Add unit tests for loading photoscans from database (#198)

Author: sadhana-r

src/openlifu/db/database.py

@@ -631,7 +631,11 @@ def get_photoscan_absolute_filepaths_info(self, subject_id, session_id, photosca
     def load_photoscan(self, subject_id, session_id, photoscan_id, load_data = False):
         """Returns a photoscan object and optionally, also returns the loaded model and texture
         data as Tuple[vtkPolyData, vtkImageData] if load_data = True."""
+
         photoscan_metadata_filepath = self.get_photoscan_metadata_filepath(subject_id, session_id, photoscan_id)
+        if not photoscan_metadata_filepath.exists() or not photoscan_metadata_filepath.is_file():
+            raise FileNotFoundError(f"Photoscan file not found for photoscan {photoscan_id}, session {session_id}")
+
         photoscan = Photoscan.from_file(photoscan_metadata_filepath)
 
         if load_data:

tests/test_database.py

@@ -8,6 +8,7 @@
 
 import pytest
 from helpers import dataclasses_are_equal
+from vtk import vtkImageData, vtkPolyData
 
 from openlifu import Point, Solution
 from openlifu.db import Session, Subject
@@ -497,6 +498,19 @@ def test_write_photoscan(example_database:Database, example_session: Session, tm
     with pytest.raises(FileNotFoundError, match="does not exist"):
         example_database.write_photoscan(example_session.subject_id, example_session.id, photoscan, model_data_path, bogus_texture_file, on_conflict=OnConflictOpts.OVERWRITE)
 
+def test_load_photoscan(example_database:Database, example_session:Session):
+    with pytest.raises(FileNotFoundError,match="Photoscan file not found"):
+        example_database.load_photoscan(example_session.subject_id, example_session.id, "bogus_photoscan_id")
+
+    example_photoscan = example_database.load_photoscan(example_session.subject_id, example_session.id, "example_photoscan")
+    assert example_photoscan.name == "ExamplePhotoscan"
+
+    example_photoscan, (model_data, texture_data) = example_database.load_photoscan(example_session.subject_id, example_session.id, "example_photoscan", load_data=True)
+    assert model_data is not None
+    assert texture_data is not None
+    assert isinstance(model_data, vtkPolyData)
+    assert isinstance(texture_data,vtkImageData)
+
 def test_session_created_date():
     """Test that created date is recent when a session is created."""
     tolerance = timedelta(seconds=2)  # Allow for minor timing discrepancies

tests/test_photoscans.py

@@ -35,7 +35,7 @@ def test_load_photoscan(example_database:Database, tmp_path:Path):
     subject_id = "example_subject"
     session_id = "example_session"
     photoscan_id = "example_photoscan"
-    photoscan_info = example_database.get_photoscan_info(subject_id, session_id, photoscan_id)
+    photoscan_info = example_database.get_photoscan_absolute_filepaths_info(subject_id, session_id, photoscan_id)
     [model, texture] = load_data_from_filepaths(photoscan_info["model_abspath"], photoscan_info["texture_abspath"])
     assert model is not None
     assert texture is not None