Use functools.cache instead of PromiseProxy to load schema from

igwn-gwalert-schema

gwcelery/kafka/bootsteps.py

+from functools import cache
+
 from celery import bootsteps
 from celery.concurrency import solo
 from celery.utils.log import get_logger
@@ -7,7 +9,7 @@ from hop import stream
 from hop.io import list_topics
 from hop.models import AvroBlob, JSONBlob
 
-from ..util import PromiseProxy, read_json
+from ..util import read_json
 
 
 __all__ = ('Producer',)
@@ -15,7 +17,7 @@ __all__ = ('Producer',)
 log = get_logger(__name__)
 
 
-@PromiseProxy
+@cache
 def schema():
     # The order does not matter other than the Alert schema must be loaded last
     # because it references the other schema. All of the schema are saved in
@@ -42,12 +44,7 @@ def schema():
 class AvroBlobWrapper(AvroBlob):
 
     def __init__(self, payload):
-        # NOTE fastavro appears to not like something about this PromiseProxy
-        # object. Returning a copy of the object is the only workaround I could
-        # find.
-        # FIXME Understand this behavior and write a less hacky fix. Possibly
-        # switch to using functools.cache once python3.8 support is dropped
-        return super().__init__([payload], schema.copy())
+        return super().__init__([payload], schema())
 
 
 class KafkaWriter:

gwcelery/tests/test_tasks_alerts_validate.py

@@ -11,29 +11,19 @@ from . import data
 from ..kafka.bootsteps import AvroBlobWrapper, schema
 
 
-@pytest.fixture
-def copied_schema():
-    # NOTE The unit test appears to not like something about this PromiseProxy
-    # object. Returning a copy of the object is the only workaround I could
-    # find.
-    # FIXME Understand this behavior and write a less hacky fix
-    return schema.copy()
-
-
 @patch('gwcelery.tasks.alerts._upload_notice.run')
 @patch('gwcelery.tasks.gracedb.download._orig_run',
        return_value=resources.read_binary(
            data,
            'MS220722v_bayestar.multiorder.fits'
        ))
-def test_validate_alert(mock_download, mock_upload, copied_schema,
-                        monkeypatch):
+def test_validate_alert(mock_download, mock_upload, monkeypatch):
     """Validate public alerts against the schema from the userguide.
     """
     def _validate_alert(public_alert_avro_blob):
         assert len(public_alert_avro_blob.content) == 1
         fastavro.validation.validate(public_alert_avro_blob.content[0],
-                                     copied_schema, strict=True)
+                                     schema(), strict=True)
 
     # Replace the stream object with a mock object with _validiate_alert as its
     # write attribute