Network.Haskoin.Block.Headers

Block chain header synchronization and proof-of-work consensus functions.

Documentation

data BlockNode

Data structure representing a block header and its position in the block chain.

Constructors

BlockNode

non-Genesis block header

Fields

• nodeHeader :: !BlockHeader
• nodeHeight :: !BlockHeight
• nodeWork :: !BlockWork

  accumulated work so far

• nodeSkip :: !BlockHash

  akip magic block hash

GenesisNode

Genesis block header

Fields

• nodeHeader :: !BlockHeader
• nodeHeight :: !BlockHeight
• nodeWork :: !BlockWork

  accumulated work so far

Instances

Eq BlockNode

Defined in Network.Haskoin.Block.Headers

Methods

(==) :: BlockNode -> BlockNode -> Bool

(/=) :: BlockNode -> BlockNode -> Bool

Ord BlockNode

Defined in Network.Haskoin.Block.Headers

Methods

compare :: BlockNode -> BlockNode -> Ordering

(<) :: BlockNode -> BlockNode -> Bool

(<=) :: BlockNode -> BlockNode -> Bool

(>) :: BlockNode -> BlockNode -> Bool

(>=) :: BlockNode -> BlockNode -> Bool

max :: BlockNode -> BlockNode -> BlockNode

min :: BlockNode -> BlockNode -> BlockNode

Read BlockNode

Defined in Network.Haskoin.Block.Headers

Methods

readsPrec :: Int -> ReadS BlockNode

readList :: ReadS [BlockNode]

readPrec :: ReadPrec BlockNode

readListPrec :: ReadPrec [BlockNode]

Show BlockNode

Defined in Network.Haskoin.Block.Headers

Methods

showsPrec :: Int -> BlockNode -> ShowS

show :: BlockNode -> String

showList :: [BlockNode] -> ShowS

Generic BlockNode

Defined in Network.Haskoin.Block.Headers

Associated Types

type Rep BlockNode :: * -> *

Methods

from :: BlockNode -> Rep BlockNode x

to :: Rep BlockNode x -> BlockNode

Hashable BlockNode

Defined in Network.Haskoin.Block.Headers

Methods

hashWithSalt :: Int -> BlockNode -> Int

hash :: BlockNode -> Int

Serialize BlockNode

Defined in Network.Haskoin.Block.Headers

Methods

put :: Putter BlockNode

get :: Get BlockNode

type Rep BlockNode

Defined in Network.Haskoin.Block.Headers

type Rep BlockNode = D1 (MetaData "BlockNode" "Network.Haskoin.Block.Headers" "haskoin-core-0.8.2-DBbfowLuwQJDnYGV2ClFSV" False) (C1 (MetaCons "BlockNode" PrefixI True) ((S1 (MetaSel (Just "nodeHeader") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockHeader) :*: S1 (MetaSel (Just "nodeHeight") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockHeight)) :*: (S1 (MetaSel (Just "nodeWork") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockWork) :*: S1 (MetaSel (Just "nodeSkip") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockHash))) :+: C1 (MetaCons "GenesisNode" PrefixI True) (S1 (MetaSel (Just "nodeHeader") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockHeader) :*: (S1 (MetaSel (Just "nodeHeight") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockHeight) :*: S1 (MetaSel (Just "nodeWork") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockWork))))

class Monad m => BlockHeaders m where

Typeclass for block header chain storage monad.

Minimal complete definition

addBlockHeader, getBlockHeader, getBestBlockHeader, setBestBlockHeader

Methods

addBlockHeader :: BlockNode -> m ()

Add a new BlockNode to the chain. Does not validate.

getBlockHeader :: BlockHash -> m (Maybe BlockNode)

Get a BlockNode associated with a BlockHash.

getBestBlockHeader :: m BlockNode

Locate the BlockNode for the highest block in the chain

setBestBlockHeader :: BlockNode -> m ()

Set the highest block in the chain.

addBlockHeaders :: [BlockNode] -> m ()

Add a continuous bunch of block headers the chain. Does not validate.

