SDS client: improve flexibility of client.FMTSTR / _get_filename()

[megies]

Currently it is possible to re-use the SDS client for custom folder structures not following SDS schematics by replacing client.FMTSTR with some custom format string.. to some extent. Some things like e.g. "month" or "day of month" that people might use are not taken into consideration so it is not fully flexible.
People can still achieve full flexibility by subclassing sds.Client and overriding _get_filename with a custom routine, but maybe we could make it easier internally.

Kind of low priority though, since people can still achieve this.. although needing to subclass

[obspy-bot]

This issue has been mentioned on ObsPy Forum. There might be relevant details there:

https://discourse.obspy.org/t/request-client-for-specific-data-structure-archive-on-local-filesystem/1371/3

[ecastillot]

Thank you very much!
I follow your advices. Only one more thing. Also, you have to change _get_filenames function because it called _get_filename.

I posted this example in case anyone needs a help.
example

[d-chambers]

I am a little late to the party, but ObsPlus' WaveBank might also be useful for you. Depending on what you are trying to do, it will probably just work out of the box.