add a sig grep command?

[ctb]

It'd be nice to be able to find signatures in files by md5... and also search by name, filename, etc.

ref #993

[ctb]

FWIW, this can be hacked together with picklists #1587, sourmash sig extract, and grep on picklists.

[ctb]

This is a handy command for taking e.g. a manifest or CSV output from sourmash sig describe and searching based on a name, to produce a picklist:

csvtk grep -p Campylobacter -r -f name all.csv > picklist.csv

the picklist can then be used with something like

sourmash sig extract --picklist picklist.csv:md5:md5 -o picked.zip

[ctb]

@bluegenes and I talked a bit in a teleconference about the idea of adding generic pattern matching for inclusion/exclusion of signatures from search, building off of picklists and manifests. Hot take UX:

sourmash gather --exclude GCA_0583288 ...
sourmash gather --include GCA_0583288 ...

this could be readily implemented as part of the picklist API.

(NOTE: moved to #1865)