Documentation

Overview

    Package light implements on-demand retrieval capable state and chain objects for the Ethereum Light Client.

    Index

    Constants

    This section is empty.

    Variables

    View Source
    var (
    	ErrNoTrustedCht = errors.New("No trusted canonical hash trie")
    	ErrNoHeader     = errors.New("Header not found")
    
    	ChtFrequency     = uint64(4096)
    	ChtConfirmations = uint64(2048)
    )

      NoOdr is the default context passed to an ODR capable function when the ODR service is not required.

      Functions

      func DeleteTrustedCht

      func DeleteTrustedCht(db ethdb.Database)

      func GetBlock

      func GetBlock(ctx context.Context, odr OdrBackend, hash common.Hash, number uint64) (*types.Block, error)

        GetBlock retrieves an entire block corresponding to the hash, assembling it back from the stored header and body.

        func GetBlockReceipts

        func GetBlockReceipts(ctx context.Context, odr OdrBackend, hash common.Hash, number uint64) (types.Receipts, error)

          GetBlockReceipts retrieves the receipts generated by the transactions included in a block given by its hash.

          func GetBody

          func GetBody(ctx context.Context, odr OdrBackend, hash common.Hash, number uint64) (*types.Body, error)

            GetBody retrieves the block body (transactons, uncles) corresponding to the hash.

            func GetBodyRLP

            func GetBodyRLP(ctx context.Context, odr OdrBackend, hash common.Hash, number uint64) (rlp.RawValue, error)

              GetBodyRLP retrieves the block body (transactions and uncles) in RLP encoding.

              func GetCanonicalHash

              func GetCanonicalHash(ctx context.Context, odr OdrBackend, number uint64) (common.Hash, error)

              func GetHeaderByNumber

              func GetHeaderByNumber(ctx context.Context, odr OdrBackend, number uint64) (*types.Header, error)

              func NewState

              func NewState(ctx context.Context, head *types.Header, odr OdrBackend) *state.StateDB

              func NewStateDatabase

              func NewStateDatabase(ctx context.Context, head *types.Header, odr OdrBackend) state.Database

              func WriteTrustedCht

              func WriteTrustedCht(db ethdb.Database, cht TrustedCht)

              Types

              type BlockRequest

              type BlockRequest struct {
              	OdrRequest
              	Hash   common.Hash
              	Number uint64
              	Rlp    []byte
              }

                BlockRequest is the ODR request type for retrieving block bodies

                func (*BlockRequest) StoreResult

                func (req *BlockRequest) StoreResult(db ethdb.Database)

                  StoreResult stores the retrieved data in local database

                  type ChtNode

                  type ChtNode struct {
                  	Hash common.Hash
                  	Td   *big.Int
                  }

                  type ChtRequest

                  type ChtRequest struct {
                  	OdrRequest
                  	ChtNum, BlockNum uint64
                  	ChtRoot          common.Hash
                  	Header           *types.Header
                  	Td               *big.Int
                  	Proof            []rlp.RawValue
                  }

                    TrieRequest is the ODR request type for state/storage trie entries

                    func (*ChtRequest) StoreResult

                    func (req *ChtRequest) StoreResult(db ethdb.Database)

                      StoreResult stores the retrieved data in local database

                      type CodeRequest

                      type CodeRequest struct {
                      	OdrRequest
                      	Id   *TrieID // references storage trie of the account
                      	Hash common.Hash
                      	Data []byte
                      }

                        CodeRequest is the ODR request type for retrieving contract code

                        func (*CodeRequest) StoreResult

                        func (req *CodeRequest) StoreResult(db ethdb.Database)

                          StoreResult stores the retrieved data in local database

                          type LightChain

                          type LightChain struct {
                          	// contains filtered or unexported fields
                          }

                            LightChain represents a canonical chain that by default only handles block headers, downloading block bodies and receipts on demand through an ODR interface. It only does header validation during chain insertion.

