Change async in test based on zarr version - we can make this default behaviour too I think

Author: charles-turner-1

intake_esm/source.py

@@ -6,6 +6,7 @@
 import pandas as pd
 import pydantic
 import xarray as xr
+import zarr
 from intake.source.base import DataSource, Schema
 
 from .cat import Aggregation, DataFormat
@@ -20,6 +21,15 @@ class ESMDataSourceError(Exception):
     pass
 
 
+def _zarr_async() -> bool:
+    """
+    Zarr went all async in version 3.0.0. This sets the async flag based on
+    the zarr version in storage options
+    """
+
+    return int(zarr.__version__.split('.')[0]) > 2
+
+
 def _get_xarray_open_kwargs(data_format, xarray_open_kwargs=None, storage_options=None):
     xarray_open_kwargs = (xarray_open_kwargs or {}).copy()
     _default_open_kwargs = {

tests/test_source.py

@@ -14,6 +14,7 @@
     _get_xarray_open_kwargs,
     _open_dataset,
     _update_attrs,
+    _zarr_async,
 )
 
 dask.config.set(scheduler='single-threaded')
@@ -86,9 +87,10 @@ def test_open_dataset_kerchunk(kerchunk_file=kerchunk_file):
         dict(engine='zarr', consolidated=False),
         storage_options={
             'remote_protocol': 's3',
-            'remote_options': {'anon': True, 'asynchronous': True},
+            'remote_options': {'anon': True, 'asynchronous': _zarr_async()},
         },
     )
+
     ds = _open_dataset(
         data_format='reference',
         urlpath=kerchunk_file,