Put a template's indexed image first in Examples

src/test/test_examples_order.py

@@ -0,0 +1,41 @@
+"""Available Images order: a template's own domain image leads."""
+import unittest
+
+from vfbquery.vfb_queries import order_template_examples
+
+
+class OrderTemplateExamplesTest(unittest.TestCase):
+
+    def test_indexed_image_first_then_newest_id(self):
+        # FBbt_00003748 on JRC2018U: the painted domain VFB_00102107 has the
+        # oldest id but is the only image indexed to the template.
+        records = [
+            {"id": "VFB_00107fo8"},
+            {"id": "VFB_00102107", "index": 3},
+            {"id": "VFB_001091st"},
+            {"id": "VFB_00108iwp"},
+        ]
+        self.assertEqual(
+            [r["id"] for r in order_template_examples(records)],
+            ["VFB_00102107", "VFB_001091st", "VFB_00108iwp", "VFB_00107fo8"])
+
+    def test_several_indexed_images_ascend_by_index(self):
+        records = [
+            {"id": "VFB_0000000a", "index": 7},
+            {"id": "VFB_0000000b"},
+            {"id": "VFB_0000000c", "index": 0},
+            {"id": "VFB_0000000d", "index": 2},
+        ]
+        self.assertEqual(
+            [r["id"] for r in order_template_examples(records)],
+            ["VFB_0000000c", "VFB_0000000d", "VFB_0000000a", "VFB_0000000b"])
+
+    def test_no_index_keeps_id_descending(self):
+        records = [{"id": "VFB_00000001"}, {"id": "VFB_00000003"}, {"id": "VFB_00000002"}]
+        self.assertEqual(
+            [r["id"] for r in order_template_examples(records)],
+            ["VFB_00000003", "VFB_00000002", "VFB_00000001"])
+
+
+if __name__ == "__main__":
+    unittest.main()

src/vfbquery/vfb_queries.py

@@ -360,6 +360,17 @@ def __init__(self, id, label, thumbnail=None, thumbnail_transparent=None, nrrd=N
         self.type_label = type_label
         self.type_id = type_id
 
+def order_template_examples(records):
+    """Order one template's Examples so its own domain images come first.
+
+    An image with an index is a domain in that template's label volume, so it
+    belongs to the template and leads the Available Images carousel, by index
+    ascending. Everything else follows, newest id first as before.
+    """
+    by_id = sorted(records, key=lambda r: r["id"], reverse=True)
+    return sorted(by_id, key=lambda r: (r.get("index") is None, r.get("index") or 0))
+
+
 class ImageSchema(Schema):
     id = fields.String(required=True)
     label = fields.String(required=True)
@@ -963,11 +974,13 @@ def term_info_parse_object(results, short_form):
                 for key in vars(image.channel_image.image).keys():
                     if "image_" in key and not ("thumbnail" in key or "folder" in key) and len(vars(image.channel_image.image)[key]) > 1:
                         record[key.replace("image_","")] = vars(image.channel_image.image)[key].replace("http://","https://")
+                image_index = getattr(image.channel_image.image, "index", None)
+                if image_index:
+                    record["index"] = int(image_index[0])
                 images[image.channel_image.image.template_anatomy.short_form].append(record)
 
-            # Sort each template's images by id in descending order (newest first)
             for template_key in images:
-                images[template_key] = sorted(images[template_key], key=lambda x: x["id"], reverse=True)
+                images[template_key] = order_template_examples(images[template_key])
 
             termInfo["Examples"] = images
             # Add techniques to termInfo for Individuals