                            func NewLightChain

                            func NewLightChain(odr OdrBackend, config *params.ChainConfig, engine consensus.Engine) (*LightChain, error)

                              NewLightChain returns a fully initialised light chain using information available in the database. It initialises the default Ethereum header validator.

                              func (*LightChain) CurrentHeader

                              func (self *LightChain) CurrentHeader() *types.Header

                                CurrentHeader retrieves the current head header of the canonical chain. The header is retrieved from the HeaderChain's internal cache.

                                func (*LightChain) Engine

                                func (bc *LightChain) Engine() consensus.Engine

                                  Engine retrieves the light chain's consensus engine.

                                  func (*LightChain) GasLimit

                                  func (self *LightChain) GasLimit() *big.Int

                                    GasLimit returns the gas limit of the current HEAD block.

                                    func (*LightChain) Genesis

                                    func (bc *LightChain) Genesis() *types.Block

                                      Genesis returns the genesis block

                                      func (*LightChain) GetBlock

                                      func (self *LightChain) GetBlock(ctx context.Context, hash common.Hash, number uint64) (*types.Block, error)

                                        GetBlock retrieves a block from the database or ODR service by hash and number, caching it if found.

                                        func (*LightChain) GetBlockByHash

                                        func (self *LightChain) GetBlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error)

                                          GetBlockByHash retrieves a block from the database or ODR service by hash, caching it if found.

                                          func (*LightChain) GetBlockByNumber

                                          func (self *LightChain) GetBlockByNumber(ctx context.Context, number uint64) (*types.Block, error)

                                            GetBlockByNumber retrieves a block from the database or ODR service by number, caching it (associated with its hash) if found.

                                            func (*LightChain) GetBlockHashesFromHash

                                            func (self *LightChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash

                                              GetBlockHashesFromHash retrieves a number of block hashes starting at a given hash, fetching towards the genesis block.

                                              func (*LightChain) GetBody

                                              func (self *LightChain) GetBody(ctx context.Context, hash common.Hash) (*types.Body, error)

                                                GetBody retrieves a block body (transactions and uncles) from the database or ODR service by hash, caching it if found.

                                                func (*LightChain) GetBodyRLP

                                                func (self *LightChain) GetBodyRLP(ctx context.Context, hash common.Hash) (rlp.RawValue, error)

                                                  GetBodyRLP retrieves a block body in RLP encoding from the database or ODR service by hash, caching it if found.

                                                  func (*LightChain) GetHeader

                                                  func (self *LightChain) GetHeader(hash common.Hash, number uint64) *types.Header

                                                    GetHeader retrieves a block header from the database by hash and number, caching it if found.

                                                    func (*LightChain) GetHeaderByHash

                                                    func (self *LightChain) GetHeaderByHash(hash common.Hash) *types.Header

                                                      GetHeaderByHash retrieves a block header from the database by hash, caching it if found.

                                                      func (*LightChain) GetHeaderByNumber

                                                      func (self *LightChain) GetHeaderByNumber(number uint64) *types.Header

                                                        GetHeaderByNumber retrieves a block header from the database by number, caching it (associated with its hash) if found.

                                                        func (*LightChain) GetHeaderByNumberOdr

                                                        func (self *LightChain) GetHeaderByNumberOdr(ctx context.Context, number uint64) (*types.Header, error)

                                                          GetHeaderByNumberOdr retrieves a block header from the database or network by number, caching it (associated with its hash) if found.

                                                          func (*LightChain) GetTd

                                                          func (self *LightChain) GetTd(hash common.Hash, number uint64) *big.Int

                                                            GetTd retrieves a block's total difficulty in the canonical chain from the database by hash and number, caching it if found.

                                                            func (*LightChain) GetTdByHash

                                                            func (self *LightChain) GetTdByHash(hash common.Hash) *big.Int

                                                              GetTdByHash retrieves a block's total difficulty in the canonical chain from the database by hash, caching it if found.

