Implement UFCN custom_open_image behaviour in basic open_image function

arkindex_worker/models.py

@@ -55,6 +55,14 @@ class Element(MagicDict):
     Describes any kind of element.
     """
 
+    def resize_zone_url(self, size="full"):
+        if size == "full":
+            return self.zone.url
+        else:
+            parts = self.zone.url.split("/")
+            parts[-3] = size
+            return "/".join(parts)
+
     def image_url(self, size="full"):
         """
         When possible, will return the S3 URL for images, so an ML worker can bypass IIIF servers
@@ -79,10 +87,16 @@ class Element(MagicDict):
         bounding_box = polygon_bounding_box(self.zone.polygon)
         return bounding_box.width > max_width or bounding_box.height > max_height
 
-    def open_image(self, *args, max_size=None, **kwargs):
+    def open_image(self, *args, max_size=None, use_full_image=False, **kwargs):
         """
         Open this element's image as a Pillow image.
-        This does not crop the image to the element's polygon.
+
+        If use_full_image is False:
+            Use zone url, instead of the full image url to be able to get
+            single page from double page image.
+        Else:
+            This does not crop the image to the element's polygon.
+
         :param max_size: Subresolution of the image.
         """
         if not self.get("zone"):
@@ -119,7 +133,10 @@ class Element(MagicDict):
             resize = "full"
 
         try:
-            return open_image(self.image_url(resize), *args, **kwargs)
+            if use_full_image:
+                return open_image(self.image_url(resize), *args, **kwargs)
+            else:
+                return open_image(self.resize_zone_url(resize), *args, **kwargs)
         except HTTPError as e:
             if (
                 self.zone.image.get("s3_url") is not None

tests/test_element.py

@@ -62,7 +62,7 @@ def test_open_image(mocker):
             }
         }
     )
-    assert elt.open_image() == "an image!"
+    assert elt.open_image(use_full_image=True) == "an image!"
     assert open_mock.call_count == 1
     assert open_mock.call_args == mocker.call(
         "http://something/full/full/0/default.jpg"
@@ -87,19 +87,19 @@ def test_open_image_resize_portrait(mocker):
         }
     )
     # Resize = original size
-    assert elt.open_image(max_size=600) == "an image!"
+    assert elt.open_image(max_size=600, use_full_image=True) == "an image!"
     assert open_mock.call_count == 1
     assert open_mock.call_args == mocker.call(
         "http://something/full/full/0/default.jpg"
     )
     # Resize = smaller height
-    assert elt.open_image(max_size=400) == "an image!"
+    assert elt.open_image(max_size=400, use_full_image=True) == "an image!"
     assert open_mock.call_count == 2
     assert open_mock.call_args == mocker.call(
         "http://something/full/266,400/0/default.jpg"
     )
     # Resize = bigger height
-    assert elt.open_image(max_size=800) == "an image!"
+    assert elt.open_image(max_size=800, use_full_image=True) == "an image!"
     assert open_mock.call_count == 3
     assert open_mock.call_args == mocker.call(
         "http://something/full/full/0/default.jpg"
@@ -123,7 +123,7 @@ def test_open_image_resize_partial_element(mocker):
             }
         }
     )
-    assert elt.open_image(max_size=400) == "an image!"
+    assert elt.open_image(max_size=400, use_full_image=True) == "an image!"
     assert open_mock.call_count == 1
     assert open_mock.call_args == mocker.call(
         "http://something/full/full/0/default.jpg"
@@ -148,19 +148,19 @@ def test_open_image_resize_landscape(mocker):
         }
     )
     # Resize = original size
-    assert elt.open_image(max_size=600) == "an image!"
+    assert elt.open_image(max_size=600, use_full_image=True) == "an image!"
     assert open_mock.call_count == 1
     assert open_mock.call_args == mocker.call(
         "http://something/full/full/0/default.jpg"
     )
     # Resize = smaller width
-    assert elt.open_image(max_size=400) == "an image!"
+    assert elt.open_image(max_size=400, use_full_image=True) == "an image!"
     assert open_mock.call_count == 2
     assert open_mock.call_args == mocker.call(
         "http://something/full/400,266/0/default.jpg"
     )
     # Resize = bigger width
-    assert elt.open_image(max_size=800) == "an image!"
+    assert elt.open_image(max_size=800, use_full_image=True) == "an image!"
     assert open_mock.call_count == 3
     assert open_mock.call_args == mocker.call(
         "http://something/full/full/0/default.jpg"
@@ -185,19 +185,19 @@ def test_open_image_resize_square(mocker):
         }
     )
     # Resize = original size
-    assert elt.open_image(max_size=400) == "an image!"
+    assert elt.open_image(max_size=400, use_full_image=True) == "an image!"
     assert open_mock.call_count == 1
     assert open_mock.call_args == mocker.call(
         "http://something/full/full/0/default.jpg"
     )
     # Resize = smaller
-    assert elt.open_image(max_size=200) == "an image!"
+    assert elt.open_image(max_size=200, use_full_image=True) == "an image!"
     assert open_mock.call_count == 2
     assert open_mock.call_args == mocker.call(
         "http://something/full/200,200/0/default.jpg"
     )
     # Resize = bigger
-    assert elt.open_image(max_size=800) == "an image!"
+    assert elt.open_image(max_size=800, use_full_image=True) == "an image!"
     assert open_mock.call_count == 3
     assert open_mock.call_args == mocker.call(
         "http://something/full/full/0/default.jpg"
@@ -234,7 +234,7 @@ def test_open_image_s3(mocker):
     elt = Element(
         {"zone": {"image": {"url": "http://something", "s3_url": "http://s3url"}}}
     )
-    assert elt.open_image() == "an image!"
+    assert elt.open_image(use_full_image=True) == "an image!"
     assert open_mock.call_count == 1
     assert open_mock.call_args == mocker.call("http://s3url")
 
@@ -256,7 +256,7 @@ def test_open_image_s3_retry(mocker):
     )
 
     with pytest.raises(NotImplementedError):
-        elt.open_image()
+        elt.open_image(use_full_image=True)
 
 
 def test_open_image_s3_retry_once(mocker):
@@ -274,4 +274,4 @@ def test_open_image_s3_retry_once(mocker):
     )
 
     with pytest.raises(NotImplementedError):
-        elt.open_image()
+        elt.open_image(use_full_image=True)