This Python3 library provides an easy interface to the bitcoin data structures. This is based on https://github.com/petertodd/python-bitcoinlib, but is focused only on providing the tools to build, manipulate and sign bitcoin transactions, and related data structures. Network-related code that deals with sending and receiving data from and to bitcoin nodes is removed. Bech32 segwit address support and RFC6979 signing with libsecp256k1 are added.
"The Swiss Army Knife of the Bitcoin protocol." - Wladimir J. van der Laan
sudo apt-get install libssl-dev
The RPC interface, bitcointx.rpc, is designed to work with Bitcoin Core v0.16.0.
Older versions may work but there do exist some incompatibilities.
Everything consensus critical is found in the modules under bitcointx.core. This rule is followed pretty strictly, for instance chain parameters are split into consensus critical and non-consensus-critical.
bitcointx.core - Basic core definitions, datastructures, and
(context-independent) validation
bitcointx.core.key - ECC pubkeys
bitcointx.core.script - Scripts and opcodes
bitcointx.core.scripteval - Script evaluation/verification
bitcointx.core.serialize - Serialization
In the future the bitcointx.core may use the Satoshi sourcecode directly as a library. Non-consensus critical modules include the following:
bitcointx - Chain selection
bitcointx.base58 - Base58 encoding
bitcointx.rpc - Bitcoin Core RPC interface support (may also be stripped later)
bitcointx.wallet - Wallet-related code, currently Bitcoin address and
private key support
Effort has been made to follow the Satoshi source relatively closely, for instance Python code and classes that duplicate the functionality of corresponding Satoshi C++ code uses the same naming conventions: CTransaction, CBlockHeader, nValue etc. Otherwise Python naming conventions are followed.
Like the Bitcoin Core codebase CTransaction is immutable and CMutableTransaction is mutable; unlike the Bitcoin Core codebase this distinction also applies to COutPoint, CTxIn, CTxOut, and CBlock.
Rather confusingly Bitcoin Core shows transaction and block hashes as little-endian hex rather than the big-endian the rest of the world uses for SHA256. python-bitcointx provides the convenience functions x() and lx() in bitcointx.core to convert from big-endian and little-endian hex to raw bytes to accomodate this. In addition see b2x() and b2lx() for conversion from bytes to big/little-endian hex.
While not always good style, it's often convenient for quick scripts if
import * can be used. To support that all the modules have __all__ defined
appropriately.
See examples/ directory. For instance this example creates a transaction
spending a pay-to-script-hash transaction output:
$ PYTHONPATH=. examples/spend-pay-to-script-hash-txout.py
<hex-encoded transaction>
Do the following:
import bitcointx
bitcointx.SelectParams(NAME)
Where NAME is one of 'testnet', 'mainnet', or 'regtest'. The chain currently selected is a global variable that changes behavior everywhere, just like in the Satoshi codebase.
It is possible to use libsecp256k1 for signing, but it have to be enabled manually, at this time.
The relevant functions are is_libsec256k1_available() and use_libsecp256k1_for_signing(do_use)
NOTE: libsecp256k1 will likely become default and required for signing, and this functions will be removed then.
refer to Test_RFC6979() in bitcointx/tests/test_wallet.py for example of usage.
Under bitcointx/tests using test data from Bitcoin Core. To run them:
python -m unittest discover && python3 -m unittest discover
Please run the tests on both Python2 and Python3 for your pull-reqs!
Alternately, if Tox (see https://tox.readthedocs.org/) is available on your system, you can run unit tests for multiple Python versions:
./runtests.sh
Currently, the following implementations are tried (any not installed are skipped):
* CPython 3.3
* CPython 3.4
* CPython 3.5
* PyPy
* PyPy3
HTML coverage reports can then be found in the htmlcov/ subdirectory.
Sphinx documentation is in the "doc" subdirectory. Run "make help" from there to see how to build. You will need the Python "sphinx" package installed.
Currently this is just API documentation generated from the code and docstrings. Higher level written docs would be useful, perhaps starting with much of this README. Pages are written in reStructuredText and linked from index.rst.