def setup_workflow_graph(model, nodes=None, edges=None, force=True, **kwargs):
"""
created a new workflow graph if a graph with the same structure does not already exists.
old graphs will loose their auto_start=True flag.
"""
if isinstance(edges, dict):
edges = edges.items()
try:
graph, created = Graph.objects.get_or_create(model=model, **kwargs)
except Graph.MultipleObjectsReturned:
raise ValueError("There is more than one graph for %s with %s" % (model, kwargs))
if not created:
# FIXME: workflow_graph_needs_upgrade is broken because it alters the Args instance.
if not force and not workflow_graph_needs_upgrade(graph, nodes, edges):
return False
graph.auto_start = False
graph.save()
graph = Graph.objects.create(model=model, **kwargs)
node_instances = {}
for name, args in nodes.items():
args.setdefault('name', " ".join(camel_split(args[0].__name__)))
args.setdefault('uid', name)
group = args.pop('group', None)
is_delegatable = args.pop('is_delegatable', None)
is_dynamic = args.pop('is_dynamic', None)
node = args.apply(graph.create_node)
node_instances[name] = node
if group:
task_type = TaskType.objects.get(workflow_node=node)
task_type.group = Group.objects.get(name=group)
task_type.save()
if not is_delegatable is None:
task_type = TaskType.objects.get(workflow_node=node)
task_type.is_delegatable = is_delegatable
task_type.save()
if not is_dynamic is None:
task_type = TaskType.objects.get(workflow_node=node)
task_type.is_dynamic = is_dynamic
task_type.save()
for node_names, args in edges:
if not args:
args = Args()
from_name, to_name = node_names
args.update(node_instances[to_name])
args.apply(node_instances[from_name].add_edge)
return True
def workflow_graph_needs_upgrade(graph, nodes, edges):
existing_nodes = {}
for name, args in nodes.iteritems():
args.pop('group', None)
try:
existing_nodes[name] = args.apply(graph.get_node)
except (Node.DoesNotExist, Node.MultipleObjectsReturned):
return True
for node_names, args in edges.iteritems():
if not args:
args = Args()
from_name, to_name = node_names
args.update(existing_nodes[to_name])
try:
args.apply(existing_nodes[from_name].get_edge)
except Edge.DoesNotExist:
return True
return False
def workflow_graph_needs_upgrade(graph, nodes, edges):
existing_nodes = {}
nodes = deepcopy(nodes)
for name, args in nodes.items():
args.setdefault('uid', name)
args.pop('group', None)
try:
existing_nodes[name] = args.apply(graph.get_node)
except (Node.DoesNotExist, Node.MultipleObjectsReturned):
return True
edges = deepcopy(edges)
for node_names, args in edges:
if not args:
args = Args()
from_name, to_name = node_names
args.update(existing_nodes[to_name])
try:
args.apply(existing_nodes[from_name].get_edge)
except Edge.DoesNotExist:
return True
return False
def setup_workflow_graph(model, nodes=None, edges=None, force=False, **kwargs):
"""
created a new workflow graph if a graph with the same structure does not already exists.
old graphs will loose their auto_start=True flag.
"""
try:
graph, created = Graph.objects.get_or_create(model=model, **kwargs)
except Graph.MultipleObjectsReturned:
raise ValueError("There is more than one graph for %s with %s" % (model, kwargs))
if not created:
if not force and not workflow_graph_needs_upgrade(graph, nodes, edges):
return False
graph.auto_start = False
graph.save()
graph = Graph.objects.create(model=model, **kwargs)
node_instances = {}
for name, args in nodes.iteritems():
args.setdefault('name', " ".join(camel_split(args[0].__name__)))
group = args.pop('group', None)
node = args.apply(graph.create_node)
node_instances[name] = node
if group:
task_type = TaskType.objects.get(workflow_node=node)
try:
task_type.groups.add(Group.objects.get(name=group))
except Group.DoesNotExist:
print "no such group: %s" % group
raise
for node_names, args in edges.iteritems():
if not args:
args = Args()
from_name, to_name = node_names
args.update(node_instances[to_name])
args.apply(node_instances[from_name].add_edge)
return True
