ActiveAdmin + Unicorn - Body yielded non-string value ERROR

[antonzaytsev]

I have unicorn (4.1.1) on my production server with latest active admin (0.3.4).
When I trying to open /admin I get this

E, [2011-12-09T02:24:42.155377 #22164] ERROR -- : app error: "Body yielded non-string value {all_active_admin_html_here}" (Rack::Lint::LintError)
E, [2011-12-09T02:24:42.155478 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@global/gems/rack-1.3.5/lib/rack/lint.rb:19:in 'assert'
E, [2011-12-09T02:24:42.155529 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@global/gems/rack-1.3.5/lib/rack/lint.rb:519:in 'block in each'
E, [2011-12-09T02:24:42.155563 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@global/gems/activerecord-3.1.2/lib/active_record/query_cache.rb:46:in 'each'
E, [2011-12-09T02:24:42.155596 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@global/gems/activerecord-3.1.2/lib/active_record/query_cache.rb:46:in 'each'
E, [2011-12-09T02:24:42.155628 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@global/gems/activerecord-3.1.2/lib/active_record/connection_adapters/abstract/connection_poion_pool.rb:458:in 'each'
E, [2011-12-09T02:24:42.155661 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@global/gems/rack-1.3.5/lib/rack/body_proxy.rb:23:in 'method_missing'
E, [2011-12-09T02:24:42.155694 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@global/gems/rack-1.3.5/lib/rack/lint.rb:517:in 'each'
E, [2011-12-09T02:24:42.155727 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@global/gems/rack-1.3.5/lib/rack/body_proxy.rb:23:in 'method_missing'
E, [2011-12-09T02:24:42.155759 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@affiliate/gems/unicorn-4.1.1/lib/unicorn/http_response.rb:41:in 'http_response_write'
E, [2011-12-09T02:24:42.155791 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@affiliate/gems/unicorn-4.1.1/lib/unicorn/http_server.rb:536:in 'process_client'
E, [2011-12-09T02:24:42.155824 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@affiliate/gems/unicorn-4.1.1/lib/unicorn/http_server.rb:600:in 'worker_loop'
E, [2011-12-09T02:24:42.155861 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@affiliate/gems/unicorn-4.1.1/lib/unicorn/http_server.rb:485:in 'spawn_missing_workers'
E, [2011-12-09T02:24:42.155894 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@affiliate/gems/unicorn-4.1.1/lib/unicorn/http_server.rb:135:in 'start'
E, [2011-12-09T02:24:42.155927 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@affiliate/gems/unicorn-4.1.1/bin/unicorn:121:in ''
E, [2011-12-09T02:24:42.155959 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@affiliate/bin/unicorn:19:in 'load'
E, [2011-12-09T02:24:42.155991 #22164] ERROR -- : /home/www/.rvm/gems/ruby-1.9.2-p290@affiliate/bin/unicorn:19:in ''

[antonzaytsev]

hm, no one who can help ?

[coreyti]

+1

same issue here.

[fmendez]

not sure if this could help, but I was having something similar : app error: Body yielded non-string value "avatar_url", "test". I figure that it had to do with what the http method being called (in this case was a call to a PUT ) was returning. I solve it by returning nil from the PUT method (i guess it would be the same for post). Hope this can help.

[antonzaytsev]

This comment really help me, hope it helps for other too #298 (comment)

Just use command unicorn_rails instead of unicorn to start server

[esad]

This is not really a solution. ActiveAdmin is not complying to Rack spec by not returning String objects but instead Arbre::Context objects.

I've opened a separate issue #1402 with more information