                                                              func (*LightChain) HasBlock

                                                              func (bc *LightChain) HasBlock(hash common.Hash, number uint64) bool

                                                                HasBlock checks if a block is fully present in the database or not, caching it if present.

                                                                func (*LightChain) HasHeader

                                                                func (bc *LightChain) HasHeader(hash common.Hash, number uint64) bool

                                                                  HasHeader checks if a block header is present in the database or not, caching it if present.

                                                                  func (*LightChain) InsertHeaderChain

                                                                  func (self *LightChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (int, error)

                                                                    InsertHeaderChain attempts to insert the given header chain in to the local chain, possibly creating a reorg. If an error is returned, it will return the index number of the failing header as well an error describing what went wrong.

                                                                    The verify parameter can be used to fine tune whether nonce verification should be done or not. The reason behind the optional check is because some of the header retrieval mechanisms already need to verfy nonces, as well as because nonces can be verified sparsely, not needing to check each.

                                                                    In the case of a light chain, InsertHeaderChain also creates and posts light chain events when necessary.

                                                                    func (*LightChain) LastBlockHash

                                                                    func (self *LightChain) LastBlockHash() common.Hash

                                                                      LastBlockHash return the hash of the HEAD block.

                                                                      func (*LightChain) LockChain

                                                                      func (self *LightChain) LockChain()

                                                                        LockChain locks the chain mutex for reading so that multiple canonical hashes can be retrieved while it is guaranteed that they belong to the same version of the chain

                                                                        func (*LightChain) Odr

                                                                        func (self *LightChain) Odr() OdrBackend

                                                                          Odr returns the ODR backend of the chain

                                                                          func (*LightChain) Reset

                                                                          func (bc *LightChain) Reset()

                                                                            Reset purges the entire blockchain, restoring it to its genesis state.

                                                                            func (*LightChain) ResetWithGenesisBlock

                                                                            func (bc *LightChain) ResetWithGenesisBlock(genesis *types.Block)

                                                                              ResetWithGenesisBlock purges the entire blockchain, restoring it to the specified genesis state.

                                                                              func (*LightChain) Rollback

                                                                              func (self *LightChain) Rollback(chain []common.Hash)

                                                                                Rollback is designed to remove a chain of links from the database that aren't certain enough to be valid.

                                                                                func (*LightChain) SetHead

                                                                                func (bc *LightChain) SetHead(head uint64)

                                                                                  SetHead rewinds the local chain to a new head. Everything above the new head will be deleted and the new one set.

                                                                                  func (*LightChain) Status

                                                                                  func (self *LightChain) Status() (td *big.Int, currentBlock common.Hash, genesisBlock common.Hash)

                                                                                    Status returns status information about the current chain such as the HEAD Td, the HEAD hash and the hash of the genesis block.

                                                                                    func (*LightChain) Stop

                                                                                    func (bc *LightChain) Stop()

                                                                                      Stop stops the blockchain service. If any imports are currently in progress it will abort them using the procInterrupt.

                                                                                      func (*LightChain) SubscribeChainEvent

                                                                                      func (self *LightChain) SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription

                                                                                        SubscribeChainEvent registers a subscription of ChainEvent.

                                                                                        func (*LightChain) SubscribeChainHeadEvent

                                                                                        func (self *LightChain) SubscribeChainHeadEvent(ch chan<- core.ChainHeadEvent) event.Subscription

                                                                                          SubscribeChainHeadEvent registers a subscription of ChainHeadEvent.

                                                                                          func (*LightChain) SubscribeChainSideEvent

                                                                                          func (self *LightChain) SubscribeChainSideEvent(ch chan<- core.ChainSideEvent) event.Subscription

                                                                                            SubscribeChainSideEvent registers a subscription of ChainSideEvent.

                                                                                            func (*LightChain) SubscribeLogsEvent

                                                                                            func (self *LightChain) SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription

                                                                                              SubscribeLogsEvent implements the interface of filters.Backend LightChain does not send logs events, so return an empty subscription.

