Deprecate v3 code on v2 branch

.github/workflows/minimal.yml

@@ -23,17 +23,17 @@ jobs:
     - name: Tests
       shell: "bash -l {0}"
       env:
-        ZARR_V3_EXPERIMENTAL_API: 1
-        ZARR_V3_SHARDING: 1
+        ZARR_V3_EXPERIMENTAL_API: 0
+        ZARR_V3_SHARDING: 0
       run: |
         conda activate minimal
         python -m pip install .
         pytest -svx --timeout=300
     - name: Fixture generation
       shell: "bash -l {0}"
       env:
-        ZARR_V3_EXPERIMENTAL_API: 1
-        ZARR_V3_SHARDING: 1
+        ZARR_V3_EXPERIMENTAL_API: 0
+        ZARR_V3_SHARDING: 0
       run: |
         conda activate minimal
         rm -rf fixture/

.github/workflows/python-package.yml

@@ -76,8 +76,8 @@ jobs:
         ZARR_TEST_ABS: 1
         ZARR_TEST_MONGO: 1
         ZARR_TEST_REDIS: 1
-        ZARR_V3_EXPERIMENTAL_API: 1
-        ZARR_V3_SHARDING: 1
+        ZARR_V3_EXPERIMENTAL_API: 0
+        ZARR_V3_SHARDING: 0
       run: |
         conda activate zarr-env
         mkdir ~/blob_emulator

.github/workflows/windows-testing.yml

@@ -50,8 +50,8 @@ jobs:
           pytest -sv --timeout=300
         env:
           ZARR_TEST_ABS: 1
-          ZARR_V3_EXPERIMENTAL_API: 1
-          ZARR_V3_SHARDING: 1
+          ZARR_V3_EXPERIMENTAL_API: 0
+          ZARR_V3_SHARDING: 0
       - name: Conda info
         shell: bash -l {0}
         run: conda info

