Example start event

start_event.py

from SpiffWorkflow.bpmn.serializer.workflow import BpmnWorkflowSerializer
from SpiffWorkflow.bpmn.workflow import BpmnWorkflow
from SpiffWorkflow.spiff.parser.process import BpmnValidator, SpiffBpmnParser
from SpiffWorkflow.spiff.serializer.config import SPIFF_CONFIG

SERIALIZER_VERSION = "3"

BPMN = """<?xml version="1.0" encoding="UTF-8"?>
<bpmn:definitions xmlns:bpmn="http://www.omg.org/spec/BPMN/20100524/MODEL" xmlns:bpmndi="http://www.omg.org/spec/BPMN/20100524/DI" xmlns:dc="http://www.omg.org/spec/DD/20100524/DC" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:di="http://www.omg.org/spec/DD/20100524/DI" xmlns:modeler="http://camunda.org/schema/modeler/1.0" id="Definitions_1qnx3d3" targetNamespace="http://bpmn.io/schema/bpmn" exporter="Camunda Modeler" exporterVersion="5.0.0" modeler:executionPlatform="Camunda Platform" modeler:executionPlatformVersion="7.17.0">
  <bpmn:process id="Process_YzA9iBf" isExecutable="true">
    <bpmn:sequenceFlow id="Flow_1trxk8d" sourceRef="StartEvent_1" targetRef="Activity_1n1t0x1" />
    <bpmn:endEvent id="Event_1e0ho54">
      <bpmn:incoming>Flow_1w46fh7</bpmn:incoming>
    </bpmn:endEvent>
    <bpmn:sequenceFlow id="Flow_1w46fh7" sourceRef="Activity_1n1t0x1" targetRef="Event_1e0ho54" />
    <bpmn:manualTask id="Activity_1n1t0x1" name="A">
      <bpmn:incoming>Flow_1trxk8d</bpmn:incoming>
      <bpmn:outgoing>Flow_1w46fh7</bpmn:outgoing>
    </bpmn:manualTask>
    <bpmn:startEvent id="StartEvent_1">
      <bpmn:outgoing>Flow_1trxk8d</bpmn:outgoing>
    </bpmn:startEvent>
  </bpmn:process>
  <bpmndi:BPMNDiagram id="BPMNDiagram_1">
    <bpmndi:BPMNPlane id="BPMNPlane_1" bpmnElement="Process_YzA9iBf">
      <bpmndi:BPMNShape id="Event_1e0ho54_di" bpmnElement="Event_1e0ho54">
        <dc:Bounds x="432" y="172" width="36" height="36" />
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape id="Activity_02kmga4_di" bpmnElement="Activity_1n1t0x1">
        <dc:Bounds x="270" y="150" width="100" height="80" />
      </bpmndi:BPMNShape>
      <bpmndi:BPMNShape id="Event_1hpbbha_di" bpmnElement="StartEvent_1">
        <dc:Bounds x="179" y="172" width="36" height="36" />
      </bpmndi:BPMNShape>
      <bpmndi:BPMNEdge id="Flow_1trxk8d_di" bpmnElement="Flow_1trxk8d">
        <di:waypoint x="215" y="190" />
        <di:waypoint x="270" y="190" />
      </bpmndi:BPMNEdge>
      <bpmndi:BPMNEdge id="Flow_1w46fh7_di" bpmnElement="Flow_1w46fh7">
        <di:waypoint x="370" y="190" />
        <di:waypoint x="432" y="190" />
      </bpmndi:BPMNEdge>
    </bpmndi:BPMNPlane>
  </bpmndi:BPMNDiagram>
</bpmn:definitions>
"""

wf_spec_converter = BpmnWorkflowSerializer.configure(SPIFF_CONFIG)
parser = SpiffBpmnParser(validator=BpmnValidator())
serializer = BpmnWorkflowSerializer(wf_spec_converter, version=SERIALIZER_VERSION)

parser.add_bpmn_str(BPMN.encode("utf-8"))

process_id = parser.get_process_ids()[0]
spec = parser.get_spec(process_id)
workflow = BpmnWorkflow(spec)

print(workflow.get_dump())