mkoura/cardano-clusterlib-py

Python wrapper for cardano-cli for working with cardano cluster

README for cardano-clusterlib

Python wrapper for cardano-cli for working with cardano cluster. It supports all cardano-cli commands (except parts of genesis and governance).

The library is used for development of cardano-node system tests.

Installation

# create and activate virtual env
$ python3 -m venv .env
$ . .env/bin/activate
# install cardano-clusterlib from PyPI
$ pip install cardano-clusterlib
# - OR - install cardano-clusterlib in development mode together with dev requirements
$ make install

Usage

The library needs working cardano-cli (the command is available on PATH, cardano-node is running, CARDANO_NODE_SOCKET_PATH is set). In state_dir it expects "shelley/genesis.json".

# instantiate `ClusterLib`
cluster = clusterlib.ClusterLib(state_dir="path/to/cluster/state_dir")

On custom testnets that were started in Byron era, you might need to specify a slots offset between Byron epochs and Shelley epochs. The "slots_offset" is a difference between number of slots in Byron epochs and in the same number of Shelley epochs.

E.g. for a testnet with parameters

• 100 slots per epoch in Byron era
• 1000 slots per epoch in Shelley era
• two epochs in Byron era before forking to Shelley

The offset will be 2 * (1000 - 100) = 1800.

cluster = clusterlib.ClusterLib(state_dir="path/to/cluster/state_dir", slots_offset=1800)

Transfer funds

from cardano_clusterlib import clusterlib

# instantiate `ClusterLib`
cluster = clusterlib.ClusterLib(state_dir="path/to/cluster/state_dir")

src_address = "addr_test1vpst87uzwafqkxumyf446zr2jsyn44cfpu9fe8yqanyuh6glj2hkl"
src_skey_file = "/path/to/skey"

dst_addr = cluster.g_address.gen_payment_addr_and_keys(name="destination_address")
amount_lovelace = 10_000_000  # 10 ADA

# specify where to send funds and amounts to send
txouts = [clusterlib.TxOut(address=dst_addr.address, amount=amount_lovelace)]

# provide keys needed for signing the transaction
tx_files = clusterlib.TxFiles(signing_key_files=[src_skey_file])

# build, sign and submit the transaction
tx_raw_output = cluster.g_transaction.send_tx(
    src_address=src_address,
    tx_name="send_funds",
    txouts=txouts,
    tx_files=tx_files,
)

# check that the funds were received
cluster.g_query.get_utxo(dst_addr.address)

Lock and redeem funds with Plutus script

from cardano_clusterlib import clusterlib

# instantiate `ClusterLib`
cluster = clusterlib.ClusterLib(state_dir="path/to/cluster/state_dir", tx_era="babbage")

# source address - for funding
src_address = "addr_test1vpst87uzwafqkxumyf446zr2jsyn44cfpu9fe8yqanyuh6glj2hkl"
src_skey_file = "/path/to/skey"

# destination address - for redeeming
dst_addr = cluster.g_address.gen_payment_addr_and_keys(name="destination_address")

amount_fund = 10_000_000  # 10 ADA
amount_redeem = 5_000_000  # 5 ADA

# get address of the Plutus script
script_address = cluster.g_address.gen_payment_addr(
    addr_name="script_address", payment_script_file="path/to/script.plutus"
)

# create a Tx output with a datum hash at the script address

# provide keys needed for signing the transaction
tx_files_fund = clusterlib.TxFiles(signing_key_files=[src_skey_file])

# get datum hash
datum_hash = cluster.g_transaction.get_hash_script_data(script_data_file="path/to/file.datum")

# specify Tx outputs for script address and collateral
txouts_fund = [
    clusterlib.TxOut(address=script_address, amount=amount_fund, datum_hash=datum_hash),
    # for collateral
    clusterlib.TxOut(address=dst_addr.address, amount=2_000_000),
]

# build and submit the Tx
tx_output_fund = cluster.g_transaction.build_tx(
    src_address=src_address,
    tx_name="fund_script_address",
    tx_files=tx_files_fund,
    txouts=txouts_fund,
    fee_buffer=2_000_000,
)
tx_signed_fund = cluster.g_transaction.sign_tx(
    tx_body_file=tx_output_fund.out_file,
    signing_key_files=tx_files_fund.signing_key_files,
    tx_name="fund_script_address",
)
cluster.g_transaction.submit_tx(tx_file=tx_signed_fund, txins=tx_output_fund.txins)

# get newly created UTxOs
fund_utxos = cluster.g_query.get_utxo(tx_raw_output=tx_output_fund)
script_utxos = clusterlib.filter_utxos(utxos=fund_utxos, address=script_address)
collateral_utxos = clusterlib.filter_utxos(utxos=fund_utxos, address=dst_addr.address)

# redeem the locked UTxO

plutus_txins = [
    clusterlib.ScriptTxIn(
        txins=script_utxos,
        script_file="path/to/script.plutus",
        collaterals=collateral_utxos,
        datum_file="path/to/file.datum",
        redeemer_file="path/to/file.redeemer",
    )
]

tx_files_redeem = clusterlib.TxFiles(signing_key_files=[dst_addr.skey_file])

txouts_redeem = [
    clusterlib.TxOut(address=dst_addr.address, amount=amount_redeem),
]

# The entire locked UTxO will be spent and fees will be covered from the locked UTxO.
# One UTxO with "amount_redeem" amount will be created on "destination address".
# Second UTxO with change will be created on "destination address".
tx_output_redeem = cluster.g_transaction.build_tx(
    src_address=src_address,  # this will not be used, because txins (`script_txins`) are specified explicitly
    tx_name="redeem_funds",
    tx_files=tx_files_redeem,
    txouts=txouts_redeem,
    script_txins=plutus_txins,
    change_address=dst_addr.address,
)
tx_signed_redeem = cluster.g_transaction.sign_tx(
    tx_body_file=tx_output_redeem.out_file,
    signing_key_files=tx_files_redeem.signing_key_files,
    tx_name="redeem_funds",
)
cluster.g_transaction.submit_tx(tx_file=tx_signed_redeem, txins=tx_output_fund.txins)

More examples

See cardano-node-tests for more examples, e.g. minting new tokens or minting new tokens with Plutus

Source Documentation

https://cardano-clusterlib-py.readthedocs.io/en/latest/cardano_clusterlib.html

Contributing

Install this package and its dependencies as described above.

Run pre-commit install to set up the git hook scripts that will check you changes before every commit. Alternatively run make lint manually before pushing your changes.

Follow the Google Python Style Guide, with the exception that formatting is handled automatically by Black (through pre-commit command).