Instances

Monad m => BlockHeaders (StateT HeaderMemory m)

Defined in Network.Haskoin.Block.Headers

Methods

addBlockHeader :: BlockNode -> StateT HeaderMemory m ()

getBlockHeader :: BlockHash -> StateT HeaderMemory m (Maybe BlockNode)

getBestBlockHeader :: StateT HeaderMemory m BlockNode

setBestBlockHeader :: BlockNode -> StateT HeaderMemory m ()

addBlockHeaders :: [BlockNode] -> StateT HeaderMemory m ()

type BlockWork = Integer

Represents accumulated work in the block chain so far.

genesisNode :: Network -> BlockNode

Build the genesis BlockNode for the supplied Network.

genesisBlock :: Network -> Block

Generate the entire Genesis block for Network.

isGenesis :: BlockNode -> Bool

Is the provided BlockNode the Genesis block?

chooseBest :: BlockNode -> BlockNode -> BlockNode

Compare two blocks to get the best.

Header Chain Storage Functions

parentBlock :: BlockHeaders m => BlockHeader -> m (Maybe BlockNode)

Block's parent. If the block header is in the store, its parent must also be there. No block header get deleted or pruned from the store.

getParents

Arguments

:: BlockHeaders m

=> Int

-> BlockNode

-> m [BlockNode]

starts from immediate parent

Get a number of parents for the provided block.

getAncestor :: BlockHeaders m => BlockHeight -> BlockNode -> m (Maybe BlockNode)

Get the ancestor of the provided BlockNode at the specified BlockHeight.

splitPoint :: BlockHeaders m => BlockNode -> BlockNode -> m BlockNode

Find the last common block ancestor between provided block headers.

connectBlocks

Arguments

:: BlockHeaders m

=> Network

-> Timestamp

current time

-> [BlockHeader]

-> m (Either String [BlockNode])

Validate a list of continuous block headers and import them to the block chain. Return Left on failure with error information.

connectBlock

Arguments

:: BlockHeaders m

=> Network

-> Timestamp

current time

-> BlockHeader

-> m (Either String BlockNode)

Validate and connect single block header to the block chain. Return Left if fails to be validated.

blockLocator :: BlockHeaders m => BlockNode -> m BlockLocator

Get block locator.

In-Memory Header Chain Store

data HeaderMemory

Memory-based header tree.

Constructors

HeaderMemory

Fields

• memoryHeaderMap :: !BlockMap
• memoryBestHeader :: !BlockNode

Instances

Eq HeaderMemory

Defined in Network.Haskoin.Block.Headers

Methods

(==) :: HeaderMemory -> HeaderMemory -> Bool

(/=) :: HeaderMemory -> HeaderMemory -> Bool

Read HeaderMemory

Defined in Network.Haskoin.Block.Headers

Methods

readsPrec :: Int -> ReadS HeaderMemory

readList :: ReadS [HeaderMemory]

readPrec :: ReadPrec HeaderMemory

readListPrec :: ReadPrec [HeaderMemory]

Show HeaderMemory

Defined in Network.Haskoin.Block.Headers

Methods

showsPrec :: Int -> HeaderMemory -> ShowS

show :: HeaderMemory -> String

showList :: [HeaderMemory] -> ShowS

Generic HeaderMemory

Defined in Network.Haskoin.Block.Headers

Associated Types

type Rep HeaderMemory :: * -> *

Methods

from :: HeaderMemory -> Rep HeaderMemory x

to :: Rep HeaderMemory x -> HeaderMemory

Hashable HeaderMemory

Defined in Network.Haskoin.Block.Headers

Methods

hashWithSalt :: Int -> HeaderMemory -> Int

hash :: HeaderMemory -> Int

Monad m => BlockHeaders (StateT HeaderMemory m)

Defined in Network.Haskoin.Block.Headers

Methods

addBlockHeader :: BlockNode -> StateT HeaderMemory m ()

getBlockHeader :: BlockHash -> StateT HeaderMemory m (Maybe BlockNode)

getBestBlockHeader :: StateT HeaderMemory m BlockNode

setBestBlockHeader :: BlockNode -> StateT HeaderMemory m ()

addBlockHeaders :: [BlockNode] -> StateT HeaderMemory m ()

type Rep HeaderMemory

Defined in Network.Haskoin.Block.Headers

type Rep HeaderMemory = D1 (MetaData "HeaderMemory" "Network.Haskoin.Block.Headers" "haskoin-core-0.8.2-DBbfowLuwQJDnYGV2ClFSV" False) (C1 (MetaCons "HeaderMemory" PrefixI True) (S1 (MetaSel (Just "memoryHeaderMap") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockMap) :*: S1 (MetaSel (Just "memoryBestHeader") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 BlockNode)))

type ShortBlockHash = Word64

Short version of the block hash. Uses the good end of the hash (the part that doesn't have a long string of zeroes).

