Enable to parse more backend_kwargs when opening via PydapDataStore (e.g. output_grid)

[jgliss]

Is your feature request related to a problem?

I am planning to use xarray to access netcdf data from a thredds server. For my particular application, I need to be able to set pydap client option output_grid=False, to avoid some issues that I have experienced with a particular dataset on the server I am downloading from.

I use xarray.open_dataset to access the data via pydap backend, which currently only allows to specify "session" as a keyword in backend_kwargs.

xarray/xarray/backends/pydap_.py

Line 89 in 8c5c230

def open(cls, url, session=None):

It would be helpful to be able to provide additional backend_kwargs accepted by the pydap client (such as output_grid).

https://github.com/pydap/pydap/blob/dbe9b8d15831f21c28b97ed5661b2708faec45f2/src/pydap/client.py#L58

Describe the solution you'd like

It could be perhaps as simple as extending the signature of PydapDataStore.open from:

@classmethod
def open(cls, url, session=None):

    ds = pydap.client.open_url(url, session=session)
    return cls(ds)

to, e.g.:

@classmethod
def open(cls, url, **kwargs):

    ds = pydap.client.open_url(url, **kwargs)
    return cls(ds)

Describe alternatives you've considered

No response

Additional context

No response

[mathause]

That sounds reasonable - are you up to create a PR?

[jgliss]

That sounds reasonable - are you up to create a PR?

Yes, I can create a PR. Thanks for your fast reply.