CoinSelection class

Represents a selection of inputs to fund a transaction. If the inputs provide sufficient value to cover the ouputs and fee for a transaction that isn't too large, ready shall be true and it is possible to obtain a signable transaction.

Constructors

CoinSelection.new({int version = Transaction.currentVersion, required Iterable<InputCandidate> selected, required Iterable<Output> recipients, required Program changeProgram, required BigInt feePerKb, required BigInt minFee, required BigInt minChange, int locktime = 0})
Selects all the inputs from selected to send to the recipients outputs and provide change to the changeProgram. The feePerKb specifies the required fee in sats per KB with a minimum fee specified with minFee. The minChange is the minimum allowed change.
CoinSelection.inOrderUntilEnough({int version = Transaction.currentVersion, required Iterable<InputCandidate> candidates, required Iterable<Output> recipients, required Program changeProgram, required BigInt feePerKb, required BigInt minFee, required BigInt minChange, int locktime = 0, bool randomise = false, int maxCandidates = 6800})
A simple selection algorithm that selects inputs from the candidates in the order that they are given until the required amount has been reached. If there are not enough coins, all shall be selected and enoughFunds shall be false. If randomise is set to true, the order of inputs shall be randomised after being selected. This is useful for candidates that are not already randomised as it may avoid giving clues to the algorithm being used. The algorithm will only take upto 6800 candidates by default to avoid taking too long and due to size limitations. This can be changed with maxCandidates.
factory
CoinSelection.largestFirst({int version = Transaction.currentVersion, required Iterable<InputCandidate> candidates, required Iterable<Output> recipients, required Program changeProgram, required BigInt feePerKb, required BigInt minFee, required BigInt minChange, int locktime = 0})
A simple selection algorithm that selects inputs from the candidates starting from the largest value until the required amount has been reached. The order of the selected inputs are randomised.
factory
CoinSelection.optimal({int version = Transaction.currentVersion, required Iterable<InputCandidate> candidates, required Iterable<Output> recipients, required Program changeProgram, required BigInt feePerKb, required BigInt minFee, required BigInt minChange, int locktime = 0})
A useful default coin selection algorithm. Currently this will first select candidates at random until the required input amount is reached. If the resulting transaction is too large or not enough funds have been reached it will fall back to adding the largest input values first.
factory
CoinSelection.random({int version = Transaction.currentVersion, required Iterable<InputCandidate> candidates, required Iterable<Output> recipients, required Program changeProgram, required BigInt feePerKb, required BigInt minFee, required BigInt minChange, int locktime = 0})
A simple selection algorithm that selects inputs randomly from the candidates until the required amount has been reached.
factory

Properties

changeless → bool
True when the change output is omitted
no setter
changeProgram → Program
final
changeValue ↔ BigInt
The value of the change output. This is 0 for a changeless transaction or negative if there aren't enough funds.
latefinal
enoughFunds → bool
True when the input value covers the outputs and fee
no setter
fee ↔ BigInt
The fee to be paid by the transaction
latefinal
feePerKb → BigInt
final
hashCode → int
The hash code for this object.
no setterinherited
inputValue ↔ BigInt
The total value of selected inputs
latefinal
locktime → int
final
minChange → BigInt
final
minFee → BigInt
final
ready → bool
True if a signable solution has been found
no setter
recipients → List<Output>
final
recipientValue ↔ BigInt
The total value of all recipient outputs
latefinal
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
selected → List<InputCandidate>
final
signedSize ↔ int
The maximum size of the transaction after being fully signed
latefinal
tooLarge → bool
True if the resulting fully signed transaction will be too large
no setter
transaction → Transaction
Obtains the transaction with selected inputs and outputs including any change at a random location, ready to be signed. Throws InsufficientFunds if there is not enough input value to meet the output value and fee, or TransactionTooLarge if the resulting signed transaction would be too large.
no setter
version → int
final

Methods

noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited