BPMN DMN (bpmn_dmn)

A library to execute BPMN Workflows and DMN Decision Tables.

Introduction

This package uses SpiffWorkflow to execute the DBPM workflow. I wrote my own DMN engine to execute DMN Decision Tables. I used the Camunda Modeleler to create all my files.

The bpmn_dmn package contains 3 main modules:

• bpmn to execute BPMN Workflow Charts by using an xml file on the disc

• dmn to execute DMN Decision Tables by using an xml file on the disc

• bpmn_dmn to execute BPMN Workflow Charts that includes DMN Decision Tables as business tasks

Doc and Modeler

• Camunda BPMN Doc
• Camunda DMN Doc
• Camunda Modeler

Usage

Execute bpmn Workflow Charts (See bpmn/tests):

Use the BPMNXMLWorkflowRunner class to execute xml files (based on SpiffWorkflow)

Constructor: path, workflowProcessID=None, debug=False, **kwargs

Basic Example:

from bpmn_dmn.bpmn import BPMNXMLWorkflowRunner

class Lorder:
    def __init__(self, status, printedfl):
        self.status = status
        self.printedfl = printedfl

runner = BPMNXMLWorkflowRunner('exclusive_gateway_two_if_else.bpmn', debug=True)
runner.start(lorder=Lorder(2, True))
res = runner.getEndEventName()
print(res)

I want more:

In my unit tests I currently only used Exclusive Gateways. But there is MUCH more. Please see the SpiffWorkflow BPMN UnitTests.

All of them should work in my library too, since I simply wrote a base Class that wraps the xml packager and some more small features.

Execute bpmn Workflow Charts that includes DMN Decision Tables (See bpmn_dmn/tests):

Use the BPMNDMNXMLWorkflowRunner class to execute xml files

Constructor: path, workflowProcessID=None, debugLog='INFO', debug=False, **kwargs

Basic Example:

from bpmn_dmn.bpmn_dmn import BPMNDMNXMLWorkflowRunner

runner = BPMNDMNXMLWorkflowRunner('ExclusiveGatewayIfElseAndDecision.bpmn', debugLog='DEBUG', debug=True)
runner.start(x=3)

res = runner.getEndEventName()
print(res)

Use my own script engine:

from bpmn_dmn.bpmn import BPMNXMLWorkflowRunner

from SpiffWorkflow.bpmn.BpmnScriptEngine import BpmnScriptEngine

class LXScriptEngine(BpmnScriptEngine):
    @staticmethod
    def lxs(fctName, lorder):
        print('lxs', fctName, lorder)

        if fctName == 'checkPatientOrder':
            return lorder.patientOrder
        else:
            raise NotImplementedError(fctName)

    def _eval(self, task, expression, **kwargs):
        locals().update(kwargs)
        locals().update({'lxs': LXScriptEngine.lxs})
        return eval(expression)

class LXS_BPMNXMLWorkflowRunner(BPMNXMLWorkflowRunner):
    def __init__(self, *args, **kwargs):
        super(LXS_BPMNXMLWorkflowRunner, self).__init__(*args, **kwargs, script_engine=LXScriptEngine())

class Lorder:
    def __init__(self, status, printedfl):
        self.status = status
        self.printedfl = printedfl

runner = LXS_BPMNXMLWorkflowRunner('exclusive_gateway_two_if_else.bpmn', debugLog='DEBUG', debug=True)
runner.start(lorder=Lorder(2, True))
res = runner.getEndEventName()
print(res)

Execute dmn Decision Tables (See dmn/tests):

Use the DMNDecisionRunner class to execute xml files

Constructor: path, debug='INFO'

Basic Example:

from bpmn_dmn.dmn import DMNDecisionRunner

runner = DMNDecisionRunner('string_integer_decision.dmn', debug='DEBUG')
res = self.runner.decide('m', 30)
print(res)

How to install

From github

pip install git+https://github.com/labsolutionlu/bpmn_dmn.git or pip install git+https://github.com/labsolutionlu/[email protected]

From pypi pip install bpmn-dmn

Authors

• Denny Weinberg - Initial work - DennyWeinberg

License

This project is licensed under the MIT License - see the LICENSE.md file for details

TODOs

• Log improvements
• Test other unit tests from SpiffWorkflow Source
• Implement all differnt modes that are available for DMN tables