Issue #252: 500 error when repository is removed via commandline (conservancy/kallithea)

[Karl Goetz]

New issue 252: 500 error when repository is removed via commandline
https://bitbucket.org/conservancy/kallithea/issues/252/500-error-when-repository-is-removed-via

Karl Goetz:

Hi,
I just moved a repository from the kallithea repositories directory (website below) then ran Remap and Rescan with "Delete records of missing repositories" and "Invalidate cache for all repositories" ticked. I was expecting the repository to be deleted from Kallithea but I caused a 500 error instead:

```
Error - <class 'kallithea.lib.vcs.exceptions.VCSError'>: Given path /srv/kallithea/repositories/website is not a directory
URL: http://192.168.1.17:5000/_admin/settings/mapping
File '/srv/kallithea/environment/local/lib/python2.7/site-packages/weberror/errormiddleware.py', line 171 in __call__
  app_iter = self.application(environ, sr_checker)
File '/srv/kallithea/kallithea/kallithea/lib/middleware/sessionmiddleware.py', line 62 in __call__
  return self.wrap_app(environ, session_start_response)
File '/srv/kallithea/environment/local/lib/python2.7/site-packages/routes/middleware.py', line 131 in __call__
  response = self.app(environ, start_response)
File '/srv/kallithea/environment/local/lib/python2.7/site-packages/pylons/wsgiapp.py', line 103 in __call__
  response = self.dispatch(controller, environ, start_response)
File '/srv/kallithea/environment/local/lib/python2.7/site-packages/pylons/wsgiapp.py', line 313 in dispatch
  return controller(environ, start_response)
File '/srv/kallithea/kallithea/kallithea/lib/base.py', line 446 in __call__
  return WSGIController.__call__(self, environ, start_response)
File '/srv/kallithea/environment/local/lib/python2.7/site-packages/pylons/controllers/core.py', line 214 in __call__
  response = self._dispatch_call()
File '/srv/kallithea/environment/local/lib/python2.7/site-packages/pylons/controllers/core.py', line 164 in _dispatch_call
  response = self._inspect_call(func)
File '/srv/kallithea/environment/local/lib/python2.7/site-packages/pylons/controllers/core.py', line 107 in _inspect_call
  result = self._perform_call(func, args)
File '/srv/kallithea/environment/local/lib/python2.7/site-packages/pylons/controllers/core.py', line 57 in _perform_call
  return func(**args)
File '<decorator-gen-164>', line 2 in settings_mapping
File '/srv/kallithea/kallithea/kallithea/lib/auth.py', line 857 in __wrapper
  return func(*fargs, **fkwargs)
File '/srv/kallithea/kallithea/kallithea/controllers/admin/settings.py', line 209 in settings_mapping
  ScmModel().mark_for_invalidation(repo.repo_name, delete=True)
File '/srv/kallithea/kallithea/kallithea/model/scm.py', line 343 in mark_for_invalidation
  repo.update_changeset_cache()
File '/srv/kallithea/kallithea/kallithea/model/db.py', line 1343 in update_changeset_cache
  scm_repo = self.scm_instance_no_cache()
File '/srv/kallithea/kallithea/kallithea/model/db.py', line 1434 in scm_instance_no_cache
  return self.__get_instance()
File '/srv/kallithea/kallithea/kallithea/model/db.py', line 1461 in __get_instance
  alias = get_scm(safe_str(repo_full_path))[0]
File '/srv/kallithea/kallithea/kallithea/lib/vcs/utils/helpers.py', line 35 in get_scm
  raise VCSError("Given path %s is not a directory" % path)
VCSError: Given path /srv/kallithea/repositories/website is not a directory
```

On the fronted this generates the following error
```
500 Internal Server Error
The server encountered an unexpected condition which prevented it from fulfilling the request.
```