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 block chain
Runs smart contracts on the block chain in a python virtual machine
Very basic Wallet functionality (Not fully tested, please do not use on mainnet)

What will it do

Full python RPC client
Compile smart contracts written python and deploy to blockchain
Full smart contract debugging and inspection

Get Help or give help

Open a new issue if you encounter a problem.
Or ping @localhuman on the NEO Slack.
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.

OSX:

brew install leveldb

ubuntu/debian

apt-get -s install libleveldb-dev

Centos/Redhat/Fedora

This is a bit more tricky...

yum -y install development tools python35 python35-devel python35-pip readline-devel leveldb-devel libffi-devel

You may need to enable the epel repo for the leveldb-devel package, which you can do by editing /etc/yum.repos.d/epel.repo.

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.

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

python3 -m venv venv
source venv/bin/activate

Then install requirements

pip install -r requirements.txt

Installing on OSX

If you're having an issue similar to this:

    from ._plyvel import (  # noqa
    ImportError: dlopen(neo-python/venv/lib/python3.5/site-packages/plyvel/_plyvel.cpython-35m-darwin.so, 2): Symbol not found: __ZN7leveldb2DB4OpenERKNS_7Options
    ERKSsPPS0_
    Referenced from: neo-python/venv/lib/python3.5/site-packages/plyvel/_plyvel.cpython-35m-darwin.so
    Expected in: flat namespace

You may need to uninstall plyvel (python libleveldb library), and reinstall with the following cflags

pip uninstall plyvel
CFLAGS='-mmacosx-version-min=10.7 -stdlib=libc++' pip install --no-use-wheel plyvel --no-cache-dir

Moreover, this pip installation must see the leveldb header file db.h. You may need to add flags similar to the following to the installation command

--global-option=build_ext
--global-option="-I/usr/local/Cellar/leveldb/1.20_2/include/"
--global-option="-L/usr/local/lib"

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> show 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> show 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

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

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 command

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.

python -m unittest discover neo

To run tests with coverage, use the following

coverage run -m unittest discover neo

After that, you can generate a command line coverage report use the following:

coverage report -m --omit=venv/*

License

Open-source Apache 2.0.
Main author is @localhuman.

paulmadore/neo-python