ethgasstation

an adaptive gas price oracle for the ethereum blockchain

This is the backend for ethgasstation, written in Python 3. This python script is designed to monitor a local Geth or Parity node. It will record data about pending and mined transactions, including the transactions in your node's transaction pool. Its main purpose is to generate adaptive gas price estimates that enable you to know what gas price to use depending on your confirmation time needs. It generates these estimates based on miner policy estimates as well as the number of transactions in the txpool and the gas offered by the transaction.

The basic strategy is to use statistical modelling to predict confirmation times at all gas prices from 0-100 gwei at the current state of the txpool and minimum gas prices accepted in blocks over the last 200 blocks. Then, it selects the gas price that gives the desired confirmation time assuming standard gas offered (higher than 1m gas is slower).

Installation and Prerequisites

ethgasstation requires Python 3, MySQL/MariaDB, and Geth/Parity. You will need to modify settings.conf for your specific environment; some (insecure) defaults are set to get you up and running.

The oracle outputs JSON files. These files are stored in the output directory specified by the settings.conf file. You may output these JSON strings to files by setting json.output_type to file and json.output_location to a filepath, such as:

[json]
    output_type = file
    output_location = ./json

or you may set json.output_type to Redis and give a redis connection string:

[json]
    output_type = redis
    output_location = http://localhost:6379

Redis password authentication is also supported by adding it to the output location string, e.g. http://:password@localhost:6379/.

Usage

To run the script as is on bare metal or a VM, manually:

0. Edit settings.conf and install to an allowed directory.
1. Install requirements using pip3 install -r requirements.txt
2. Run ./ethgasstation.py or python3 ethgasstation.py.

If you are running a frontend to ETH Gas Station, use the --generate-report flag to generate detailed JSON reports for front-end or API consumption.

Docker

It is also possible to run the oracle as a Docker container.

1. Change the settings and environment variables in settings.docker.conf and .env
2. Copy/edit the environment variables to match: cp .env.example .env
3. Run docker-compose up

In the Docker service, the Python script will dump data to JSON on Redis. You may need to update your settings.conf to the internal hostnames available for MariaDB, Redis, and geth or parity, respectively within your infrastructure.

Deployment

Ensure latest urllib3 is installed

pip install git+https://github.com/shazow/urllib3

or if that doesn't help upgrade requirements.txt, then

cd /usr/local/SettleFinance/ethgasstation-backend pip install -r requirements.txt

pip install --upgrade urllib3