py-geth 1.10.2

Run Go-Ethereum as a subprocess

# PyGeth

[](https://travis-ci.org/pipermerriam/py-geth) [](https://readthedocs.org/projects/py-geth/?badge=latest) [](https://pypi.python.org/pypi/py-geth) [](https://pypi.python.org/pypi/py-geth)

Python wrapper around running geth as a subprocess

# Dependency

This library requires the geth executable to be present.

# Quickstart

Installation

`bash pip install py-geth `

Or to install with gevent support

`bash pip install py-geth[gevent] `

And then enable gevent based threads by setting the environment variable GETH_THREADING_BACKEND=gevent.

To run geth connected to the mainnet

`python >>> from geth import LiveGethProcess >>> geth = LiveGethProcess() >>> geth.start() `

Or a private local chain for testing. These require you to give them a name.

`python >>> from geth import DevGethProcess >>> geth = DevGethProcess('testing') >>> geth.start() `

By default the DevGethProcess sets up test chains in the default datadir used by geth. If you would like to change the location for these test chains, you can specify an alternative base_dir.

`python >>> geth = DevGethProcess('testing', '/tmp/some-other-base-dir/') >>> geth.start() `

Each instance has a few convenient properties.

`python >>> geth.data_dir "~/.ethereum" >>> geth.rpc_port 8545 >>> geth.ipc_path "~/.ethereum/geth.ipc" >>> geth.accounts ['0xd3cda913deb6f67967b99d67acdfa1712c293601'] >>> geth.is_alive False >>> geth.is_running False >>> geth.is_stopped False >>> geth.start() >>> geth.is_alive True # indicates that the subprocess hasn't exited >>> geth.is_running True # indicates that `start()` has been called (but `stop()` hasn't) >>> geth.is_stopped False >>> geth.stop() >>> geth.is_alive False >>> geth.is_running False >>> geth.is_stopped True `

When testing it can be nice to see the logging output produced by the geth process. py-geth provides a mixin class that can be used to log the stdout and stderr output to a logfile.

`python >>> from geth import LoggingMixin, DevGethProcess >>> class MyGeth(LoggingMixin, DevGethProcess): ... pass >>> geth = MyGeth() >>> geth.start() `

All logs will be written to logfiles in ./logs/ in the current directory.

The underlying geth process can take additional time to open the RPC or IPC connections, as well as to start mining if it needs to generate the DAG. You can use the following interfaces to query whether these are ready.

`python >>> geth.is_rpc_ready True >>> geth.wait_for_rpc(timeout=30) # wait up to 30 seconds for the RPC connection to open >>> geth.is_ipc_ready True >>> geth.wait_for_ipc(timeout=30) # wait up to 30 seconds for the IPC socket to open >>> geth.is_dag_ready True >>> geth.is_mining True >>> geth.wait_for_dag(timeout=600) # wait up to 10 minutes for the DAG to generate. `

> The DAG functionality currently only applies to the DAG for epoch 0.

# Installing specific versions of geth

> This feature is experimental and subject to breaking changes.

Any of the following versions of geth can be installed using py-geth on the listed platforms.

• v1.5.6 (linux/osx)

• v1.5.7 (linux/osx)

• v1.5.8 (linux/osx)

• v1.5.9 (linux/osx)

• v1.6.0 (linux/osx)

• v1.6.1 (linux/osx)

• v1.6.2 (linux/osx)

• v1.6.3 (linux/osx)

• v1.6.4 (linux/osx)

• v1.6.5 (linux/osx)

• v1.6.6 (linux/osx)

• v1.6.7 (linux/osx)

• v1.7.0 (linux/osx)

• v1.7.2 (linux/osx)

Installation can be done via the command line:

`bash $ python -m geth.install v0.4.12 `

Or from python using the install_geth function.

`python >>> from geth import install_geth >>> install_geth('v1.7.0') `

The installed binary can be found in the $HOME/.py-geth directory, under your home directory. The v1.7.0 binary would be located at $HOME/.py-geth/geth-v1.7.0/bin/geth.

# About DevGethProcess

The DevGethProcess is designed to facilitate testing. In that regard, it is preconfigured as follows.

• A single account is created and allocated 1 billion ether.

• All APIs are enabled on both rpc and ipc interfaces.

• Account 0 is unlocked

• Networking is configured to not look for or connect to any peers.

• The networkid of 1234 is used.

• Verbosity is set to 5 (DEBUG)

• Mining is enabled with a single thread.

• The RPC interface tries to bind to 8545 but will find an open port if this port is not available.

• The DevP2P interface tries to bind to 30303 but will find an open port if this port is not available.

# Gotchas

If you are running with mining enabled (which is default for DevGethProcess then you will likely need to generate the DAG manually. If you do not, then it will auto-generate the first time you run the process and this takes a while.

To generate it manually:

`sh $ geth makedag 0 ~/.ethash `

This is especially important in CI environments like Travis-CI where your process will likely timeout during generation.