Merge remote-tracking branch 'origin/main'

# Conflicts:
#	CHANGES.md

Author: forman

CHANGES.md

@@ -12,6 +12,11 @@
 
 ### Other changes
 
+* Added a new abstract class `PreloadedDataStore` that defines the return type of the
+  `preload_data` method in `xcube.core.store.DataStore`. The `PreloadedDataStore` is a
+  data store containing a `preload_handle` field, which holds the handle
+  associated with a preload job.
+
 * Renamed [xrlint]() config file from `xrlint_config.yaml` to `xrlint-config.yaml`.
 
 ## Changes in 1.8.3

test/core/store/test_store.py

@@ -7,7 +7,13 @@
 import pytest
 from fsspec.registry import register_implementation
 
-from xcube.core.store import DataStoreError, list_data_store_ids, new_data_store
+from xcube.core.store import (
+    DataStoreError,
+    PreloadedDataStore,
+    list_data_store_ids,
+    new_data_store,
+)
+from xcube.core.store.preload import NullPreloadHandle
 
 
 class ListDataStoreTest(unittest.TestCase):
@@ -84,6 +90,12 @@ def test_has_data(self, mock_filesystem):
         self.assertEqual(mock_http_fs.exists.call_count, 3)
         self.assertFalse(res)
 
+    def test_preload_data(self):
+        store = new_data_store("file")
+        store_test = store.preload_data()
+        self.assertTrue(hasattr(store_test, "preload_handle"))
+        self.assertIsInstance(store_test.preload_handle, NullPreloadHandle)
+
 
 def test_fsspec_instantiation_error():
     error_string = "deliberate instantiation error for testing"

xcube/core/store/__init__.py

@@ -38,6 +38,7 @@
 from .store import (
     DataStore,
     MutableDataStore,
+    PreloadedDataStore,
     find_data_store_extensions,
     get_data_store_class,
     get_data_store_params_schema,

xcube/core/store/preload.py

@@ -75,11 +75,7 @@ def __repr__(self):
 
 
 class PreloadHandle(ABC):
-    """A handle for a preload job.
-
-    Instances of this class are returned by the
-    ``DataStore.preload_data()`` method.
-    """
+    """A handle for a preload job."""
 
     @abstractmethod
     def get_state(self, data_id: str) -> PreloadState:

xcube/core/store/store.py

@@ -28,7 +28,7 @@ def new_data_store(
     data_store_id: str,
     extension_registry: Optional[ExtensionRegistry] = None,
     **data_store_params,
-) -> Union["DataStore", "MutableDataStore"]:
+) -> Union["DataStore", "MutableDataStore", "PreloadDataStore"]:
     """Create a new data store instance for given
     *data_store_id* and *data_store_params*.
 
@@ -487,7 +487,7 @@ def preload_data(
         self,
         *data_ids: str,
         **preload_params: Any,
-    ) -> PreloadHandle:
+    ) -> "PreloadedDataStore":
         """Preload the given data items for faster access.
 
         Warning: This is an experimental and potentially unstable API
@@ -509,12 +509,11 @@ def preload_data(
               on the possible options.
 
         Returns:
-            A handle for the preload process. The default implementation
-            returns an empty preload handle.
+            A mutable data store containing the preload handle.
+            The default implementation contains an empty preload handle.
         """
-        return NullPreloadHandle()
-
-    # noinspection PyMethodMayBeStatic
+        self.preload_handle = NullPreloadHandle()
+        return self
 
 
 class MutableDataStore(DataStore, DataWriter, ABC):
@@ -690,3 +689,18 @@ def deregister_data(self, data_id: str):
         Raises:
             DataStoreError: If an error occurs.
         """
+
+
+class PreloadedDataStore(DataStore):
+    """A preload data store is a multable data store which contains the preload handle.
+
+    Instances of this class are returned by the ``DataStore.preload_data()`` method.
+    """
+
+    @property
+    @abstractmethod
+    def preload_handle(self) -> PreloadHandle:
+        """The preload handle that can be used to observe the preload progress.
+        Implementors of this interface may use a `ExecutorPreloadHandle` or consider
+        returning a `NullPreloadHandle` if the progress is not observable.
+        """

xcube/util/cache.py

@@ -439,9 +439,7 @@ def _compute_object_size(obj):
                 else (
                     3
                     if m in ("RGB", "YCbCr", "LAB", "HSV")
-                    else 1.0 / 8.0
-                    if m == "1"
-                    else 1
+                    else 1.0 / 8.0 if m == "1" else 1
                 )
             )
         )

xcube/util/dask.py

@@ -218,9 +218,7 @@ def new_cluster(
     cluster_account = (
         account
         if account is not None
-        else account_from_env_var
-        if account_from_env_var is not None
-        else "bc"
+        else account_from_env_var if account_from_env_var is not None else "bc"
     )
 
     if provider == "coiled":