Transaction (Class)

A Kaspa transaction.

Represents a complete transaction with inputs, outputs, and metadata. Transactions are the fundamental unit of value transfer on the Kaspa network.

gas property writable

gas: int

The gas limit for smart contract execution.

id property

id: str

The transaction ID (hash) as a hex string.

inputs property writable

inputs: list[TransactionInput]

The list of transaction inputs spending previous outputs.

lock_time property writable

lock_time: int

The transaction lock time (DAA score or Unix timestamp before which the transaction cannot be included).

mass property writable

mass: int

The transaction mass used for fee calculation.

Alias of storage_mass, retained for compatibility with the WASM SDK and earlier releases of this package.

outputs property writable

outputs: list[TransactionOutput]

The list of transaction outputs defining value destinations.

payload property writable

payload: str

The transaction payload data as a hex string.

storage_mass property writable

storage_mass: int

The transaction storage mass used for fee calculation.

subnetwork property

subnetwork: str

The subnetwork identifier as a hex string.

version property writable

version: int

The transaction version number.

__eq__

__eq__(other: Transaction) -> bool

__new__

__new__(version: int, inputs: Sequence[TransactionInput], outputs: Sequence[TransactionOutput], lock_time: int, subnetwork_id: Binary, gas: int, payload: Binary, mass: int) -> Transaction

Create a new transaction.

PARAMETER	DESCRIPTION
version	Transaction version number. TYPE: int
inputs	List of transaction inputs. TYPE: Sequence[TransactionInput]
outputs	List of transaction outputs. TYPE: Sequence[TransactionOutput]
lock_time	Lock time (block DAA score or timestamp). TYPE: int
subnetwork_id	Subnetwork identifier (hex string or bytes). TYPE: Binary
gas	Gas limit for smart contract execution. TYPE: int
payload	Optional transaction payload data. TYPE: Binary
mass	Transaction mass (for fee calculation). TYPE: int

RETURNS	DESCRIPTION
Transaction	A new Transaction instance. TYPE: Transaction

RAISES	DESCRIPTION
Exception	If the subnetwork_id is invalid or transaction creation fails.

__repr__

__repr__() -> str

The detailed string representation.

RETURNS	DESCRIPTION
str	The Transaction as a repr string. TYPE: str

addresses

addresses(network_type: str | NetworkType) -> list[Address]

Extract unique addresses from transaction inputs.

PARAMETER	DESCRIPTION
network_type	The network type to use for address encoding. TYPE: str | NetworkType

RETURNS	DESCRIPTION
list[Address]	list[Address]: List of unique addresses referenced by inputs.

finalize

finalize() -> Hash

Finalize the transaction and compute its ID.

RETURNS	DESCRIPTION
Hash	The computed transaction ID. TYPE: Hash

from_dict classmethod

from_dict(dict: dict) -> Transaction

Create a Transaction from a dictionary.

PARAMETER

DESCRIPTION

dict

Dictionary containing transaction fields with keys: - 'id' (str): Transaction ID as hex string - 'version' (int): Transaction version number - 'inputs' (list[dict]): List of input dictionaries - 'outputs' (list[dict]): List of output dictionaries - 'lockTime' (int): Lock time value - 'subnetworkId' (str): Subnetwork ID as hex string - 'gas' (int): Gas limit - 'payload' (str): Payload as hex string - 'mass' (int): Transaction mass TYPE: dict

RETURNS	DESCRIPTION
Transaction	A new Transaction instance. TYPE: Transaction

RAISES	DESCRIPTION
KeyError	If required keys are missing.
ValueError	If values are invalid.

is_coinbase

is_coinbase() -> bool

Check if this is a coinbase transaction.

RETURNS	DESCRIPTION
bool	True if this is a coinbase (mining reward) transaction. TYPE: bool

populate_genesis_covenants

populate_genesis_covenants(groups: Sequence[GenesisCovenantGroup]) -> None

Populate genesis covenant bindings for multiple output groups.

For each group, computes the covenant id from the authorizing input outpoint and the group's output list, then sets that binding on all listed outputs. All groups are validated before the transaction is mutated.

PARAMETER	DESCRIPTION
groups	The genesis covenant groups to populate. TYPE: Sequence[GenesisCovenantGroup]

RAISES	DESCRIPTION
Exception	If a group references a non-existent input or output, output indices are not strictly increasing, outputs overlap across groups, or a targeted output already has a covenant binding.

subnetwork_id

subnetwork_id(value: str) -> None

Set the subnetwork identifier.

PARAMETER	DESCRIPTION
value	The subnetwork ID as a hex string. TYPE: str

RAISES	DESCRIPTION
Exception	If the hex string is invalid or has incorrect length.

to_dict

to_dict() -> dict

Get a dictionary representation of the Transaction. Note that this creates a second separate object on the Python heap.

RETURNS	DESCRIPTION
dict	the Transaction in dictionary form. TYPE: dict