issues: 1532317033

What happened?

While trying to load a .h5 file using load_dataset, I accidently specified the wrong path. Instead of getting a "no such file or directory" error, however, I got a "did not find a match in any of xarray's currently installed IO backends ['netcdf4']" error. It took some time to find out that the problem was actually with the path, and not with my installed software libraries.

What did you expect to happen?

I would expect that load_dataset informs me with a "no such file or directory" error, and not with something refering to the IO backends, if I attempt to open a file, that is clearly not existing. For .nc files this seems to work, see below.

Minimal Complete Verifiable Example

Python import xarray xarray.load_dataset('not-existing-file.h5')

MVCE confirmation

• [X] Minimal example — the example is as focused as reasonably possible to demonstrate the underlying issue in xarray.
• [X] Complete example — the example is self-contained, including all data and the text of any traceback.
• [X] Verifiable example — the example copy & pastes into an IPython prompt or Binder notebook, returning the result.
• [X] New issue — a search of GitHub Issues suggests this is not a duplicate.

Relevant log output

```Python

ValueError Traceback (most recent call last) Cell In[12], line 1 ----> 1 xarray.load_dataset('not-existing-file.h5')

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/api.py:279, in load_dataset(filename_or_obj, kwargs) 276 if "cache" in kwargs: 277 raise TypeError("cache has no effect in this context") --> 279 with open_dataset(filename_or_obj, kwargs) as ds: 280 return ds.load()

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/api.py:524, in open_dataset(filename_or_obj, engine, chunks, cache, decode_cf, mask_and_scale, decode_times, decode_timedelta, use_cftime, concat_characters, decode_coords, drop_variables, inline_array, backend_kwargs, **kwargs) 521 kwargs.update(backend_kwargs) 523 if engine is None: --> 524 engine = plugins.guess_engine(filename_or_obj) 526 backend = plugins.get_backend(engine) 528 decoders = _resolve_decoders_kwargs( 529 decode_cf, 530 open_backend_dataset_parameters=backend.open_dataset_parameters, (...) 536 decode_coords=decode_coords, 537 )

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/plugins.py:177, in guess_engine(store_spec) 169 else: 170 error_msg = ( 171 "found the following matches with the input file in xarray's IO " 172 f"backends: {compatible_engines}. But their dependencies may not be installed, see:\n" 173 "https://docs.xarray.dev/en/stable/user-guide/io.html \n" 174 "https://docs.xarray.dev/en/stable/getting-started-guide/installing.html" 175 ) --> 177 raise ValueError(error_msg)

ValueError: did not find a match in any of xarray's currently installed IO backends ['netcdf4']. Consider explicitly selecting one of the installed engines via the engine parameter, or installing additional IO dependencies, see: https://docs.xarray.dev/en/stable/getting-started-guide/installing.html https://docs.xarray.dev/en/stable/user-guide/io.html ```

Anything else we need to know?

It should be noted that the .h5 file is a working netcdf file, that can be loaded and used w/o installing further libraries if the path is correctly specified. Interestingly, for attempting to load a non existing .nc file, the load_dataset error message correctly says "FileNotFoundError: [Errno 2] No such file or directory: b'/home/jovyan/my_materials/not-existing-file.nc'".

Example code, python import xarray xarray.load_dataset('not-existing-file.nc')

Error message, ```

---

KeyError Traceback (most recent call last) File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/file_manager.py:209, in CachingFileManager._acquire_with_cache_info(self, needs_lock) 208 try: --> 209 file = self._cache[self._key] 210 except KeyError:

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/lru_cache.py:55, in LRUCache.getitem(self, key) 54 with self._lock: ---> 55 value = self._cache[key] 56 self._cache.move_to_end(key)

KeyError: [<class 'netCDF4._netCDF4.Dataset'>, ('/home/jovyan/my_materials/not-existing-file.nc',), 'r', (('clobber', True), ('diskless', False), ('format', 'NETCDF4'), ('persist', False)), 'ae3bbd85-042b-46e1-97ae-f8d523bb578a']

During handling of the above exception, another exception occurred:

FileNotFoundError Traceback (most recent call last) Cell In[11], line 1 ----> 1 xarray.load_dataset('not-existing-file.nc')

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/api.py:279, in load_dataset(filename_or_obj, kwargs) 276 if "cache" in kwargs: 277 raise TypeError("cache has no effect in this context") --> 279 with open_dataset(filename_or_obj, kwargs) as ds: 280 return ds.load()

