pyvast 2020.10.29

Python CLI wrapper for VAST - Visibility Across Space and Time

PyVAST - VAST Python CLI Wrapper

With pyvast we provide a very minimal python wrapper around the VAST command line interface. The wrapper features fluent method chaining and works asynchronously.

All VAST commands can be used with the wrapper. However, the wrapper does not implement any commands itself. It simply passes all received arguments to the vast binary. It is hence very easy to make mistakes in form of typos, given this minimalistic implementation. Please refer to the vast documentation for details about valid vast commands.

Installation

Use pip to install the package.

virtualenv --system-site-packages venv
source venv/bin/activate
pip install pyvast

Usage

Commands are simply chained via .-notation. Parameters can be passed as python keyword arguments. The following examples provide an overview of VAST commands and the analogous pyvast commands.

• Query for an IP address and return 10 results in JSON

  # CLI call
  vast export --max-event=10 json ':addr == 192.168.1.104'
  

  # python wrapper
  proc = await vast.export(max_events=10).json("192.167.1.102").exec()
  stdout, stderr = await proc.communicate()
  print(stdout)
  

• Import a Zeek log file

  # CLI call
  vast import zeek --read=/path/to/file
  

  # python wrapper
  proc = await vast.import_().zeek(read="/path/to/file").exec()
  stdout, stderr = await proc.communicate()
  print(stdout)
  

Module Parameterization

You can use PyVAST as Python module. After installing it via pip, simply import it normally in your Python application.

from pyvast import VAST

Once imported, there are three optional keyword arguments to instruct PyVAST with: binary, endpoint, and logger. The binary keyword defaults to "vast". In case the vast binary is not in your $PATH, set this to the actual path to the VAST binary. The endpoint keyword refers to the endpoint of the VAST node (e.g., localhost:42000). Lastly, use the logger keyword to provide a custom logging.logger object for your application.

See also the full example below.

Full Example

The following example shows a minimalistic working example with all required import statements.

#!/usr/bin/env python3

import asyncio
from pyvast import VAST

async def example():
  vast = VAST(binary="/opt/tenzir/bin/vast")
  await vast.test_connection()

  proc = await vast.export(max_events=10).json("192.168.1.103").exec()
  stdout, stderr = await proc.communicate()
  print(stdout)

asyncio.run(example())

See also the example folder for a demo using pyarrow for data export and a demo for continuous queries.

Testing

The tests are written with the python unittest library and its asynchronous analogon aiounittest. Install the requirements.txt first to run the tests.

pip install --user -r requirements.txt
python -m unittest discover .

Development

Use the setup.py for local installation of a development setup.

virtualenv --system-site-packages venv # create a virtual env
source venv/bin/activate
python setup.py develop # or python setup.py install