Merge pull request #585 from keep-network/redemption-actions

Redemption flow actions

Expands the TBTC extension by adding two new actions specific to the deposit redemption flow.

ProvideRedemptionSignature action
- Starts the monitoring on new RedemptionRequested event. That event is emitted 
either by requestRedemption or increaseRedemptionFee contract methods.
- Stops the monitoring if GotRedemptionSignature or Redeemed event occurs for the 
observed deposit. This means either provideRedemptionSignature or provideRedemptionProof 
has been called by someone else.
- Performs the provideRedemptionSignature action once the deposit is close to exceeding the 
redemption signature timeout.

ProvideRedemptionProof action
- Starts the monitoring on new GotRedemptionSignature event. This event occurs once 
provideRedemptionSignature contract method is called.
- Stops the monitoring if RedemptionRequested or Redeemed event occurs for the observed 
deposit. These events can be emitted by increaseRedemptionFee or provideRedemptionProof 
respectively.
- Performs the increaseRedemptionFee action once the deposit is close to exceeding the
redemption proof timeout. This part will be extended soon by adding the ability of submitting
the redemption proof directy if the BTC transaction exists.

go.mod

@@ -20,7 +20,7 @@ require (
 	github.com/ipfs/go-log v1.0.4
 	github.com/keep-network/keep-common v1.2.1-0.20201020114759-19c123cbd4f4
 	github.com/keep-network/keep-core v1.3.0
-	github.com/keep-network/tbtc v1.1.1-0.20201020115551-5f9077c74826
+	github.com/keep-network/tbtc v1.1.1-0.20201026093513-cb9246987718
 	github.com/pkg/errors v0.9.1
 	github.com/urfave/cli v1.22.1
 )

go.sum

@@ -337,8 +337,8 @@ github.com/keep-network/keep-common v1.2.1-0.20201020114759-19c123cbd4f4 h1:Civu
 github.com/keep-network/keep-common v1.2.1-0.20201020114759-19c123cbd4f4/go.mod h1:emxogTbBdey7M3jOzfxZOdfn139kN2mI2b2wA6AHKKo=
 github.com/keep-network/keep-core v1.3.0 h1:7Tb33EmO/ntHOEbOiYciRlBhqu5Ln6KemWCaYK0Z6LA=
 github.com/keep-network/keep-core v1.3.0/go.mod h1:1KsSSTQoN754TrFLW7kLy50pOG2CQ4BOfnJqdvEG7FA=
-github.com/keep-network/tbtc v1.1.1-0.20201020115551-5f9077c74826 h1:ijlpSs+mEtur4F1DQA8450Ubuhdk4lGjIoPZr3yf7vc=
-github.com/keep-network/tbtc v1.1.1-0.20201020115551-5f9077c74826/go.mod h1:igBF2MPTFkzOdZ3gcwt8h0Zb5pZaHnij/iPZoMB9IKM=
+github.com/keep-network/tbtc v1.1.1-0.20201026093513-cb9246987718 h1:/ZNMBY7y6hfzCYA8mgtHnspGO26OmWV3sDehyGnqRyY=
+github.com/keep-network/tbtc v1.1.1-0.20201026093513-cb9246987718/go.mod h1:igBF2MPTFkzOdZ3gcwt8h0Zb5pZaHnij/iPZoMB9IKM=
 github.com/keep-network/toml v0.3.0 h1:G+NJwWR/ZiORqeLBsDXDchYoL29PXHdxOPcCueA7ctE=
 github.com/keep-network/toml v0.3.0/go.mod h1:Zeyd3lxbIlMYLREho3UK1dMP2xjqt2gLkQ5E5vM6K38=
 github.com/kisielk/errcheck v1.1.0/go.mod h1:EZBBE59ingxPouuu3KfxchcWSUPOHkagtvWXihfKN4Q=

pkg/chain/chain.go

@@ -20,6 +20,9 @@ type Handle interface {
 	StakeMonitor() (chain.StakeMonitor, error)
 	// BlockCounter returns a block counter.
 	BlockCounter() chain.BlockCounter
+	// BlockTimestamp returns given block's timestamp.
+	// In case the block is not yet mined, an error should be returned.
+	BlockTimestamp(blockNumber *big.Int) (uint64, error)
 
 	BondedECDSAKeepFactory
 	BondedECDSAKeep
@@ -143,4 +146,13 @@ type BondedECDSAKeep interface {
 
