IQR: guard against None and return empty images

Author: floryst

rdwatch/core/models/site_evaluation.py

@@ -158,6 +158,9 @@ def bulk_create_from_site_model(
 
             point = None
             geom = None
+            smqtk_uuid = None
+            if site_feature.properties.cache:
+                smqtk_uuid = site_feature.properties.cache.smqtk_uuid
             if isinstance(site_feature.parsed_geometry, Point):
                 point = site_feature.parsed_geometry
             else:
@@ -177,7 +180,7 @@ def bulk_create_from_site_model(
                 cache_originator_file=cache_originator_file,
                 cache_timestamp=cache_timestamp,
                 cache_commit_hash=cache_commit_hash,
-                smqtk_uuid=site_feature.properties.cache.smqtk_uuid,
+                smqtk_uuid=smqtk_uuid,
                 modified_timestamp=datetime.now(),
             )
             SiteObservation.bulk_create_from_site_evaluation(site_eval, site_model)

rdwatch/core/views/iqr.py

@@ -129,12 +129,12 @@ def get_session_info(request: HttpRequest, sid: str):
     return 200, resp.json()
 
 
-def pick_site_image(images: list[SiteImage], observations: list[SiteObservation]):
+def pick_site_image(images: list[SiteImage], observations: list[SiteObservation]) -> SiteImage | None:
     # ignore observations with no timestamps
     observations = [o for o in observations if o.timestamp is not None]
 
     if not len(images):
-        raise Exception('no observations or images')
+        return None
     if not len(observations):
         return images[-1]