                                                                                              func (*LightChain) SubscribeRemovedLogsEvent

                                                                                              func (self *LightChain) SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent) event.Subscription

                                                                                                SubscribeRemovedLogsEvent implements the interface of filters.Backend LightChain does not send core.RemovedLogsEvent, so return an empty subscription.

                                                                                                func (*LightChain) SyncCht

                                                                                                func (self *LightChain) SyncCht(ctx context.Context) bool

                                                                                                func (*LightChain) UnlockChain

                                                                                                func (self *LightChain) UnlockChain()

                                                                                                  UnlockChain unlocks the chain mutex

                                                                                                  type OdrBackend

                                                                                                  type OdrBackend interface {
                                                                                                  	Database() ethdb.Database
                                                                                                  	Retrieve(ctx context.Context, req OdrRequest) error
                                                                                                  }

                                                                                                    OdrBackend is an interface to a backend service that handles ODR retrievals type

                                                                                                    type OdrRequest

                                                                                                    type OdrRequest interface {
                                                                                                    	StoreResult(db ethdb.Database)
                                                                                                    }

                                                                                                      OdrRequest is an interface for retrieval requests

                                                                                                      type ReceiptsRequest

                                                                                                      type ReceiptsRequest struct {
                                                                                                      	OdrRequest
                                                                                                      	Hash     common.Hash
                                                                                                      	Number   uint64
                                                                                                      	Receipts types.Receipts
                                                                                                      }

                                                                                                        ReceiptsRequest is the ODR request type for retrieving block bodies

                                                                                                        func (*ReceiptsRequest) StoreResult

                                                                                                        func (req *ReceiptsRequest) StoreResult(db ethdb.Database)

                                                                                                          StoreResult stores the retrieved data in local database

                                                                                                          type TrieID

                                                                                                          type TrieID struct {
                                                                                                          	BlockHash, Root common.Hash
                                                                                                          	BlockNumber     uint64
                                                                                                          	AccKey          []byte
                                                                                                          }

                                                                                                            TrieID identifies a state or account storage trie

                                                                                                            func StateTrieID

                                                                                                            func StateTrieID(header *types.Header) *TrieID

                                                                                                              StateTrieID returns a TrieID for a state trie belonging to a certain block header.

                                                                                                              func StorageTrieID

                                                                                                              func StorageTrieID(state *TrieID, addrHash, root common.Hash) *TrieID

                                                                                                                StorageTrieID returns a TrieID for a contract storage trie at a given account of a given state trie. It also requires the root hash of the trie for checking Merkle proofs.

                                                                                                                type TrieRequest

                                                                                                                type TrieRequest struct {
                                                                                                                	OdrRequest
                                                                                                                	Id    *TrieID
                                                                                                                	Key   []byte
                                                                                                                	Proof []rlp.RawValue
                                                                                                                }

                                                                                                                  TrieRequest is the ODR request type for state/storage trie entries

                                                                                                                  func (*TrieRequest) StoreResult

                                                                                                                  func (req *TrieRequest) StoreResult(db ethdb.Database)

                                                                                                                    StoreResult stores the retrieved data in local database

                                                                                                                    type TrustedCht

                                                                                                                    type TrustedCht struct {
                                                                                                                    	Number uint64
                                                                                                                    	Root   common.Hash
                                                                                                                    }

                                                                                                                    func GetTrustedCht

                                                                                                                    func GetTrustedCht(db ethdb.Database) TrustedCht

                                                                                                                    type TxPool

                                                                                                                    type TxPool struct {
                                                                                                                    	// contains filtered or unexported fields
                                                                                                                    }

                                                                                                                      TxPool implements the transaction pool for light clients, which keeps track of the status of locally created transactions, detecting if they are included in a block (mined) or rolled back. There are no queued transactions since we always receive all locally signed transactions in the same order as they are created.

