Also fixes wrong log message in allow_build.
Can you be very sure that self['brew']['build'] will not raise a KeyError? It would be a shame to hit a new traceback just as you were about to log another error.
self['brew']['build']
KeyError
One question about KeyError safety, but in general this looks good. :+1:
Why append an error message?
In case there were multiple error messages for given image, I want to be able to read them all and not just the last one ;).
We currently expect self['brew']['build'] in all other parts of code, but I have changed it in log_error to handle the situation when self['brew']['build'] is not here, why not :).
rebased onto 31f4a5c04da1b7074b877cfffd292ac109288e79
Commit ca505029 fixes this pull-request
Pull-Request has been merged by jkaluza
Also fixes wrong log message in allow_build.