Python SDK for the Arcaflow workflow engine (WIP)

How this SDK works

In order to create an Arcaflow plugin, you must specify a schema for each step you want to support. This schema describes two things:

What your input parameters are and what their type is
What your output parameters are and what their type is

Note, that you can specify several possible outputs, depending on what the outcome of your plugin execution is. You should, however, never raise exceptions that bubble outside your plugin. If you do, your plugin will crash and Arcaflow will not be able to retrieve the result data, including the error, from it.

With the schema, the plugin can run in the following modes:

CLI mode, where a file with the data is loaded and the plugin is executed
GRPC mode (under development) where the plugin works in conjunction with the Arcaflow Engine to enable more complex workflows

For a detailed description please see the Arcalot website.

Requirements

In order to use this SDK you need at least Python 3.9.

Run the example plugin

In order to run the example plugin run the following steps:

Checkout this repository
Create a venv in the current directory with python3 -m venv $(pwd)/venv
Activate the venv by running source venv/bin/activate
Run pip install -r requirements.txt
Run ./example_plugin.py -f example.yaml

This should result in the following placeholder result being printed:

output_id: success
output_data:
  message: Hello, Arca Lot!

Generating a JSON schema file

Arcaflow plugins can generate their own JSON schema for both the input and the output schema. You can run the schema generation by calling:

./example_plugin.py --json-schema input
./example_plugin.py --json-schema output

If your plugin defines more than one step, you may need to pass the --step parameter.

Note: The Arcaflow schema system supports a few features that cannot be represented in JSON schema. The generated schema is for editor integration only.

Generating documentation

Checkout this repository
Create a venv in the current directory with python3 -m venv $(pwd)/venv
Activate the venv by running source venv/bin/activate
Run pip install -r requirements.txt
Run pip install sphinx
Run pip install sphinx-rtd-theme
Run sphinx-apidoc -o docs/ -f -a -e src/ --doc-project "Python SDK for Arcaflow"
Run make -C docs html

Developing your plugin

We have a detailed guide on developing Python plugins on the Arcalot website.

Release files for arcaflow-plugin-sdk 0.14.5

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for arcaflow-plugin-sdk 0.14.5
File	Size	Uploaded
arcaflow_plugin_sdk-0.14.5.tar.gz	61.4 kB	Jun 11, 2026	Details

Built distribution (wheel)

Table of built distributions (wheels) for arcaflow-plugin-sdk 0.14.5
File	Interpreter	ABI	Platform	Reset
arcaflow_plugin_sdk-0.14.5-py3-none-any.whl 65.5 kB Jun 11, 2026	Python 3	none	any	Details

Total release size: 126.8 kB

Release files / arcaflow_plugin_sdk-0.14.5.tar.gz

Download URL	arcaflow_plugin_sdk-0.14.5.tar.gz
Size	61.4 kB
Tags	Source
SHA-256 checksum How to use checksums	`c196ebce251f7381260eac5e9e42d876802df29855a28a2993e92cb77cc76f35`
BLAKE2b-256 checksum How to use checksums	`cb20ee281cadf352772b5fa046efe503e91c9e7591e36bd401bdea6491ef02d3`
Upload date	Jun 11, 2026
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/6.2.0 CPython/3.12.3`

Release files / arcaflow_plugin_sdk-0.14.5-py3-none-any.whl

Download URL	arcaflow_plugin_sdk-0.14.5-py3-none-any.whl
Size	65.5 kB
Tags	Python 3
SHA-256 checksum How to use checksums	`a83756bf058380abdc02eaa7b493af64301bf6e9c79da9192b6ead0c1b91fa14`
BLAKE2b-256 checksum How to use checksums	`df9b983ebd05993d9fd9fbe9c35966094fd0d85a7c6746215aa63f9a3b3c8bdb`
Upload date	Jun 11, 2026
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/6.2.0 CPython/3.12.3`