"`
+	BlockReward *big.Int            `json:"reward-accumulated"`
+	Signing     counters            `json:"blocks"`
+	APR         numeric.Dec         `json:"apr"`
+	EpochAPRs   []APREntry          `json:"epoch-apr"`
+	EpochBlocks []EpochSigningEntry `json:"epoch-blocks"`
 }
 
 func (w ValidatorWrapper) String() string {
@@ -188,8 +190,14 @@ type VoteWithCurrentEpochEarning struct {
 
 // APREntry ..
 type APREntry struct {
-	Epoch *big.Int
-	Value numeric.Dec
+	Epoch *big.Int    `json:"epoch"`
+	Value numeric.Dec `json:"apr"`
+}
+
+// EpochSigningEntry ..
+type EpochSigningEntry struct {
+	Epoch  *big.Int `json:"epoch"`
+	Blocks counters `json:"blocks"`
 }
 
 // ValidatorStats to record validator's performance and history records