Neither foreman-proxy nor Foreman report on classes skipped during imports from Puppet. For example, this is the proxy.log from an Import operation where a new class added but contains syntax errors:

10.170.1.106 - - [20/Jan/2015 09:32:15] "GET /puppet/environments HTTP/1.1" 200 14 0.1917
10.170.1.106 - - [20/Jan/2015 09:32:16] "GET /puppet/environments/production/classes HTTP/1.1" 200 16616 1.1230

And this is the same operation from Foreman's production.log:

Started GET "/puppetclasses/import_environments?proxy=1-foreman" for *snip* at 2015-01-20 09:32:15 -0800
Processing by PuppetclassesController#import_environments as HTML
  Parameters: {"proxy"=>"1-foreman"}
  Rendered common/_puppetclasses_or_envs_changed.html.erb within layouts/application (3.7ms)
  Rendered home/_user_dropdown.html.erb (1.6ms)
Read fragment views/tabs_and_title_records-3 0.1ms
  Rendered home/_topbar.html.erb (2.4ms)
  Rendered layouts/base.html.erb (3.9ms)
Completed 200 OK in 1949.9ms (Views: 9.2ms | ActiveRecord: 40.1ms)
Started POST "/puppetclasses/obsolete_and_new" for 24.85.244.173 at 2015-01-20 09:32:19 -0800
Processing by PuppetclassesController#obsolete_and_new as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"*snip*", "changed"=>{"updated"=>{"production"=>"{\"essentials::hosts\":{\"obsolete\":[\"moo\"]}}"}}, "commit"=>"Update"}
Redirected to http://domain.com/puppetclasses

Please note that the "obsolete" class was one I created and deleted during testing. Foreman now reports that this class was removed during every import, despite the fact that was removed several import ago. It's irrelevant to this bug report.

I feel like this this operation should have either imported the new class in spite of its errors or else returned an error message. "200 OK" and a success message box reading "no changes detected" are not appropriate in this situation.