pulp file content upload: --chunk-size option should allow unit specifier in arg

[daviddavis]

From https://pulp.plan.io/issues/8838

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Following up from IRC, this:

pulp file content upload --chunk-size

currently takes a value whose unit is assumed to be bytes.

For larger values, it would be extremely useful to allow a unit to be specified, such as 'k', 'm', 'g' (or, if you think differentiating between powers of 10 vs powers of 2 is important, an alternate specifier). A simple approach might be to match nginx (that's how I ran into this, after modifying the client_max_body_size option). I'm new to pulp, so I don't know what other examples there are within pulp.

[mdellweg]

In the meantime, you can use shell arithmetic $((2**22))=4M.

[ggainey]

We do this in pulpcore/export for chunk_size - see https://github.com/pulp/pulpcore/blob/master/pulpcore/app/serializers/exporter.py#L218, based on https://stackoverflow.com/a/42865957/2002471

[ggainey]

I'm an idiot, pushed the wrong button.