get_dataframe() crashes if 'id' is not included in ModelSerializer fields

[sheppard]

See http://paste.ubuntu.com/10862242/.

Currently the only way to get around this (short of adding id back to the included fields) is to subclass PandasSerializer and override get_index() to ensure it returns None (or any included field).

A better solution would be to have the default get_index() check for the id field before using it as the index, or to make it return None by default and always require it to be overridden for users that want an index to be set on their DataFrame.

[jsmedmar]

I like sheppard solution, another option would be to check for pk as well.