gistfile1.py

>>> from schematics.models import Model
>>> from schematics.types.base import StringType, DateTimeType, IntType, BooleanType
>>> from schematics.types.compound import ListType, ModelType
>>> 
>>> class ProtoStep(Model):
...     step_type = StringType(required=True) # enum type?
...     deadline = DateTimeType()
... 
>>> class DocumentStep(ProtoStep):
...     doc_name = StringType()
...     responsible = IntType()
... 
>>> class ApprovalStep(ProtoStep):
...     include_subparts = BooleanType(default=False)
...     responsible_list = ListType(IntType(), required=True)
... 
>>> class WorkflowPayload(Model):
...     steps = ListType([ModelType(DocumentStep),
...                       ModelType(ApprovalStep)], required=True)
... 
>>> x = {
...     "steps": [
...         {
...             "step_type": "DU",
...             "deadline": "2013-02-02T00:00:00Z",
...             "doc_name": "NDA document",
...             "responsible": 3
...         },
...         {
...             "step_type": "AP",
...             "include_subparts": True,
...             "responsible_list": [2, 4]
...         }
...     ]
... }
>>> wp = WorkflowPayload(**x)
>>> wp.steps
[<DocumentStep: DocumentStep object>, <ApprovalStep: ApprovalStep object>]
>>> wp.steps[0].step_type
'DU'
>>> wp.steps[0].doc_name
'NDA document'