Add image field on element update APIs

arkindex/documents/serializers/elements.py

@@ -212,11 +212,24 @@ class ElementSerializer(ElementSlimSerializer):
 
     metadata = serializers.SerializerMethodField()
     classifications = ClassificationSerializer(many=True, read_only=True)
-    polygon = PolygonField(required=False)
+    image = serializers.PrimaryKeyRelatedField(
+        queryset=Image.objects.all(),
+        required=False,
+        write_only=True,
+        help_text='Link this element to an image by UUID via a polygon. '
+                  'When the image is updated, if there was an image before and the polygon is not updated, '
+                  'the previous polygon is reused. Otherwise, a polygon filling the new image is used.'
+    )
+    polygon = PolygonField(
+        required=False,
+        write_only=True,
+        help_text='Set the polygon linking this element to the image. '
+                  '`image` must be set when this field is set and there was no image or polygon defined before.',
+    )
 
     class Meta:
         model = Element
-        fields = ElementSlimSerializer.Meta.fields + ('metadata', 'classifications', 'polygon')
+        fields = ElementSlimSerializer.Meta.fields + ('metadata', 'classifications', 'image', 'polygon')
         read_only_fields = ElementSlimSerializer.Meta.read_only_fields + ('metadata', 'classifications')
 
     def create(self, *args, **kwargs):
@@ -225,16 +238,25 @@ class ElementSerializer(ElementSlimSerializer):
         return instance
 
     def update(self, instance, validated_data):
+        image = validated_data.pop('image', None)
         polygon = validated_data.pop('polygon', None)
-        if polygon:
-            if not instance.zone:
-                raise ValidationError({
-                    'polygon': ['Zone not found']
-                })
-            zone, _ = instance.zone.image.zones.get_or_create(
-                polygon=polygon,
-            )
-            instance.zone = zone
+        if polygon or image:
+            if not image:
+                if not instance.zone:
+                    # A polygon was set but there is no image
+                    raise ValidationError({
+                        'image': ['Image is required when defining a polygon on an element without an existing zone'],
+                    })
+                image = instance.zone.image
+
+            if not polygon:
+                if instance.zone:
+                    polygon = instance.zone.polygon
+                else:
+                    polygon = Polygon.from_coords(0, 0, image.width, image.height)
+
+            instance.zone, _ = image.zones.get_or_create(polygon=polygon)
+
         instance = super().update(instance, validated_data)
         instance.events.create(type=EventType.Edit)
         return instance

arkindex/documents/tests/test_elements_api.py

@@ -190,6 +190,7 @@ class TestElementsAPI(FixtureAPITestCase):
 
     def test_patch_element_polygon(self):
         self.client.force_login(self.user)
+        self.assertIsNotNone(self.element.zone)
         response = self.client.patch(
             reverse('api:element-retrieve', kwargs={'pk': str(self.element.id)}),
             data={
@@ -206,9 +207,10 @@ class TestElementsAPI(FixtureAPITestCase):
         self.assertEqual(self.element.zone.polygon.width, 20)
         self.assertEqual(self.element.zone.polygon.height, 10)
 
-    def test_patch_element_polygon_wrong_zone(self):
+    def test_patch_element_polygon_without_image(self):
         self.client.force_login(self.user)
-        self.assertIsNone(self.vol.zone)
+        self.vol.zone = None
+        self.vol.save()
         response = self.client.patch(
             reverse('api:element-retrieve', kwargs={'pk': str(self.vol.id)}),
             data={
@@ -217,7 +219,44 @@ class TestElementsAPI(FixtureAPITestCase):
             format='json',
         )
         self.assertEqual(response.status_code, status.HTTP_400_BAD_REQUEST)
-        self.assertEqual(response.json()['polygon'], ['Zone not found'])
+        self.assertDictEqual(response.json(), {
+            'image': ['Image is required when defining a polygon on an element without an existing zone']
+        })
+
+    def test_patch_element_image_preserve_polygon(self):
+        self.client.force_login(self.user)
+        self.assertNotEqual(self.element.zone.image, self.image)
+        expected_polygon = self.element.zone.polygon.copy()
+        response = self.client.patch(
+            reverse('api:element-retrieve', kwargs={'pk': str(self.element.id)}),
+            data={
+                'image': str(self.image.id),
+            },
+            format='json',
+        )
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.element.refresh_from_db()
+        self.assertEqual(self.element.zone.image, self.image)
+        self.assertEqual(self.element.zone.polygon, expected_polygon)
+
+    def test_patch_element_new_zone(self):
+        self.client.force_login(self.user)
+        self.assertIsNone(self.vol.zone)
+        response = self.client.patch(
+            reverse('api:element-retrieve', kwargs={'pk': str(self.vol.id)}),
+            data={
+                'image': str(self.image.id),
+                'polygon': [[10, 20], [10, 30], [30, 30], [30, 20], [10, 20]],
+            },
+            format='json',
+        )
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.vol.refresh_from_db()
+        self.assertEqual(self.vol.zone.image, self.image)
+        self.assertEqual(self.vol.zone.polygon.x, 10)
+        self.assertEqual(self.vol.zone.polygon.y, 20)
+        self.assertEqual(self.vol.zone.polygon.width, 20)
+        self.assertEqual(self.vol.zone.polygon.height, 10)
 
     def make_create_request(self, name='default', corpus=None, elt_type='volume', **options):
         request = {