type BlockMap = HashMap ShortBlockHash ShortByteString

Memory-based map to a serialized BlockNode data structure. ShortByteString is used to avoid memory fragmentation and make the data structure compact.

shortBlockHash :: BlockHash -> ShortBlockHash

Calculate short block hash taking eight non-zero bytes from the 16-byte hash. This function will take the bytes that are not on the zero-side of the hash, making colissions between short block hashes difficult.

initialChain :: Network -> HeaderMemory

Initialize memory-based chain.

genesisMap :: Network -> BlockMap

Initialize map for memory-based chain.

Helper Functions

appendBlocks

Arguments

:: Network

-> Word32

random seed

-> BlockHeader

-> Int

-> [BlockHeader]

Generate and append new blocks (mining). Only practical in regtest network.

validBlock

Arguments

:: Network

-> Timestamp

current time

-> BlockNode

best block

-> BlockNode

immediate parent

-> [BlockNode]

10 parents above

-> BlockHeader

header to validate

-> BlockNode

skip node (black magic)

-> Either String BlockNode

Validate this block header. Build a BlockNode if successful.

validCP

Arguments

:: Network

-> BlockHeight

new child height

-> BlockHash

new child hash

-> Bool

Verify that checkpoint location is valid.

afterLastCP

Arguments

:: Network

-> BlockHeight

best height

-> BlockHeight

new imported block height

-> Bool

New block height above the last checkpoint imported. Used to prevent a reorg below the highest checkpoint that was already imported.

bip34

Arguments

:: Network

-> BlockHeight

new child height

-> BlockHash

new child hash

-> Bool

This block should be at least version 2 (BIP34). Block height must be included in the coinbase transaction to prevent non-unique transaction hashes.

validVersion

Arguments

:: Network

-> BlockHeight

new child height

-> Word32

new child version

-> Bool

Check if the provided block height and version are valid.

lastNoMinDiff :: BlockHeaders m => Network -> BlockNode -> m BlockNode

Find last block with normal, as opposed to minimum difficulty (for test networks).

nextWorkRequired :: BlockHeaders m => Network -> BlockNode -> BlockHeader -> m Word32

Returns the work required on a block header given the previous block. This coresponds to bitcoind function GetNextWorkRequired in main.cpp.

nextEdaWorkRequired :: BlockHeaders m => Network -> BlockNode -> BlockHeader -> m Word32

Find out the next amount of work required according to the Emergency Difficulty Adjustment (EDA) algorithm from Bitcoin Cash.

nextDaaWorkRequired :: BlockHeaders m => Network -> BlockNode -> BlockHeader -> m Word32

Find the next amount of work required according to the Difficulty Adjustment Algorithm (DAA) from Bitcoin Cash.

computeTarget :: Network -> BlockNode -> BlockNode -> Integer

Compute Bitcoin Cash DAA target for a new block.

getSuitableBlock :: BlockHeaders m => BlockNode -> m BlockNode

Get suitable block for Bitcoin Cash DAA computation.

nextPowWorkRequired :: BlockHeaders m => Network -> BlockNode -> BlockHeader -> m Word32

Returns the work required on a block header given the previous block. This coresponds to bitcoind function GetNextWorkRequired in main.cpp.

calcNextWork

Arguments

:: Network

-> BlockHeader

last block in previous retarget (parent)

-> Timestamp

timestamp of first block in previous retarget

-> Word32

Computes the work required for the first block in a new retarget period.

isValidPOW :: Network -> BlockHeader -> Bool

Returns True if the difficulty target (bits) of the header is valid and the proof of work of the header matches the advertised difficulty target. This function corresponds to the function CheckProofOfWork from bitcoind in main.cpp.

blockPOW :: BlockHash -> Integer

Returns the proof of work of a block header hash as an Integer number.

headerWork :: BlockHeader -> Integer

Returns the work represented by this block. Work is defined as the number of tries needed to solve a block in the average case with respect to the target.

diffInterval :: Network -> Word32

Number of blocks on average between difficulty cycles (2016 blocks).

blockLocatorNodes :: BlockHeaders m => BlockNode -> m [BlockNode]

Get list of blocks for a block locator.

mineBlock :: Network -> Word32 -> BlockHeader -> BlockHeader

Become rich beyond your wildest dreams.