path: root/core/interfaces.go

// Copyright 2018 The dexon-consensus-core Authors
// This file is part of the dexon-consensus-core library.
//
// The dexon-consensus-core library is free software: you can redistribute it
// and/or modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation, either version 3 of the License,
// or (at your option) any later version.
//
// The dexon-consensus-core library is distributed in the hope that it will be
// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
// General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the dexon-consensus-core library. If not, see
// <http://www.gnu.org/licenses/>.

package core

import (
    "time"

    "github.com/dexon-foundation/dexon-consensus-core/common"
    "github.com/dexon-foundation/dexon-consensus-core/core/types"
    "github.com/dexon-foundation/dexon-consensus-core/crypto"
)

// Application describes the application interface that interacts with DEXON
// consensus core.
type Application interface {
    // PreparePayload is called when consensus core is preparing a block.
    PreparePayload(position types.Position) []byte

    // VerifyPayload verifies if the payload is valid.
    VerifyPayload(payload []byte) bool

    // BlockDelivered is called when a block is add to the compaction chain.
    BlockDelivered(block types.Block)

    // BlockProcessedChan returns a channel to receive the block hashes that have
    // finished processing by the application.
    BlockProcessedChan() <-chan types.WitnessResult

    // WitnessAckDelivered is called when a witness ack is created.
    WitnessAckDelivered(witnessAck *types.WitnessAck)
}

// Debug describes the application interface that requires
// more detailed consensus execution.
type Debug interface {
    // BlockConfirmed is called when a block is confirmed and added to lattice.
    BlockConfirmed(blockHash common.Hash)

    // StronglyAcked is called when a block is strongly acked.
    StronglyAcked(blockHash common.Hash)

    // TotalOrderingDelivered is called when the total ordering algorithm deliver
    // a set of block.
    TotalOrderingDelivered(blockHashes common.Hashes, early bool)
}

// Network describs the network interface that interacts with DEXON consensus
// core.
type Network interface {
    // BroadcastVote broadcasts vote to all nodes in DEXON network.
    BroadcastVote(vote *types.Vote)

    // BroadcastBlock broadcasts block to all nodes in DEXON network.
    BroadcastBlock(block *types.Block)

    // BroadcastWitnessAck broadcasts witnessAck to all nodes in DEXON network.
    BroadcastWitnessAck(witnessAck *types.WitnessAck)

    // SendDKGPrivateShare sends PrivateShare to a DKG participant.
    SendDKGPrivateShare(recv types.NodeID, prvShare *types.DKGPrivateShare)

    // BroadcastDKGPrivateShare broadcasts PrivateShare to all DKG participants.
    BroadcastDKGPrivateShare(prvShare *types.DKGPrivateShare)

    // BroadcastDKGPartialSignature broadcasts partialSignature to all
    // DKG participants.
    BroadcastDKGPartialSignature(psig *types.DKGPartialSignature)

    // ReceiveChan returns a channel to receive messages from DEXON network.
    ReceiveChan() <-chan interface{}
}

// Governance interface specifies interface to control the governance contract.
// Note that there are a lot more methods in the governance contract, that this
// interface only define those that are required to run the consensus algorithm.
type Governance interface {
    // GetConfiguration returns the configuration at a given block height.
    // Return the genesis configuration if blockHeight == 0.
    GetConfiguration(blockHeight uint64) *types.Config

    // Get the current notary set.
    // Return the genesis notary set if blockHeight == 0.
    GetNotarySet(blockHeight uint64) map[types.NodeID]struct{}

    // Porpose a ThresholdSignature of round.
    ProposeThresholdSignature(round uint64, signature crypto.Signature)

    // Get a ThresholdSignature of round.
    GetThresholdSignature(round uint64) (sig crypto.Signature, exist bool)

    //// DKG-related methods.

    // AddDKGComplaint adds a DKGComplaint.
    AddDKGComplaint(complaint *types.DKGComplaint)

    // GetDKGComplaints gets all the DKGComplaints of round.
    DKGComplaints(round uint64) []*types.DKGComplaint

    // AddDKGMasterPublicKey adds a DKGMasterPublicKey.
    AddDKGMasterPublicKey(masterPublicKey *types.DKGMasterPublicKey)

    // DKGMasterPublicKeys gets all the DKGMasterPublicKey of round.
    DKGMasterPublicKeys(round uint64) []*types.DKGMasterPublicKey
}

// Ticker define the capability to tick by interval.
type Ticker interface {
    // Tick would return a channel, which would be triggered until next tick.
    Tick() <-chan time.Time

    // Stop the ticker.
    Stop()
}

// Signer defines a role to sign data.
type Signer interface {
    // SignBlock signs a block.
    SignBlock(b *types.Block) error

    // SignVote signs a vote.
    SignVote(v *types.Vote) error

    // SignCRS sign a block's CRS signature.
    SignCRS(b *types.Block, crs common.Hash) error
}

// CryptoVerifier defines a role to verify data in crypto's way.
type CryptoVerifier interface {
    // VerifyBlock verifies if a block is properly signed or not.
    VerifyBlock(b *types.Block) (ok bool, err error)

    // VerifyVote verfies if a vote is properly signed or not.
    VerifyVote(v *types.Vote) (ok bool, err error)

    // VerifyCRS verifies if a CRS signature of one block is valid or not.
    VerifyCRS(b *types.Block, crs common.Hash) (ok bool, err error)
}

// Authenticator verify/sign who own the data.
type Authenticator interface {
    Signer
    CryptoVerifier
}