encode_cf_variable triggers AttributeError: 'DataArray' object has no attribute '_data'

[snowman2]

What happened?

AttributeError: 'DataArray' object has no attribute '_data'

What did you expect to happen?

No error.

Minimal Complete Verifiable Example

# https://github.com/corteva/rioxarray/blob/21284f67db536d9c104aa872ab0bbc261259e59e/test/integration/test_integration_rioxarray.py#L1818-L1844

import numpy
import xarray
import rioxarray

test_da = xarray.DataArray(
    numpy.zeros((5, 5)),
    dims=("y", "x"),
    coords={"y": numpy.arange(1, 6), "x": numpy.arange(2, 7)},
)
test_da.values[1, 1] = -1.1
test_nd = test_da.rio.write_nodata(-1.1)
test_nd.rio.write_transform(
    Affine.from_gdal(425047, 3.0, 0.0, 4615780, 0.0, -3.0), inplace=True
)
test_nd.rio.write_crs("EPSG:4326", inplace=True)
test_nd.rio.to_raster("dtype.tif", dtype=numpy.uint8)

MVCE confirmation

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

Relevant log output

rioxarray/raster_writer.py:288: in to_raster
    data = encode_cf_variable(out_data).values.astype(numpy_dtype)
/usr/share/miniconda/envs/test/lib/python3.9/site-packages/xarray/conventions.py:296: in encode_cf_variable
    var = coder.encode(var, name=name)
/usr/share/miniconda/envs/test/lib/python3.9/site-packages/xarray/coding/times.py:690: in encode
    ) or contains_cftime_datetimes(variable):
/usr/share/miniconda/envs/test/lib/python3.9/site-packages/xarray/core/common.py:1818: in contains_cftime_datetimes
    return _contains_cftime_datetimes(var._data)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = <xarray.DataArray (y: 5, x: 5)>
array([[ 0. ,  0. ,  0. ,  0. ,  0. ],
       [ 0. , -1.1,  0. ,  0. ,  0. ],
       [...    (y) int64 1 2 3 4 5
  * x            (x) int64 2 3 4 5 6
    spatial_ref  int64 0
Attributes:
    _FillValue:  -1.1
name = '_data'

    def __getattr__(self, name: str) -> Any:
        if name not in {"__dict__", "__setstate__"}:
            # this avoids an infinite loop when pickle looks for the
            # __setstate__ attribute before the xarray object is initialized
            for source in self._attr_sources:
                with suppress(KeyError):
                    return source[name]
>       raise AttributeError(
            f"{type(self).__name__!r} object has no attribute {name!r}"
        )
E       AttributeError: 'DataArray' object has no attribute '_data'

/usr/share/miniconda/envs/test/lib/python3.9/site-packages/xarray/core/common.py:276: AttributeError

Anything else we need to know?

No response

Environment

This is the latest version of xarray/numpy (pre-release versions).

https://github.com/corteva/rioxarray/actions/runs/4458288974/jobs/7829970587

[Illviljan]

Probably from #7494. encode_cf_variable only accepts Variables. Replace

data = encode_cf_variable(out_data).values.astype(numpy_dtype)

with

data = encode_cf_variable(out_data.variable).values.astype(numpy_dtype)

should fix the error.

mypy should have caught this a while ago when #7374 went in, does out_data have defined type hints?

[dcherian]

^ 👍

Passing .variable should fix it but the real issue here is that you're using private API because there is no public API: #4412

That would be a nice PR!

cc @JessicaS11 @scottyhq

[snowman2]

Thanks @Illviljan 👍

mypy should have caught this a while ago

Type hints are likely incomplete/inexact in some places in rioxarray code.