no attribute 'LazilyIndexedArray'

[jrleeman]

Looks like a new Xarray version has broken master.

=================================== FAILURES ===================================
_____________________________ test_xarray_dataset ______________________________
    @recorder.use_cassette('rap_compressed')
    def test_xarray_dataset():
        """Test getting data using xarray open_dataset over CDMRemote."""
        store = CDMRemoteStore('http://thredds-dev.unidata.ucar.edu/thredds/cdmremote/'
                               'grib/NCEP/RAP/CONUS_13km/RR_CONUS_13km_20150518_1200.grib2/GC')
>       ds = open_dataset(store)
siphon/cdmr/tests/test_xarray.py:20: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
../../../virtualenv/python3.6.3/lib/python3.6/site-packages/xarray/backends/api.py:326: in open_dataset
    return maybe_decode_store(store)
../../../virtualenv/python3.6.3/lib/python3.6/site-packages/xarray/backends/api.py:238: in maybe_decode_store
    drop_variables=drop_variables)
../../../virtualenv/python3.6.3/lib/python3.6/site-packages/xarray/conventions.py:594: in decode_cf
    vars, attrs = obj.load()
../../../virtualenv/python3.6.3/lib/python3.6/site-packages/xarray/backends/common.py:217: in load
    for k, v in self.get_variables().items())
siphon/cdmr/xarray_support.py:54: in get_variables
    for k, v in self.ds.variables.items())
../../../virtualenv/python3.6.3/lib/python3.6/site-packages/xarray/core/utils.py:308: in FrozenOrderedDict
    return Frozen(OrderedDict(*args, **kwargs))
siphon/cdmr/xarray_support.py:54: in <genexpr>
    for k, v in self.ds.variables.items())
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
self = <siphon.cdmr.xarray_support.CDMRemoteStore object at 0x7f6b36eea6d8>
name = 'Geopotential_height_isobaric'
var = <siphon.cdmr.dataset.Variable object at 0x7f6b36ec0860>
    def open_store_variable(self, name, var):
        """Turn CDMRemote variable into something like a numpy.ndarray."""
>       data = indexing.LazilyIndexedArray(CDMArrayWrapper(name, self))
E       AttributeError: module 'xarray.core.indexing' has no attribute 'LazilyIndexedArray'
siphon/cdmr/xarray_support.py:48: AttributeError
==================== 1 failed, 289 passed in 137.13 seconds ====================

[jrleeman]

I can confirm that this works in Xarray 0.10.1, but not 0.10.2. Release notes didn't give up anything at first glance.

[dopplershift]

I think it's pydata/xarray#1899.

[fujiisoup]

Please rename LazilyIndexedArray to LazilyOuterIndexedArray.
We also updated indexing path for backend arrays (unwrap_explicit_indexer no longer exists).
Do something like this

def __getitem__(self, item):
    key, np_inds = indexing.decompose_indexer(
        key, self.shape, indexing.IndexingSupport.OUTER)
    with self.datastore.ensure_open(autoclose=True):
        array = self.get_array()[key.tuple]

    if len(np_inds.tuple) > 0:
        array = indexing.NumpyIndexingAdapter(array)[np_inds]

    return array

See an example backend wrapper
https://github.com/pydata/xarray/blob/a1fa397c48698b3434e513d480a8a2e8ad04dd58/xarray/backends/h5netcdf_.py#L18-L33

(Sorry for the inconvenience.)