Haskoin.Transaction.Builder

Code to simplify transaction creation, signing, fee calculation and coin selection.

Transaction Builder

buildAddrTx :: Network -> Ctx -> [OutPoint] -> [(Text, Word64)] -> Either String Tx

Build a transaction by providing a list of outpoints as inputs and a list of recipient addresses and amounts as outputs.

buildTx :: Ctx -> [OutPoint] -> [(ScriptOutput, Word64)] -> Tx

Build a transaction by providing a list of outpoints as inputs and a list of ScriptOutput and amounts as outputs.

buildInput

Arguments

:: Network

-> Ctx

-> Tx

transaction where input will be added

-> Int

input index where signature will go

-> ScriptOutput

output script being spent

-> Word64

amount of previous output

-> Maybe RedeemScript

redeem script if pay-to-script-hash

-> TxSignature

-> PublicKey

-> Either String ScriptInput

Construct an input for a transaction given a signature, public key and data about the previous output.

data SigInput

Data type used to specify the signing parameters of a transaction input. To sign an input, the previous output script, outpoint and sighash are required. When signing a pay to script hash output, an additional redeem script is required.

Constructors

SigInput

Fields

• script :: !ScriptOutput

  output script to spend ^ output script value

• value :: !Word64

  output script value ^ outpoint to spend

• outpoint :: !OutPoint

  outpoint to spend ^ signature type

• sighash :: !SigHash

  signature type ^ redeem script

• redeem :: !(Maybe RedeemScript)

  redeem script

Instances

Generic SigInput

Defined in Haskoin.Transaction.Builder.Sign

Associated Types

type Rep SigInput :: Type -> Type

Methods

from :: SigInput -> Rep SigInput x

to :: Rep SigInput x -> SigInput

Read SigInput

Defined in Haskoin.Transaction.Builder.Sign

Methods

readsPrec :: Int -> ReadS SigInput

readList :: ReadS [SigInput]

readPrec :: ReadPrec SigInput

readListPrec :: ReadPrec [SigInput]

Show SigInput

Defined in Haskoin.Transaction.Builder.Sign

Methods

showsPrec :: Int -> SigInput -> ShowS

show :: SigInput -> String

showList :: [SigInput] -> ShowS

NFData SigInput

Defined in Haskoin.Transaction.Builder.Sign

Methods

rnf :: SigInput -> ()

Eq SigInput

Defined in Haskoin.Transaction.Builder.Sign

Methods

(==) :: SigInput -> SigInput -> Bool

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

MarshalJSON Ctx SigInput

Defined in Haskoin.Transaction.Builder.Sign

Methods

marshalValue :: Ctx -> SigInput -> Value

marshalEncoding :: Ctx -> SigInput -> Encoding

unmarshalValue :: Ctx -> Value -> Parser SigInput

type Rep SigInput

Defined in Haskoin.Transaction.Builder.Sign

type Rep SigInput = D1 ('MetaData "SigInput" "Haskoin.Transaction.Builder.Sign" "haskoin-core-1.1.0-EPeWWz60EKPlWai44F9WC" 'False) (C1 ('MetaCons "SigInput" 'PrefixI 'True) ((S1 ('MetaSel ('Just "script") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 ScriptOutput) :*: S1 ('MetaSel ('Just "value") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Word64)) :*: (S1 ('MetaSel ('Just "outpoint") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 OutPoint) :*: (S1 ('MetaSel ('Just "sighash") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 SigHash) :*: S1 ('MetaSel ('Just "redeem") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 (Maybe RedeemScript))))))

signTx

Arguments

:: Network

-> Ctx

-> Tx

transaction to sign

-> [SigInput]

signing parameters

-> [SecKey]

private keys to sign with

-> Either String Tx

signed transaction

Sign a transaction by providing the SigInput signing parameters and a list of private keys. The signature is computed deterministically as defined in RFC-6979.

Example: P2SH-P2WKH

sigIn = SigInput (PayWitnessPKHash h) 100000 op sigHashAll Nothing
signedTx = signTx btc unsignedTx [sigIn] [key]

Example: P2SH-P2WSH multisig

sigIn = SigInput (PayWitnessScriptHash h) 100000 op sigHashAll (Just $ PayMulSig [p1,p2,p3] 2)
signedTx = signTx btc unsignedTx [sigIn] [k1,k3]

signNestedWitnessTx

Arguments

:: Network

-> Ctx

-> Tx

transaction to sign

-> [SigInput]

signing parameters

-> [SecKey]

private keys to sign with

-> Either String Tx

signed transaction

This function differs from signTx by assuming all segwit inputs are P2SH-nested. Use the same signing parameters for segwit inputs as in signTx.

makeSignature :: Network -> Ctx -> Tx -> Int -> SigInput -> PrivateKey -> TxSignature

Produce a structured representation of a deterministic (RFC-6979) signature over an input.

signInput :: Network -> Ctx -> Tx -> Int -> SigInput -> PrivateKey -> Either String Tx

Sign a single input in a transaction deterministically (RFC-6979).