 	// GetOpenedTimestamp returns timestamp when the keep was created.
 	GetOpenedTimestamp(keepAddress common.Address) (time.Time, error)
+
+	// PastSignatureSubmittedEvents returns all signature submitted events
+	// for the given keep which occurred after the provided start block.
+	// All implementations should returns those events sorted by the
+	// block number in the ascending order.
+	PastSignatureSubmittedEvents(
+		keepAddress string,
+		startBlock uint64,
+	) ([]*SignatureSubmittedEvent, error)
 }

pkg/chain/ethereum/connect.go

@@ -1,6 +1,7 @@
 package ethereum
 
 import (
+	"context"
 	"fmt"
 	"math/big"
 	"sync"
@@ -41,6 +42,7 @@ type EthereumChain struct {
 	blockCounter                   *blockcounter.EthereumBlockCounter
 	miningWaiter                   *ethutil.MiningWaiter
 	nonceManager                   *ethutil.NonceManager
+	blockTimestampFn               blockTimestampFn
 
 	// transactionMutex allows interested parties to forcibly serialize
 	// transaction submission.
@@ -65,6 +67,10 @@ func Connect(accountKey *keystore.Key, config *ethereum.Config) (*EthereumChain,
 		return nil, err
 	}
 
+	// TODO: Add rate limiting to (keep-ecdsa/pull/585#discussion_r513351032):
+	//  - `createBlockTimestampFn`
+	//  - `blockCounter`
+	//  - `miningWaiter`
 	wrappedClient := addClientWrappers(config, client)
 
 	transactionMutex := &sync.Mutex{}
@@ -120,6 +126,7 @@ func Connect(accountKey *keystore.Key, config *ethereum.Config) (*EthereumChain,
 		nonceManager:                   nonceManager,
 		miningWaiter:                   miningWaiter,
 		transactionMutex:               transactionMutex,
+		blockTimestampFn:               createBlockTimestampFn(client),
 	}, nil
 }
 
@@ -149,3 +156,19 @@ func addClientWrappers(
 
 	return loggingBackend
 }
+
+type blockTimestampFn func(blockNumber *big.Int) (uint64, error)
+
+func createBlockTimestampFn(client *ethclient.Client) blockTimestampFn {
+	return func(blockNumber *big.Int) (uint64, error) {
+		ctx, cancelCtx := context.WithTimeout(context.Background(), 1*time.Minute)
+		defer cancelCtx()
+
+		header, err := client.HeaderByNumber(ctx, blockNumber)
+		if err != nil {
+			return 0, err
+		}
+
+		return header.Time, nil
+	}
+}

pkg/chain/ethereum/ethereum.go

@@ -4,8 +4,11 @@ package ethereum
 import (
 	"fmt"
 	"math/big"
+	"sort"
 	"time"
 
+	"github.com/keep-network/keep-ecdsa/pkg/chain/gen/eventlog"
+
 	"github.com/ethereum/go-ethereum/common"
 
 	"github.com/ipfs/go-log"
@@ -507,3 +510,55 @@ func (ec *EthereumChain) GetOpenedTimestamp(keepAddress common.Address) (time.Ti
 
 	return keepOpenTime, nil
 }
+
+// PastSignatureSubmittedEvents returns all signature submitted events
+// for the given keep which occurred after the provided start block.
+// Returned events are sorted by the block number in the ascending order.
+func (ec *EthereumChain) PastSignatureSubmittedEvents(
+	keepAddress string,
+	startBlock uint64,
+) ([]*eth.SignatureSubmittedEvent, error) {
+	if !common.IsHexAddress(keepAddress) {
+		return nil, fmt.Errorf("invalid keep address: [%v]", keepAddress)
+	}
+
+	keepContractEventLog, err := eventlog.NewBondedECDSAKeepEventLog(
+		common.HexToAddress(keepAddress),
+		ec.client,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	events, err := keepContractEventLog.PastSignatureSubmittedEvents(
+		startBlock,
+		nil,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	result := make([]*eth.SignatureSubmittedEvent, 0)
+
+	for _, event := range events {
+		result = append(result, &eth.SignatureSubmittedEvent{
+			Digest:      event.Digest,
+			R:           event.R,
+			S:           event.S,
+			RecoveryID:  event.RecoveryID,
+			BlockNumber: event.BlockNumber,
+		})
+	}
+
+	// Make sure events are sorted by block number in ascending order.
+	sort.SliceStable(result, func(i, j int) bool {
+		return result[i].BlockNumber < result[j].BlockNumber
+	})
+
+	return result, nil
+}
+
+// BlockTimestamp returns given block's timestamp.
+func (ec *EthereumChain) BlockTimestamp(blockNumber *big.Int) (uint64, error) {
+	return ec.blockTimestampFn(blockNumber)
+}