Server configuration

ewoksserver can be configured by declaration the following variables in a Python file:

• RESOURCE_DIRECTORY (string): defines the path to the resource folder where workflows, tasks, icons are stored. Equivalent to the --dir/-d command line argument.

• EWOKS_EXECUTION (dict): Configuration of ewoks handlers. See the Ewoks events section below.

• CELERY (dict): Configuration of Celery to allow launching workflows in ewoks workers.

Example:

# /tmp/config.py

RESOURCE_DIRECTORY = "/path/to/resource/directory/"

EWOKS_EXECUTION = {"handlers": ...}

CELERY = {"broker_url":...}

The path to configuration file can then be passed through the --config command line argument:

ewoks-server --config /tmp/config.py

The environment variable EWOKSSERVER_SETTINGS can be used instead:

export EWOKSSERVER_SETTINGS=/tmp/config.py
ewoks-server

Ewoks events

When executing workflows, ewoksserver can send ewoks events through a Socket.IO connection. Events are stored in a database by ewoksjob which needs further configuration.

ewoksjob supports redis and sql as databases. So first, one of these must be installed (here we choose sql):

pip install ewoksjob[sql]

Then, in the configuration of ewoks-server, the EWOKS_EXECUTION parameter must define the appropriate “handlers”:

# /tmp/config.py

EWOKS_EXECUTION = {
    "handlers": [
        {
            "class": "ewokscore.events.handlers.Sqlite3EwoksEventHandler",
            "arguments": [
                {
                    "name": "uri",
                    "value": "file:/any/path/ewoks_events.db",
                }
            ],
        }
    ]
}

If the server displays on start-up that the EWOKS_EXECUTION parameter has “handlers”, it means that ewoks events are ready to be sent when executing workflows:

$ ewoks-server -c /tmp/config.py

<...>

EWOKS_EXECUTION:
{'handlers': [{'arguments': [{'name': 'uri',
                            'value': 'file:/home/huder/ewoksserver_resources/ewoks_events.db'}],
            'class': 'ewokscore.events.handlers.Sqlite3EwoksEventHandler'}]}

<...>