Add support for split and merge workflow patterns (#146)

* To split workflow a list of tasks is returned in jexl expression
* To merge multiple tasks of a workflow link to same flow

caluma/form/schema.py

@@ -261,6 +261,7 @@ class Meta:
         lookup_input_kwarg = "option"
         serializer_class = serializers.RemoveOptionSerializer
         return_field_name = False
+        model_operations = ["update"]
 
 
 class Answer(Node, graphene.Interface):

caluma/tests/snapshots/snap_test_schema.py

@@ -27,7 +27,7 @@
 
 input AddWorkflowFlowInput {
   workflow: ID!
-  task: ID!
+  tasks: [ID]!
   next: FlowJexl!
   clientMutationId: String
 }
@@ -250,9 +250,9 @@
 }
 
 type Flow implements Node {
-  task: Task!
   next: FlowJexl!
   id: ID!
+  tasks: [Task]!
 }
 
 type FlowConnection {
@@ -351,7 +351,7 @@
   publishWorkflow(input: PublishWorkflowInput!): PublishWorkflowPayload
   archiveWorkflow(input: ArchiveWorkflowInput!): ArchiveWorkflowPayload
   addWorkflowFlow(input: AddWorkflowFlowInput!): AddWorkflowFlowPayload
-  removeWorkflowFlow(input: RemoveWorkflowFlowInput!): RemoveWorkflowFlowPayload
+  removeFlow(input: RemoveFlowInput!): RemoveFlowPayload
   saveTask(input: SaveTaskInput!): SaveTaskPayload
   archiveTask(input: ArchiveTaskInput!): ArchiveTaskPayload
   startCase(input: StartCaseInput!): StartCasePayload
@@ -511,6 +511,16 @@
   id: ID!
 }
 
+input RemoveFlowInput {
+  flow: ID!
+  clientMutationId: String
+}
+
+type RemoveFlowPayload {
+  flow: Flow
+  clientMutationId: String
+}
+
 input RemoveFormQuestionInput {
   form: ID!
   question: ID!
@@ -531,17 +541,6 @@
   clientMutationId: String
 }
 
-input RemoveWorkflowFlowInput {
-  workflow: ID!
-  task: ID!
-  clientMutationId: String
-}
-
-type RemoveWorkflowFlowPayload {
-  workflow: Workflow
-  clientMutationId: String
-}
-
 input ReorderFormQuestionsInput {
   form: ID!
   questions: [ID]!
@@ -916,8 +915,8 @@
   isArchived: Boolean!
   start: Task!
   form: Form
-  flows(before: String, after: String, first: Int, last: Int, task: ID): FlowConnection
   id: ID!
+  flows(before: String, after: String, first: Int, last: Int, task: ID): FlowConnection
 }
 
 type WorkflowConnection {

caluma/tests/test_schema.py

@@ -8,7 +8,7 @@
 DIR_NAME = os.path.dirname(__file__)
 
 
-@pytest.mark.parametrize("node_type", ["form", "workflow", "flow", "task"])
+@pytest.mark.parametrize("node_type", ["form", "workflow", "task"])
 def test_schema_node(db, snapshot, request, node_type):
     """
     Add your model to parametrize for automatic global node testing.

caluma/workflow/factories.py

@@ -32,14 +32,21 @@ class Meta:
 
 
 class FlowFactory(DjangoModelFactory):
-    workflow = SubFactory(WorkflowFactory)
-    task = SubFactory(TaskFactory)
     next = Faker("slug")
 
     class Meta:
         model = models.Flow
 
 
+class TaskFlowFactory(DjangoModelFactory):
+    workflow = SubFactory(WorkflowFactory)
+    task = SubFactory(TaskFactory)
+    flow = SubFactory(FlowFactory)
+
+    class Meta:
+        model = models.TaskFlow
+
+
 class CaseFactory(DjangoModelFactory):
     workflow = SubFactory(WorkflowFactory)
     status = models.Case.STATUS_RUNNING

caluma/workflow/filters.py

@@ -1,5 +1,5 @@
 from . import models
-from ..core.filters import FilterSet, OrderingFilter, SearchFilter
+from ..core.filters import FilterSet, GlobalIDFilter, OrderingFilter, SearchFilter
 
 
 class WorkflowFilterSet(FilterSet):
@@ -11,6 +11,14 @@ class Meta:
         fields = ("slug", "name", "description", "is_published", "is_archived")
 
 
+class FlowFilterSet(FilterSet):
+    task = GlobalIDFilter(field_name="task_flows__task")
+
+    class Meta:
+        model = models.Flow
+        fields = ("task",)
+
+
 class CaseFilterSet(FilterSet):
     order_by = OrderingFilter(label="CaseOrdering", fields=("status",))
 

caluma/workflow/jexl.py

@@ -1,4 +1,5 @@
 from functools import partial
+from itertools import chain
 
 from pyjexl import JEXL
 
@@ -9,8 +10,19 @@ class FlowJexl(JEXL):
     def __init__(self, **kwargs):
         super().__init__(**kwargs)
         self.add_transform("task", lambda spec: spec)
+        self.add_transform("tasks", lambda spec: spec)
 
     def extract_tasks(self, expr):
-        return self.analyze(
+        yield from self.analyze(
             expr, partial(ExtractTransformSubjectAnalyzer, transforms=["task"])
         )
+
+        # tasks transforms return a list of literals
+        yield from (
+            literal.value
+            for literal in chain(
+                *self.analyze(
+                    expr, partial(ExtractTransformSubjectAnalyzer, transforms=["tasks"])
+                )
+            )
+        )

