stevenjack / neo-python

Python Node and SDK for the NEO blockchain

neo-python

Python Node and SDK for the NEO blockchain.

Overview

What does it currently do

• This project aims to be a full port of the original C# NEO project
• Run a Python based P2P node
• Interactive CLI for configuring node and inspecting blockchain
• Runs smart contracts on the blockchain in a Python virtual machine
• Very basic Wallet functionality (not fully tested, please do not use on mainnet)
• NEP2 and NEP5 compliant wallet functionality
• RPC Client
• Runtime.Log and Runtime.Notify event monitoring

What will it do

• RPC server
• Consensus nodes
• More robust smart contract debugging and inspection

Documentation

• Installation, Configuration, and usage documentation available at Read The Docs

Get Help or give help

• Open a new issue if you encounter a problem.
• Or ping @localhuman or @metachris on the NEO Discord.
• Pull requests welcome. You can help with wallet functionality, writing tests or documentation, or on any other feature you deem awesome. All successful pull requests will be rewarded with one photo of a cat or kitten.

Getting started

You will need to install the libleveldb library. Install Python 3.5 to make sure you don't run into any issues with your version of Python being different than the current maintainer's version. Note that Python 3.6 is not currently supported due to incompatibilities with the byteplay module.

We have published a Youtube video to help get you started with this library. There are other videos under the CityOfZion Youtube channel.

OSX:

brew install leveldb

Ubuntu/Debian

apt-get install libleveldb-dev python3.5-dev python3-pip python3-venv libssl-dev g++

Centos/Redhat/Fedora

This is a bit more tricky...

# Install Python 3.5:
yum install -y centos-release-scl
yum install -y rh-python35
scl enable rh-python35 bash

# Install dependencies:
yum install -y epel-release
yum install -y readline-devel leveldb-devel libffi-devel gcc-c++ redhat-rpm-config gcc python-devel openssl-devel

For all of these, make sure that the Chains directory in your project has the proper write permissions

Windows

Not sure. Installing the Python package plyvel seems to require C++ compiler support tied to Visual Studio and libraries.

---

Virtual Environment

Now navigate into the project, make a Python 3 virtual environment and activate it via

python3.5 -m venv venv
source venv/bin/activate

Then install the requirements:

pip install -U setuptools pip wheel
pip install -e .

Running

After installing requirements and activating your environment, there is an easy to use prompt.py file for you to run the node as well as some basic interactivity

python prompt.py
NEO cli. Type 'help' to get started

neo> state
Progress: 1054913 / 1237188

neo>

You can query for a block in the current server by hash or by block index:

python prompt.py
NEO cli. Type 'help' to get started

neo> block 122235
{
    "index": 122235,
    "script": "",
    "merkleroot": "1d5a895ea34509a83becb5d2f9391018a3f59d670d94a2c3f8deb509a07464bd",
    "previousblockhash": "98ae05cb68ab857659cc6c8379eb7ba68b57ef1f5317904c295341d82d0a1713",
    "tx": [
        "1d5a895ea34509a83becb5d2f9391018a3f59d670d94a2c3f8deb509a07464bd"
    ],
    "version": 0,
    "time": 1479110368,
    "hash": "74671375033f506325ef08d35632f74083cca564dc7ea6444c94d3b9dec3f61b",
    "consensus data": 16070047272025254767,
    "next_consensus": "59e75d652b5d3827bf04c165bbe9ef95cca4bf55"
}
neo>

Available Wallet commands

help

create wallet {wallet_path}
open wallet {wallet_path}

wallet { verbose } { rebuild } {rebuild BLOCK_HEIGHT}
export wif { ADDRESS }
import wif { WIF }

send { ASSET_ID } { ADDRESS } { AMOUNT }

Extra notes

To run the prompt on mainnet, you can use the cli argument -m:

$ python prompt.py -h
usage: prompt.py [-h] [-m] [-p] [-c CONFIG] [-t {dark,light}] [--version]

optional arguments:
  -h, --help            show this help message and exit
  -m, --mainnet         Use MainNet instead of the default TestNet
  -p, --privnet         Use PrivNet instead of the default TestNet
  -c CONFIG, --config CONFIG
                        Use a specific config file
  -t {dark,light}, --set-default-theme {dark,light}
                        Set the default theme to be loaded from the config
                        file. Default: 'dark'
  --version             show program's version number and exit

On OSX, if you would like to run the process in the background, even when your computer is sleeping, you can use the built in caffeinate command

caffeinate python prompt.py

Logging

Currently, prompt.py logs to prompt.log

Tests

Tests are important. Currently there are not enough, but we are working on that. You can start them by running this commands:

make test
make coverage

Note that some of the unit tests use a giant blockchain fixture database ( around 800mb ). This file is not kept in the repo.

When running tests the first time, the test setup will try to download the file and extract it to the proper directory. Long story short: the first time you run your tests, it will take a while to download those fixtures. After that it should be pretty quick.

Useful commands

make lint
make test
make coverage
make docs

Updating the version number and releasing new versions of neo-python

(Only for admins)

This is a checklist for releasing a new version:

.. code-block:: console

# In case you want to increase the version number again (eg. scope changed from patch to minor):
bumpversion --no-tag patch|minor|major

# Update ``CHANGELOG.md`` and ``docs/source/changelog.rst`` with the new version number and the changes and commit this
vi CHANGELOG.md docs/source/changelog.rst
git commit -m "Updated Changelogs" CHANGELOG.md docs/source/changelog.rst

# Set the release version number and create the tag
bumpversion release

# Increase patch number and add `-dev`
bumpversion --no-tag patch

# Push to GitHub, which also updates the PyPI package
git push && git push --tags

Troubleshooting

If you encounter any problems, please take a look at the installation section in the docs, and if that doesn't help open an issue. We'll try to help.

License

• Open-source MIT.
• Main author is @localhuman.

Donations

Accepted at ATEMNPSjRVvsXmaJW4ZYJBSVuJ6uR2mjQU