Improve zarr version detection.

- Test zarr version, not Python version. Zarr *could* release a
  2.x that supports older Python verisons and breaks our indirect
  detection strategy.
- Test once and use a variable ZARR_LIB_V2 with the result,
  (inspired by pattern of using PY2 to detect Python 2).

Author: danielballan

tiled/_tests/test_container_fields.py

@@ -1,12 +1,11 @@
-import sys
-
 import anyio
 import h5py
 import numpy as np
 import pandas
 import pytest
 import zarr
 
+from ..adapters.zarr import ZARR_LIB_V2
 from ..catalog import in_memory
 from ..client import Context, from_context, record_history
 from ..client.register import register
@@ -84,7 +83,7 @@ def zarr_data_dir(tmpdir_factory):
     try:
         root = zarr.open(str(tmpdir / "zarr_group.zarr"), mode="w")
         for i, name in enumerate("abcde"):
-            if sys.version_info < (3, 11):
+            if ZARR_LIB_V2:
                 root.create_dataset(name, data=np.arange(i, i + 3))
             else:
                 root.create_array(name, data=np.arange(i, i + 3))

tiled/_tests/test_container_files.py

@@ -1,4 +1,3 @@
-import sys
 from pathlib import Path
 
 import h5py
@@ -7,6 +6,7 @@
 import pytest
 import zarr
 
+from ..adapters.zarr import ZARR_LIB_V2
 from ..catalog import in_memory
 from ..client import Context, from_context, tree
 from ..client.register import register
@@ -46,7 +46,7 @@ async def test_zarr_group(tmp_path: Path):
     x_array = np.array([1, 2, 3])
     y_array = np.array([4, 5, 6])
 
-    if sys.version_info < (3, 11):
+    if ZARR_LIB_V2:
         root.create_dataset("x", data=x_array)
         root.create_dataset("y", data=y_array)
     else:

tiled/adapters/zarr.py

@@ -1,21 +1,14 @@
 import builtins
 import copy
 import os
-import sys
 from collections.abc import Mapping
+from importlib.metadata import version
 from typing import Any, Iterator, List, Optional, Tuple, Union, cast
 from urllib.parse import quote_plus
 
 import zarr.core
-
-if sys.version_info < (3, 11):
-    from zarr.storage import DirectoryStore as LocalStore
-    from zarr.storage import init_array as create_array
-else:
-    from zarr.storage import LocalStore
-    from zarr import create_array
-
 from numpy._typing import NDArray
+from packaging.version import Version
 
 from ..adapters.utils import IndexersMixin
 from ..catalog.orm import Node
@@ -29,6 +22,14 @@
 from ..utils import Conflicts, node_repr, path_from_uri
 from .array import ArrayAdapter, slice_and_shape_from_block_and_chunks
 
+ZARR_LIB_V2 = Version(version("zarr")) < Version("3")
+if ZARR_LIB_V2:
+    from zarr.storage import DirectoryStore as LocalStore
+    from zarr.storage import init_array as create_array
+else:
+    from zarr import create_array
+    from zarr.storage import LocalStore
+
 INLINED_DEPTH = int(os.getenv("TILED_HDF5_INLINED_CONTENTS_MAX_DEPTH", "7"))