From 5cddb33c2319f312e4a82363ae6e43a53119666a Mon Sep 17 00:00:00 2001
From: Stefaan Lippens <stefaan.lippens@vito.be>
Date: Tue, 26 Mar 2024 07:47:34 +0100
Subject: [PATCH] Issue #527/#548 minor `metadata_from_stac` fine-tuning

---
 openeo/metadata.py     | 13 ++++++-------
 tests/test_metadata.py |  2 ++
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/openeo/metadata.py b/openeo/metadata.py
index af15a913d..9e1e55650 100644
--- a/openeo/metadata.py
+++ b/openeo/metadata.py
@@ -534,6 +534,7 @@ def metadata_from_stac(url: str) -> CubeMetadata:
     """
 
     def get_band_metadata(eo_bands_location: dict) -> List[Band]:
+        # TODO: return None iso empty list when no metadata?
         return [
             Band(name=band["name"], common_name=band.get("common_name"), wavelength_um=band.get("center_wavelength"))
             for band in eo_bands_location.get("eo:bands", [])
@@ -547,15 +548,12 @@ def is_band_asset(asset: pystac.Asset) -> bool:
 
     stac_object = pystac.read_file(href=url)
 
-    bands = []
-    collection = None
-
     if isinstance(stac_object, pystac.Item):
         item = stac_object
         if "eo:bands" in item.properties:
             eo_bands_location = item.properties
         elif item.get_collection() is not None:
-            collection = item.get_collection()
+            # TODO: Also do asset based band detection (like below)?
             eo_bands_location = item.get_collection().summaries.lists
         else:
             eo_bands_location = {}
@@ -574,12 +572,13 @@ def is_band_asset(asset: pystac.Asset) -> bool:
                 for asset_band in asset_bands:
                     if asset_band.name not in get_band_names(bands):
                         bands.append(asset_band)
-
-    else:
-        assert isinstance(stac_object, pystac.Catalog)
+    elif isinstance(stac_object, pystac.Catalog):
         catalog = stac_object
         bands = get_band_metadata(catalog.extra_fields.get("summaries", {}))
+    else:
+        raise ValueError(stac_object)
 
+    # TODO: conditionally include band dimension when there was actual indication of band metadata?
     band_dimension = BandDimension(name="bands", bands=bands)
     metadata = CubeMetadata(dimensions=[band_dimension])
     return metadata
diff --git a/tests/test_metadata.py b/tests/test_metadata.py
index 9a23fd9f0..e90d21558 100644
--- a/tests/test_metadata.py
+++ b/tests/test_metadata.py
@@ -806,6 +806,7 @@ def filter_bbox(self, bbox):
             },
             ["B01", "B02"],
         ),
+        # TODO: test asset handling in collection?
         (
             {
                 "type": "Catalog",
@@ -830,6 +831,7 @@ def filter_bbox(self, bbox):
             },
             ["SCL", "B08"],
         ),
+        # TODO: test asset handling in item?
     ],
 )
 def test_metadata_from_stac(tmp_path, test_stac, expected):