signNestedInput :: Network -> Ctx -> Tx -> Int -> SigInput -> PrivateKey -> Either String Tx

Like signInput but treat segwit inputs as nested

verifyStdTx :: Network -> Ctx -> Tx -> [(ScriptOutput, Word64, OutPoint)] -> Bool

Verify if a transaction is valid and all of its inputs are standard.

mergeTxs :: Network -> Ctx -> [Tx] -> [(ScriptOutput, Word64, OutPoint)] -> Either String Tx

Merge partially-signed multisig transactions. This function does not support segwit and P2SH-segwit inputs. Use PSBTs to merge transactions with segwit inputs.

sigKeys :: Ctx -> ScriptOutput -> Maybe RedeemScript -> [SecKey] -> Either String [PrivateKey]

Find from the list of provided private keys which one is required to sign the ScriptOutput.

mergeTxInput :: Network -> Ctx -> [Tx] -> Tx -> ((ScriptOutput, Word64), Int) -> Either String Tx

Merge input from partially-signed multisig transactions. This function does not support segwit and P2SH-segwit inputs.

findSigInput :: [SigInput] -> [TxIn] -> [(SigInput, Int)]

Order the SigInput with respect to the transaction inputs. This allows the user to provide the SigInput in any order. Users can also provide only a partial set of SigInput entries.

verifyStdInput :: Network -> Ctx -> Tx -> Int -> ScriptOutput -> Word64 -> Bool

Verify if a transaction input is valid and standard.

Coin Selection

class Coin c where

Any type can be used as a Coin if it can provide a value in Satoshi. The value is used in coin selection algorithms.

Methods

coinValue :: c -> Word64

Instances

Coin TestCoin

Defined in Haskoin.Util.Arbitrary.Transaction

Methods

coinValue :: TestCoin -> Word64

chooseCoins

Arguments

:: Coin c

=> Word64

value to send

-> Word64

fee per byte

-> Int

number of outputs (including change)

-> Bool

try to find better solutions

-> [c]

list of ordered coins to choose from

-> Either String ([c], Word64)

coin selection and change

Coin selection algorithm for normal (non-multisig) transactions. This function returns the selected coins together with the amount of change to send back to yourself, taking the fee into account.

chooseCoinsSink

Arguments

:: (Monad m, Coin c)

=> Word64

value to send

-> Word64

fee per byte

-> Int

number of outputs (including change)

-> Bool

try to find better solution

-> ConduitT c Void m (Either String ([c], Word64))

coin selection and change

Coin selection algorithm for normal (non-multisig) transactions. This function returns the selected coins together with the amount of change to send back to yourself, taking the fee into account. This version uses a Sink for conduit-based coin selection.

chooseMSCoins

Arguments

:: Coin c

=> Word64

value to send

-> Word64

fee per byte

-> (Int, Int)

m of n multisig

-> Int

number of outputs (including change)

-> Bool

try to find better solution

-> [c]

-> Either String ([c], Word64)

coin selection change amount

Coin selection algorithm for multisig transactions. This function returns the selected coins together with the amount of change to send back to yourself, taking the fee into account. This function assumes all the coins are script hash outputs that send funds to a multisignature address.

chooseMSCoinsSink

Arguments

:: (Monad m, Coin c)

=> Word64

value to send

-> Word64

fee per byte

-> (Int, Int)

m of n multisig

-> Int

number of outputs (including change)

-> Bool

try to find better solution

-> ConduitT c Void m (Either String ([c], Word64))

coin selection and change

Coin selection algorithm for multisig transactions. This function returns the selected coins together with the amount of change to send back to yourself, taking the fee into account. This function assumes all the coins are script hash outputs that send funds to a multisignature address. This version uses a Sink if you need conduit-based coin selection.

countMulSig :: Network -> Ctx -> Tx -> Script -> Word64 -> Int -> [PubKey] -> [TxSignature] -> Int

Count the number of valid signatures for a multi-signature transaction.

greedyAddSink

Arguments

:: (Monad m, Coin c)

=> Word64

value to send

-> (Int -> Word64)

coin count to fee function

-> Bool

try to find better solutions

-> ConduitT c Void m (Maybe ([c], Word64))

coin selection and change

Select coins greedily by starting from an empty solution. If the continue flag is set, the algorithm will try to find a better solution in the stream after a solution is found. If the next solution found is not strictly better than the previously found solution, the algorithm stops and returns the previous solution. If the continue flag is not set, the algorithm will return the first solution it finds in the stream.

guessTxFee :: Word64 -> Int -> Int -> Word64

Estimate tranasction fee to pay based on transaction size estimation.

guessMSTxFee :: Word64 -> (Int, Int) -> Int -> Int -> Word64

Same as guessTxFee but for multisig transactions.

guessTxSize

Arguments

:: Int

number of regular transaction inputs

-> [(Int, Int)]

multisig m of n for each input

-> Int

number of P2PKH outputs

-> Int

number of P2SH outputs

-> Int

upper bound on transaction size

Computes an upper bound on the size of a transaction based on some known properties of the transaction.

guessMSSize :: (Int, Int) -> Int

Size of a multisig P2SH input.