Opening dataset without loading any indexes?

Is your feature request related to a problem?

Within pangeo-forge’s internals we would like to call open_dataset, then to_dict(), and end up with a schema-like representation of the contents of the dataset. This works, but it also has the side-effect of loading all indexes into memory, even if we are loading the data values “lazily”.

Describe the solution you’d like

@benbovy do you think it would be possible to (perhaps optionally) also avoid loading indexes upon opening a dataset, so that we actually don’t load anything? The end result would act a bit like ncdump does.

Describe alternatives you’ve considered

Otherwise we might have to try using xarray-schema or something but the suggestion here would be much neater and more flexible.

xref: https://github.com/pangeo-forge/pangeo-forge-recipes/issues/256

cc @rabernat @jhamman @cisaacstern

[rabernat]

Yes it is definitely a pathological example. 💣 But the fact remains that there are many cases where we just want to discover dataset contents as quickly as possible and want to avoid the cost of loading coordinates and creating indexes.

[dcherian]

This would also fix #2233