issues: 942198905

Note: for upstream issue see https://github.com/dask/dask/issues/7887

What happened:

ds.to_zarr("s3://BUCKET/file.zarr") gives

What you expected to happen:

Finds AWS credentials and writes zarr object to AWS S3 cloud storage.

Minimal Complete Verifiable Example:

```python import xarray as xr

ds = xr.tutorial.open_dataset("air_temperature").isel(time=0) ds.to_zarr("s3://BUCKET/file.zarr")

---

ClientError Traceback (most recent call last) ~/opt/miniconda3/envs/main/lib/python3.9/site-packages/s3fs/core.py in _call_s3(self, method, akwarglist, kwargs) 245 try: --> 246 out = await method(*additional_kwargs) 247 return out

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/aiobotocore/client.py in _make_api_call(self, operation_name, api_params) 153 error_class = self.exceptions.from_code(error_code) --> 154 raise error_class(parsed_response, operation_name) 155 else:

ClientError: An error occurred (AccessDenied) when calling the PutObject operation: Access Denied

The above exception was the direct cause of the following exception:

PermissionError Traceback (most recent call last) ~/opt/miniconda3/envs/main/lib/python3.9/site-packages/zarr/storage.py in setitem(self, key, value) 1110 self.fs.rm(path, recursive=True) -> 1111 self.map[key] = value 1112 self.fs.invalidate_cache(self.fs._parent(path))

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/fsspec/mapping.py in setitem(self, key, value) 151 self.fs.mkdirs(self.fs._parent(key), exist_ok=True) --> 152 self.fs.pipe_file(key, maybe_convert(value)) 153

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/fsspec/asyn.py in wrapper(args, kwargs) 86 self = obj or args[0] ---> 87 return sync(self.loop, func, args, **kwargs) 88

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/fsspec/asyn.py in sync(loop, func, timeout, args, *kwargs) 67 if isinstance(result[0], BaseException): ---> 68 raise result[0] 69 return result[0]

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/fsspec/asyn.py in _runner(event, coro, result, timeout) 23 try: ---> 24 result[0] = await coro 25 except Exception as ex:

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/s3fs/core.py in _pipe_file(self, path, data, chunksize, kwargs) 865 if size < min(5 * 2 ** 30, 2 * chunksize): --> 866 return await self._call_s3( 867 "put_object", Bucket=bucket, Key=key, Body=data, kwargs

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/s3fs/core.py in _call_s3(self, method, akwarglist, *kwargs) 264 err = e --> 265 raise translate_boto_error(err) 266

PermissionError: Access Denied

The above exception was the direct cause of the following exception:

KeyError Traceback (most recent call last) /var/folders/rf/26llfhwd68x7cftb1z3h000w0000gp/T/ipykernel_10507/3272073269.py in <module> 1 ds = xr.tutorial.open_dataset("air_temperature").isel(time=0) ----> 2 ds.to_zarr("s3://BUCKET/file.zarr")

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/xarray/core/dataset.py in to_zarr(self, store, chunk_store, mode, synchronizer, group, encoding, compute, consolidated, append_dim, region, safe_chunks) 1920 encoding = {} 1921 -> 1922 return to_zarr( 1923 self, 1924 store=store,

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/xarray/backends/api.py in to_zarr(dataset, store, chunk_store, mode, synchronizer, group, encoding, compute, consolidated, append_dim, region, safe_chunks) 1432 ) 1433 -> 1434 zstore = backends.ZarrStore.open_group( 1435 store=store, 1436 mode=mode,

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/xarray/backends/zarr.py in open_group(cls, store, mode, synchronizer, group, consolidated, consolidate_on_close, chunk_store, storage_options, append_dim, write_region, safe_chunks) 336 zarr_group = zarr.open_consolidated(store, open_kwargs) 337 else: --> 338 zarr_group = zarr.open_group(store, open_kwargs) 339 return cls( 340 zarr_group, consolidate_on_close, append_dim, write_region, safe_chunks

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/zarr/hierarchy.py in open_group(store, mode, cache_attrs, synchronizer, path, chunk_store, storage_options) 1183 raise ContainsGroupError(path) 1184 else: -> 1185 init_group(store, path=path, chunk_store=chunk_store) 1186 1187 # determine read only status

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/zarr/storage.py in init_group(store, overwrite, path, chunk_store) 486 487 # initialise metadata --> 488 _init_group_metadata(store=store, overwrite=overwrite, path=path, 489 chunk_store=chunk_store) 490

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/zarr/storage.py in _init_group_metadata(store, overwrite, path, chunk_store) 513 meta = dict() # type: ignore 514 key = _path_to_prefix(path) + group_meta_key --> 515 store[key] = encode_group_metadata(meta) 516 517

~/opt/miniconda3/envs/main/lib/python3.9/site-packages/zarr/storage.py in setitem(self, key, value) 1112 self.fs.invalidate_cache(self.fs._parent(path)) 1113 except self.exceptions as e: -> 1114 raise KeyError(key) from e 1115 1116 def delitem(self, key):

KeyError: '.zgroup' ```