KeyError 'v' using Scene(base_dir=, reader=)

[howff]

Code Sample, a minimal, complete, and verifiable piece of code

global_scene = Scene(reader='viirs_sdr', base_dir='/data/viirs1/201801241307')

Problem description

Gives an error

   File "/packages/pytroll/local/lib/python2.7/site-packages/satpy/readers/__init__.py", line 398, in load_readers
   readers_files = set(filenames[reader[idx]])
KeyError: 'v'

There are four ways to initialise a Scene

1. base_dir='dir'
2. filenames=glob('dir/*.h5')
3. base_dir='dir, reader='viirs_sdr'
4. filenames=glob('dir/*.h5'), reader='viirs_sdr'

Option 3 is the one which fails with KeyError.

Versions of Python, package at hand and relevant dependencies

satpy 0.8.0

[mraspaud]

Yes, the basedir option is now removed since 0.8.0. I can't find a warning for this in the docs, so we have to fix this, and the error you get it not clear at all, but here is the recommended way of doing it now:
http://satpy.readthedocs.io/en/latest/readers.html#search-for-local-files

[djhoese]

The Scene.__init__ should have used the find_files_and_readers function internally along with a deprecation warning (agreed this is not documented well enough). My worry is that the find_files_and_readers function may be returning unexpected output (a single string when it should be a list of filenames).

[djhoese]

Good news? I get this same error with current master. I'll work on this today.