Add ommitted consensus package

restricted/consensus/consensus.go

@@ -0,0 +1,102 @@
+package consensus
+
+import (
+	"math/big"
+	"github.com/openrelayxyz/plugeth-utils/restricted/params"
+	"github.com/openrelayxyz/plugeth-utils/restricted/types"
+	"github.com/openrelayxyz/plugeth-utils/core"
+)
+
+// ChainHeaderReader defines a small collection of methods needed to access the local
+// blockchain during header verification.
+type ChainHeaderReader interface {
+	// Config retrieves the blockchain's chain configuration.
+	Config() *params.ChainConfig
+
+	// CurrentHeader retrieves the current header from the local chain.
+	CurrentHeader() *types.Header
+
+	// GetHeader retrieves a block header from the database by hash and number.
+	GetHeader(hash core.Hash, number uint64) *types.Header
+
+	// GetHeaderByNumber retrieves a block header from the database by number.
+	GetHeaderByNumber(number uint64) *types.Header
+
+	// GetHeaderByHash retrieves a block header from the database by its hash.
+	GetHeaderByHash(hash core.Hash) *types.Header
+
+	// GetTd retrieves the total difficulty from the database by hash and number.
+	GetTd(hash core.Hash, number uint64) *big.Int
+}
+
+// ChainReader defines a small collection of methods needed to access the local
+// blockchain during header and/or uncle verification.
+type ChainReader interface {
+	ChainHeaderReader
+
+	// GetBlock retrieves a block from the database by hash and number.
+	GetBlock(hash core.Hash, number uint64) *types.Block
+}
+
+// Engine is an algorithm agnostic consensus engine.
+type Engine interface {
+	// Author retrieves the Ethereum address of the account that minted the given
+	// block, which may be different from the header's coinbase if a consensus
+	// engine is based on signatures.
+	Author(header *types.Header) (core.Address, error)
+
+	// VerifyHeader checks whether a header conforms to the consensus rules of a
+	// given engine. Verifying the seal may be done optionally here, or explicitly
+	// via the VerifySeal method.
+	VerifyHeader(chain ChainHeaderReader, header *types.Header, seal bool) error
+
+	// VerifyHeaders is similar to VerifyHeader, but verifies a batch of headers
+	// concurrently. The method returns a quit channel to abort the operations and
+	// a results channel to retrieve the async verifications (the order is that of
+	// the input slice).
+	VerifyHeaders(chain ChainHeaderReader, headers []*types.Header, seals []bool) (chan<- struct{}, <-chan error)
+
+	// VerifyUncles verifies that the given block's uncles conform to the consensus
+	// rules of a given engine.
+	VerifyUncles(chain ChainReader, block *types.Block) error
+
+	// Prepare initializes the consensus fields of a block header according to the
+	// rules of a particular engine. The changes are executed inline.
+	Prepare(chain ChainHeaderReader, header *types.Header) error
+
+	// Finalize runs any post-transaction state modifications (e.g. block rewards
+	// or process withdrawals) but does not assemble the block.
+	//
+	// Note: The state database might be updated to reflect any consensus rules
+	// that happen at finalization (e.g. block rewards).
+	Finalize(chain ChainHeaderReader, header *types.Header, state core.RWStateDB, txs []*types.Transaction,
+		uncles []*types.Header, withdrawals []*types.Withdrawal)
+
+	// FinalizeAndAssemble runs any post-transaction state modifications (e.g. block
+	// rewards or process withdrawals) and assembles the final block.
+	//
+	// Note: The block header and state database might be updated to reflect any
+	// consensus rules that happen at finalization (e.g. block rewards).
+	FinalizeAndAssemble(chain ChainHeaderReader, header *types.Header, state core.RWStateDB, txs []*types.Transaction,
+		uncles []*types.Header, receipts []*types.Receipt, withdrawals []*types.Withdrawal) (*types.Block, error)
+
+	// Seal generates a new sealing request for the given input block and pushes
+	// the result into the given channel.
+	//
+	// Note, the method returns immediately and will send the result async. More
+	// than one result may also be returned depending on the consensus algorithm.
+	Seal(chain ChainHeaderReader, block *types.Block, results chan<- *types.Block, stop <-chan struct{}) error
+
+	// SealHash returns the hash of a block prior to it being sealed.
+	SealHash(header *types.Header) core.Hash
+
+	// CalcDifficulty is the difficulty adjustment algorithm. It returns the difficulty
+	// that a new block should have.
+	CalcDifficulty(chain ChainHeaderReader, time uint64, parent *types.Header) *big.Int
+
+	// APIs returns the RPC APIs this consensus engine provides.
+	APIs(chain ChainHeaderReader) []core.API
+
+	// Close terminates any background threads maintained by the consensus engine.
+	Close() error
+}