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/api.py:540, in open_dataset(filename_or_obj, engine, chunks, cache, decode_cf, mask_and_scale, decode_times, decode_timedelta, use_cftime, concat_characters, decode_coords, drop_variables, inline_array, backend_kwargs, kwargs) 528 decoders = _resolve_decoders_kwargs( 529 decode_cf, 530 open_backend_dataset_parameters=backend.open_dataset_parameters, (...) 536 decode_coords=decode_coords, 537 ) 539 overwrite_encoded_chunks = kwargs.pop("overwrite_encoded_chunks", None) --> 540 backend_ds = backend.open_dataset( 541 filename_or_obj, 542 drop_variables=drop_variables, 543 decoders, 544 kwargs, 545 ) 546 ds = _dataset_from_backend_dataset( 547 backend_ds, 548 filename_or_obj, (...) 556 kwargs, 557 ) 558 return ds

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/netCDF4_.py:572, in NetCDF4BackendEntrypoint.open_dataset(self, filename_or_obj, mask_and_scale, decode_times, concat_characters, decode_coords, drop_variables, use_cftime, decode_timedelta, group, mode, format, clobber, diskless, persist, lock, autoclose) 551 def open_dataset( 552 self, 553 filename_or_obj, (...) 568 autoclose=False, 569 ): 571 filename_or_obj = _normalize_path(filename_or_obj) --> 572 store = NetCDF4DataStore.open( 573 filename_or_obj, 574 mode=mode, 575 format=format, 576 group=group, 577 clobber=clobber, 578 diskless=diskless, 579 persist=persist, 580 lock=lock, 581 autoclose=autoclose, 582 ) 584 store_entrypoint = StoreBackendEntrypoint() 585 with close_on_error(store):

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/netCDF4_.py:376, in NetCDF4DataStore.open(cls, filename, mode, format, group, clobber, diskless, persist, lock, lock_maker, autoclose) 370 kwargs = dict( 371 clobber=clobber, diskless=diskless, persist=persist, format=format 372 ) 373 manager = CachingFileManager( 374 netCDF4.Dataset, filename, mode=mode, kwargs=kwargs 375 ) --> 376 return cls(manager, group=group, mode=mode, lock=lock, autoclose=autoclose)

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/netCDF4_.py:323, in NetCDF4DataStore.init(self, manager, group, mode, lock, autoclose) 321 self._group = group 322 self._mode = mode --> 323 self.format = self.ds.data_model 324 self._filename = self.ds.filepath() 325 self.is_remote = is_remote_uri(self._filename)

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/netCDF4_.py:385, in NetCDF4DataStore.ds(self) 383 @property 384 def ds(self): --> 385 return self._acquire()

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/netCDF4_.py:379, in NetCDF4DataStore._acquire(self, needs_lock) 378 def _acquire(self, needs_lock=True): --> 379 with self._manager.acquire_context(needs_lock) as root: 380 ds = _nc4_require_group(root, self._group, self._mode) 381 return ds

File ~/my-pykernel/lib/python3.11/contextlib.py:137, in _GeneratorContextManager.enter(self) 135 del self.args, self.kwds, self.func 136 try: --> 137 return next(self.gen) 138 except StopIteration: 139 raise RuntimeError("generator didn't yield") from None

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/file_manager.py:197, in CachingFileManager.acquire_context(self, needs_lock) 194 @contextlib.contextmanager 195 def acquire_context(self, needs_lock=True): 196 """Context manager for acquiring a file.""" --> 197 file, cached = self._acquire_with_cache_info(needs_lock) 198 try: 199 yield file

File ~/my-pykernel/lib/python3.11/site-packages/xarray/backends/file_manager.py:215, in CachingFileManager._acquire_with_cache_info(self, needs_lock) 213 kwargs = kwargs.copy() 214 kwargs["mode"] = self._mode --> 215 file = self._opener(self._args, *kwargs) 216 if self._mode == "w": 217 # ensure file doesn't get overridden when opened again 218 self._mode = "a"

File src/netCDF4/_netCDF4.pyx:2463, in netCDF4._netCDF4.Dataset.init()

File src/netCDF4/_netCDF4.pyx:2026, in netCDF4._netCDF4._ensure_nc_success()

FileNotFoundError: [Errno 2] No such file or directory: b'/home/jovyan/my_materials/not-existing-file.nc' ```

Environment

INSTALLED VERSIONS ------------------ commit: None python: 3.11.0 | packaged by conda-forge | (main, Oct 25 2022, 06:24:40) [GCC 10.4.0] python-bits: 64 OS: Linux OS-release: 5.4.0-136-generic machine: x86_64 processor: x86_64 byteorder: little LC_ALL: None LANG: C.UTF-8 LOCALE: ('en_US', 'UTF-8') libhdf5: 1.12.2 libnetcdf: 4.8.1 xarray: 2022.12.0 pandas: 1.5.2 numpy: 1.24.1 scipy: None netCDF4: 1.6.2 pydap: None h5netcdf: None h5py: None Nio: None zarr: None cftime: 1.6.2 nc_time_axis: None PseudoNetCDF: None rasterio: None cfgrib: None iris: None bottleneck: None dask: None distributed: None matplotlib: None cartopy: None seaborn: None numbagg: None fsspec: None cupy: None pint: None sparse: None flox: None numpy_groupies: None setuptools: 65.6.3 pip: 22.3.1 conda: None pytest: None mypy: None IPython: 8.8.0 sphinx: None