Daml Python bindings (formerly known as dazl)
Copyright (c) 2017-2024 Digital Asset (Switzerland) GmbH and/or its affiliates. All Rights Reserved.
SPDX-License-Identifier: Apache-2.0
Rich Python bindings for accessing Ledger API-based applications.
Documentation
The user documentation is available online here.
Installation
If you just want to use the library, you can install it locally with pip
:
pip install --user dazl
Requirements
- Python 3.6+
- Daml Connect
- Python gRPC libraries (1.32.0 or later) and Protobuf
WARNING: The next major version of dazl (v8.0.0) will require Python 3.8 or later.
Examples
All of the examples below assume you imported dazl
, and are running a ledger with the default scenario generated with daml new
.
Connect to the ledger and submit a single command:
import asyncio
import dazl
async def main():
async with dazl.connect(url='http://localhost:6865', act_as='Alice') as client:
contract = { 'issuer' : 'Alice', 'owner' : 'Alice', 'name' : 'hello world!' }
await client.create('Main:Asset', contract)
asyncio.run(main())
loop = asyncio.get_event_loop()
loop.run_until_complete(main())
Connect to the ledger as a single party, print all contracts, and close:
import asyncio
import dazl
from dazl.ledgerutil import ACS
async def main():
async with dazl.connect(url='http://localhost:6865', read_as='Alice') as conn:
async with ACS(conn, {"*": {}}) as acs:
snapshot = await acs.read()
print(snapshot)
asyncio.run(main())
loop = asyncio.get_event_loop()
loop.run_until_complete(main())
Building locally
You will need additional dependencies to build locally:
- GNU Make 4.3 or later
- Poetry for build/dependency management
Once you have these prerequisites in place:
make build
If you see errors about incompatible python versions, switch your environment to python3 using poetry env use python3
, for instance.
Tests
Tests in the Daml Python bindings are written using pytest. You can run them by doing:
make test
Support
The Daml Python bindings library is supported under the Daml Enterprise license. If you do not have a Daml Enterprise license and are in need of support, have questions or just want to engage in friendly conversation anything Daml, contact us on our Daml Community Forum.