caluma/workflow/migrations/0006_auto_20181207_1512.py

@@ -0,0 +1,72 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.17 on 2018-12-07 15:12
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+import uuid
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [("workflow", "0005_workitem_child_case")]
+
+    operations = [
+        migrations.CreateModel(
+            name="TaskFlow",
+            fields=[
+                ("created_at", models.DateTimeField(auto_now_add=True)),
+                ("modified_at", models.DateTimeField(auto_now=True)),
+                (
+                    "created_by_user",
+                    models.CharField(blank=True, max_length=150, null=True),
+                ),
+                (
+                    "created_by_group",
+                    models.CharField(blank=True, max_length=150, null=True),
+                ),
+                (
+                    "id",
+                    models.UUIDField(
+                        default=uuid.uuid4,
+                        editable=False,
+                        primary_key=True,
+                        serialize=False,
+                    ),
+                ),
+            ],
+        ),
+        migrations.AlterUniqueTogether(name="flow", unique_together=set([])),
+        migrations.AddField(
+            model_name="taskflow",
+            name="flow",
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="task_flows",
+                to="workflow.Flow",
+            ),
+        ),
+        migrations.AddField(
+            model_name="taskflow",
+            name="task",
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="task_flows",
+                to="workflow.Task",
+            ),
+        ),
+        migrations.AddField(
+            model_name="taskflow",
+            name="workflow",
+            field=models.ForeignKey(
+                on_delete=django.db.models.deletion.CASCADE,
+                related_name="task_flows",
+                to="workflow.Workflow",
+            ),
+        ),
+        migrations.RemoveField(model_name="flow", name="task"),
+        migrations.RemoveField(model_name="flow", name="workflow"),
+        migrations.AlterUniqueTogether(
+            name="taskflow", unique_together=set([("workflow", "task")])
+        ),
+    ]

caluma/workflow/models.py

@@ -35,10 +35,16 @@ class Workflow(SlugModel):
 
 
 class Flow(UUIDModel):
-    workflow = models.ForeignKey(Workflow, related_name="flows")
-    task = models.ForeignKey(Task, related_name="flows")
     next = models.TextField()
 
+
+class TaskFlow(UUIDModel):
+    workflow = models.ForeignKey(
+        Workflow, on_delete=models.CASCADE, related_name="task_flows"
+    )
+    task = models.ForeignKey(Task, related_name="task_flows", on_delete=models.CASCADE)
+    flow = models.ForeignKey(Flow, related_name="task_flows", on_delete=models.CASCADE)
+
     class Meta:
         unique_together = ("workflow", "task")
 

caluma/workflow/schema.py

@@ -19,30 +19,36 @@ class FlowJexl(graphene.String):
 )
 
 
+class Task(DjangoObjectType):
+    class Meta:
+        model = models.Task
+        exclude_fields = ("task_flows", "work_items")
+        interfaces = (relay.Node,)
+
+
 class Flow(DjangoObjectType):
     next = FlowJexl(required=True)
+    tasks = graphene.List(Task, required=True)
+
+    def resolve_tasks(self, info, **args):
+        return models.Task.objects.filter(pk__in=self.task_flows.values("task"))
 
     class Meta:
         model = models.Flow
-        filter_fields = ("task",)
-        only_fields = ("task", "next")
+        only_fields = ("tasks", "next")
         interfaces = (relay.Node,)
 
 
 class Workflow(DjangoObjectType):
-    flows = DjangoFilterConnectionField(Flow)
+    flows = DjangoFilterConnectionField(Flow, filterset_class=filters.FlowFilterSet)
+
+    def resolve_flows(self, info, **args):
+        return models.Flow.objects.filter(pk__in=self.task_flows.values("flow"))
 
     class Meta:
         model = models.Workflow
         filter_fields = ("slug", "name", "description", "is_published", "is_archived")
-        exclude_fields = ("cases",)
-        interfaces = (relay.Node,)
-
-
-class Task(DjangoObjectType):
-    class Meta:
-        model = models.Task
-        exclude_fields = ("flows", "work_items")
+        exclude_fields = ("cases", "task_flows")
         interfaces = (relay.Node,)
 
 
@@ -81,10 +87,11 @@ class Meta:
         lookup_input_kwarg = "workflow"
 
 
-class RemoveWorkflowFlow(Mutation):
+class RemoveFlow(Mutation):
     class Meta:
-        serializer_class = serializers.RemoveWorkflowFlowSerializer
-        lookup_input_kwarg = "workflow"
+        lookup_input_kwarg = "flow"
+        serializer_class = serializers.RemoveFlowSerializer
+        model_operations = ["update"]
 
 
 class SaveTask(UserDefinedPrimaryKeyMixin, Mutation):
@@ -121,7 +128,7 @@ class Mutation(object):
     publish_workflow = PublishWorkflow().Field()
     archive_workflow = ArchiveWorkflow().Field()
     add_workflow_flow = AddWorkflowFlow().Field()
-    remove_workflow_flow = RemoveWorkflowFlow().Field()
+    remove_flow = RemoveFlow().Field()
 
     save_task = SaveTask().Field()
     archive_task = ArchiveTask().Field()