                                                                                                                      func NewTxPool

                                                                                                                      func NewTxPool(config *params.ChainConfig, chain *LightChain, relay TxRelayBackend) *TxPool

                                                                                                                        NewTxPool creates a new light transaction pool

                                                                                                                        func (*TxPool) Add

                                                                                                                        func (self *TxPool) Add(ctx context.Context, tx *types.Transaction) error

                                                                                                                          Add adds a transaction to the pool if valid and passes it to the tx relay backend

                                                                                                                          func (*TxPool) AddBatch

                                                                                                                          func (self *TxPool) AddBatch(ctx context.Context, txs []*types.Transaction)

                                                                                                                            AddTransactions adds all valid transactions to the pool and passes them to the tx relay backend

                                                                                                                            func (*TxPool) Content

                                                                                                                            func (self *TxPool) Content() (map[common.Address]types.Transactions, map[common.Address]types.Transactions)

                                                                                                                              Content retrieves the data content of the transaction pool, returning all the pending as well as queued transactions, grouped by account and nonce.

                                                                                                                              func (*TxPool) GetNonce

                                                                                                                              func (pool *TxPool) GetNonce(ctx context.Context, addr common.Address) (uint64, error)

                                                                                                                                GetNonce returns the "pending" nonce of a given address. It always queries the nonce belonging to the latest header too in order to detect if another client using the same key sent a transaction.

                                                                                                                                func (*TxPool) GetTransaction

                                                                                                                                func (tp *TxPool) GetTransaction(hash common.Hash) *types.Transaction

                                                                                                                                  GetTransaction returns a transaction if it is contained in the pool and nil otherwise.

                                                                                                                                  func (*TxPool) GetTransactions

                                                                                                                                  func (self *TxPool) GetTransactions() (txs types.Transactions, err error)

                                                                                                                                    GetTransactions returns all currently processable transactions. The returned slice may be modified by the caller.

                                                                                                                                    func (*TxPool) RemoveTransactions

                                                                                                                                    func (self *TxPool) RemoveTransactions(txs types.Transactions)

                                                                                                                                      RemoveTransactions removes all given transactions from the pool.

                                                                                                                                      func (*TxPool) RemoveTx

                                                                                                                                      func (pool *TxPool) RemoveTx(hash common.Hash)

                                                                                                                                        RemoveTx removes the transaction with the given hash from the pool.

                                                                                                                                        func (*TxPool) Stats

                                                                                                                                        func (pool *TxPool) Stats() (pending int)

                                                                                                                                          Stats returns the number of currently pending (locally created) transactions

                                                                                                                                          func (*TxPool) Stop

                                                                                                                                          func (pool *TxPool) Stop()

                                                                                                                                            Stop stops the light transaction pool

                                                                                                                                            func (*TxPool) SubscribeTxPreEvent

                                                                                                                                            func (pool *TxPool) SubscribeTxPreEvent(ch chan<- core.TxPreEvent) event.Subscription

                                                                                                                                              SubscribeTxPreEvent registers a subscription of core.TxPreEvent and starts sending event to the given channel.

                                                                                                                                              type TxRelayBackend

                                                                                                                                              type TxRelayBackend interface {
                                                                                                                                              	Send(txs types.Transactions)
                                                                                                                                              	NewHead(head common.Hash, mined []common.Hash, rollback []common.Hash)
                                                                                                                                              	Discard(hashes []common.Hash)
                                                                                                                                              }

                                                                                                                                                TxRelayBackend provides an interface to the mechanism that forwards transacions to the ETH network. The implementations of the functions should be non-blocking.

                                                                                                                                                Send instructs backend to forward new transactions NewHead notifies backend about a new head after processed by the tx pool,

                                                                                                                                                including  mined and rolled back transactions since the last event
                                                                                                                                                

                                                                                                                                                Discard notifies backend about transactions that should be discarded either

                                                                                                                                                because they have been replaced by a re-send or because they have been mined
                                                                                                                                                long ago and no rollback is expected