From c87908dfae4041ad40f7262d56379866669bb154 Mon Sep 17 00:00:00 2001
From: Oliver Sauder <oliver.sauder@adfinis-sygroup.ch>
Date: Thu, 13 Dec 2018 14:31:49 +0100
Subject: [PATCH] Let a document only be assigned to one case

A case enforces a workflow so it doesn't make sense to edit
the same document in two different workflows.
---
 caluma/form/schema.py                         |  1 -
 caluma/tests/snapshots/snap_test_schema.py    |  1 +
 .../migrations/0002_auto_20181213_1334.py     | 25 +++++++++++++++++++
 caluma/workflow/models.py                     |  6 ++---
 4 files changed, 29 insertions(+), 4 deletions(-)
 create mode 100644 caluma/workflow/migrations/0002_auto_20181213_1334.py

diff --git a/caluma/form/schema.py b/caluma/form/schema.py
index 02393f25e..7c1055bfb 100644
--- a/caluma/form/schema.py
+++ b/caluma/form/schema.py
@@ -346,7 +346,6 @@ class Document(DjangoObjectType):
     class Meta:
         model = models.Document
         interfaces = (graphene.Node,)
-        exclude_fields = ("cases",)
         filter_fields = ("form",)
 
 
diff --git a/caluma/tests/snapshots/snap_test_schema.py b/caluma/tests/snapshots/snap_test_schema.py
index 3991afe9e..e736cdb2f 100644
--- a/caluma/tests/snapshots/snap_test_schema.py
+++ b/caluma/tests/snapshots/snap_test_schema.py
@@ -198,6 +198,7 @@
   form: Form!
   meta: JSONString!
   answers(before: String, after: String, first: Int, last: Int, question: ID, search: String, orderBy: [AnswerOrdering]): AnswerConnection
+  case: Case
 }
 
 type DocumentConnection {
diff --git a/caluma/workflow/migrations/0002_auto_20181213_1334.py b/caluma/workflow/migrations/0002_auto_20181213_1334.py
new file mode 100644
index 000000000..22f47c76d
--- /dev/null
+++ b/caluma/workflow/migrations/0002_auto_20181213_1334.py
@@ -0,0 +1,25 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.17 on 2018-12-13 13:34
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [("workflow", "0001_initial")]
+
+    operations = [
+        migrations.AlterField(
+            model_name="case",
+            name="document",
+            field=models.OneToOneField(
+                blank=True,
+                null=True,
+                on_delete=django.db.models.deletion.PROTECT,
+                related_name="case",
+                to="form.Document",
+            ),
+        )
+    ]
diff --git a/caluma/workflow/models.py b/caluma/workflow/models.py
index 28d4c228c..a5295b2c6 100644
--- a/caluma/workflow/models.py
+++ b/caluma/workflow/models.py
@@ -66,10 +66,10 @@ class Case(UUIDModel):
     )
     status = models.CharField(choices=STATUS_CHOICE_TUPLE, max_length=50, db_index=True)
     meta = JSONField(default={})
-    document = models.ForeignKey(
+    document = models.OneToOneField(
         "form.Document",
-        on_delete=models.DO_NOTHING,
-        related_name="cases",
+        on_delete=models.PROTECT,
+        related_name="case",
         blank=True,
         null=True,
     )