dynamic serializer resolving in flask rest plus based on serialized value in another field

using polymorphism should do the trick.

class Action(base):    id = Column(Integer, primary_key=True)    action_type = Column(Enum(SubscriptionActionType, inherit_schema=True), nullable=False)    parameters = Column(JSONB)    __mapper_args__ = {        'polymorphic_on' : action_type    }class ActionOne(Action):    __mapper_args__ = {        'polymorphic_identity': 'action_one'    }class ActionTwo(Action):    __mapper_args__ = {        'polymorphic_identity': 'action_two'    }

then using fields.Polymorph

mapping = {    ActionOne: action_one_serializer,    ActionTwo: action_two_serializer,}fields = api.model('Action', {    owner: fields.Polymorph(mapping)})

and providing definitions for serializers using api.inherit like this:

base_action_serializer = api.model('BaseAction', {    'id': fields.Integer(readonly=True),    'action_type': fields.String(discriminator=True)})action_one_serializer = api.inherit('ActionOne', parent, {    'extra_one': fields.String(attribute('parameters.extraOne'))})action_two_serializer = api.inherit('ActionTwo', parent, {    'extra_two': fields.String(attribute('parameters.extraTwo'))})