docs/release.rst

@@ -23,6 +23,10 @@ Unreleased
 Deprecations
 ~~~~~~~~~~~~
 
+* Deprecated ``zarr._storage.v3`` and ``zarr._storage.v3_storage_transformers``.
+  This functionality and will be removed in ``zarr-python`` 2.19.0.
+  For Zarr format 3 support, use the v3 release of ``zarr-python``.
+  By :user:`David Stansby <dstansby>`
 * Deprecated support for ``partial_decompress`` when creating an array.
   This functionality is no longer supported in ``numcodecs``, and will be removed
   in ``zarr-python`` 2.19.0.

zarr/__init__.py

@@ -1,4 +1,5 @@
 # flake8: noqa
+import warnings
 from zarr.codecs import *
 from zarr.convenience import (
     consolidate_metadata,
@@ -55,6 +56,12 @@
 assert not __version__.startswith("0.0.0")
 
 if v3_api_available:
+    warnings.warn(
+        "The zarr v3 API in zarr-python v2 is deprecated, and will be removed in zarr-python 2.19.0. "
+        "Use zarr-python 3 instead for Zarr format 3 support.",
+        DeprecationWarning,
+        stacklevel=2,
+    )
     from zarr._storage.v3 import (
         ABSStoreV3,
         DBMStoreV3,

zarr/_storage/v3.py

@@ -1,3 +1,6 @@
+import warnings
+
+
 import os
 import shutil
 from collections import OrderedDict
@@ -49,6 +52,14 @@
     _getsize,
 )
 
+warnings.warn(
+    "zarr._storage.v3 is deprecated, and will be removed in zarr-python 2.19.0. "
+    "Use zarr-python 3 instead for Zarr format 3 support.",
+    DeprecationWarning,
+    stacklevel=2,
+)
+
+
 __doctest_requires__ = {
     ("RedisStore", "RedisStore.*"): ["redis"],
     ("MongoDBStore", "MongoDBStore.*"): ["pymongo"],

zarr/_storage/v3_storage_transformers.py

@@ -2,6 +2,7 @@
 import itertools
 import os
 from typing import NamedTuple, Tuple, Optional, Union, Iterator
+import warnings
 
 from numcodecs.compat import ensure_bytes
 import numpy as np
@@ -11,6 +12,14 @@
 from zarr.types import DIMENSION_SEPARATOR
 
 
+warnings.warn(
+    "zarr._storage.v3 is deprecated, and will be removed in zarr-python 2.19.0. "
+    "Use zarr-python 3 instead for Zarr format 3 support.",
+    DeprecationWarning,
+    stacklevel=2,
+)
+
+
 MAX_UINT_64 = 2**64 - 1
 
 

zarr/convenience.py

@@ -22,7 +22,11 @@
     BaseStore,
     ConsolidatedMetadataStore,
 )
-from zarr._storage.v3 import ConsolidatedMetadataStoreV3
+from zarr._storage.store import v3_api_available
+
+if v3_api_available:
+    from zarr._storage.v3 import ConsolidatedMetadataStoreV3
+
 from zarr.util import TreeViewer, buffer_size, normalize_storage_path
 
 from typing import Union

zarr/hierarchy.py

@@ -46,7 +46,11 @@
     rename,
     rmdir,
 )
-from zarr._storage.v3 import MemoryStoreV3
+from zarr._storage.store import v3_api_available
+
+if v3_api_available:
+    from zarr._storage.v3 import MemoryStoreV3
+
 from zarr.util import (
     InfoReporter,
     TreeViewer,
@@ -609,27 +613,33 @@
             for key in sorted(listdir(self._store, self._path)):
                 path = self._key_prefix + key
                 if contains_group(self._store, path, explicit_only=False):
-                    yield key, Group(
+                    yield (
+                        key,
+                        Group(
+                            self._store,
+                            path=path,
+                            read_only=self._read_only,
+                            chunk_store=self._chunk_store,
+                            cache_attrs=self.attrs.cache,
+                            synchronizer=self._synchronizer,
+                            zarr_version=self._version,
+                        ),
+                    )
+
+        else:
+            for key in self.group_keys():
+                path = self._key_prefix + key
+                yield (
+                    key,
+                    Group(
                         self._store,
                         path=path,
                         read_only=self._read_only,
                         chunk_store=self._chunk_store,
                         cache_attrs=self.attrs.cache,
                         synchronizer=self._synchronizer,
                         zarr_version=self._version,
-                    )
-
-        else:
-            for key in self.group_keys():
-                path = self._key_prefix + key
-                yield key, Group(
-                    self._store,
-                    path=path,
-                    read_only=self._read_only,
-                    chunk_store=self._chunk_store,
-                    cache_attrs=self.attrs.cache,
-                    synchronizer=self._synchronizer,
-                    zarr_version=self._version,
+                    ),
                 )
 
     def array_keys(self, recurse=False):

zarr/tests/test_attrs.py

@@ -7,21 +7,22 @@
 from zarr._storage.store import meta_root
 from zarr.attrs import Attributes
 from zarr.storage import KVStore, DirectoryStore
-from zarr._storage.v3 import KVStoreV3
-from zarr.tests.util import CountingDict, CountingDictV3
+
+
+from zarr.tests.util import CountingDict
 from zarr.hierarchy import group
 
+pytestmark = pytest.mark.filterwarnings("ignore:zarr.*v3 is deprecated:DeprecationWarning")
 
-@pytest.fixture(params=[2, 3])
+
+@pytest.fixture(params=[2])
 def zarr_version(request):
     return request.param
 
 
 def _init_store(version):
     """Use a plain dict() for v2, but KVStoreV3 otherwise."""
-    if version == 2:
-        return dict()
-    return KVStoreV3(dict())
+    return dict()
 
 
 class TestAttributes:
@@ -154,8 +155,8 @@ def test_caching_on(self, zarr_version):
         # caching is turned on by default
 
         # setup store
-        store = CountingDict() if zarr_version == 2 else CountingDictV3()
-        attrs_key = ".zattrs" if zarr_version == 2 else "meta/root/attrs"
+        store = CountingDict()
+        attrs_key = ".zattrs"
         assert 0 == store.counter["__getitem__", attrs_key]
         assert 0 == store.counter["__setitem__", attrs_key]
         if zarr_version == 2:
@@ -228,7 +229,7 @@ def test_caching_on(self, zarr_version):
 
     def test_caching_off(self, zarr_version):
         # setup store
-        store = CountingDict() if zarr_version == 2 else CountingDictV3()
+        store = CountingDict()
         attrs_key = ".zattrs" if zarr_version == 2 else "meta/root/attrs"
         assert 0 == store.counter["__getitem__", attrs_key]
         assert 0 == store.counter["__setitem__", attrs_key]