Python backend for node editor-like graph-based processing


Keywords
flow, python, visual-scripting
Licenses
LGPL-3.0/GPL-3.0+
Install
pip install ryvencore==0.5.0

Documentation

drawing

An experimental Python library for graph-based processing, designed for flow-based/node-based visual scripting editors. It is the backbone of the Ryven project, but it can very much be used in other contexts as well.

While ryvencore is written purely in Python, it is very lightweight and highly compatible. It can be compiled with Cython, see the setup_cython.py file. The performance seems comparable so far, but the code hasn't been optimized for Cython yet, so there might be a lot of potential. Please consider contributing. ryvencore also seems compatible with most Python ports to WebAssembly, even the Cython compiled ryvencore.

Installation

pip install ryvencore

or from sources:

git clone https://github.com/leon-thomm/ryvencore
cd ryvencore
pip install .

Usage

As an experimental library, the API is not fully stable and small breaking changes over time should be expected. Generally, the API is defined by what is included in the docs.

Examples

loading a project e.g. exported from Ryven

import ryvencore as rc
import json
import sys

if __name__ == '__main__':
    # project file path
    fpath = sys.args[1]

    # read project file
    with open(fpath, 'r') as f:
        project: dict = json.loads(f.read())

    # run ryvencore
    session = rc.Session()
    session.load(project)

    # access the first flow
    f = session.flows[0]
    
    # and the last node that was created
    my_node = f.nodes[-1]

    # and execute it
    my_node.update()

Features

The main features include

  • load & save from and into JSON
  • a simple and powerful nodes system which lets you do anything, simple and unrestricted
  • data and exec flow support - unlike lots of other solutions out there, ryvencore supports exec flows
  • variables system with subscribe and update mechanism to build nodes that automatically adapt to change of data
  • built-in logging based on python's logging module
  • actions system for nodes (WIP)

Licensing

ryvencore is licensed under the LGPL License.