feat: sort stac_extensions

Author: gadomski

stactask/task.py

@@ -262,15 +262,21 @@ def post_process_item(self, item: Dict[str, Any]) -> Dict[str, Any]:
         E.g. add software version information.
 
         Most tasks should prefer to not override this method, as logic should be
-        kept in :py:meth:`Task.process`.
+        kept in :py:meth:`Task.process`. If you do override this method, make
+        sure to call ``super().post_process_item()`` AFTER doing any custom
+        post-processing, so any regular behavior can take your changes into account.
 
         Args:
             item: An item produced by :py:meth:`Task.process`
 
         Returns:
             Dict[str, Any]: The item with any additional attributes applied.
         """
-        return self.add_software_version_to_item(item)
+        item = self.add_software_version_to_item(item)
+        assert "stac_extensions" in item
+        assert isinstance(item["stac_extensions"], list)
+        item["stac_extensions"].sort()
+        return item
 
     @classmethod
     def handler(cls, payload: Dict[str, Any], **kwargs: Any) -> Dict[str, Any]:

tests/test_task.py

@@ -99,14 +99,16 @@ class PostProcessTask(NothingTask):
         version = "42"
 
         def post_process_item(self, item: Dict[str, Any]) -> Dict[str, Any]:
-            item = super().post_process_item(item)
             item["properties"]["foo"] = "bar"
-            return item
+            item["stac_extensions"].insert(0, "zzz")
+            return super().post_process_item(item)
 
     payload = PostProcessTask.handler(items)
     for item in payload["features"]:
         assert item["properties"]["foo"] == "bar"
         assert item["properties"]["processing:software"]["post-processing-test"] == "42"
+        stac_extensions = item["stac_extensions"]
+        assert item["stac_extensions"] == sorted(stac_extensions)
 
 
 def test_derived_item(derived_item_task: Task) -> None: