ActionController known Format <p>I am having an issue with this code. It is for uploading an audio file. When I upload it I get an error saying this:</p> <pre><code>ActionController::UnknownFormat at /users/1/audios/dfdfdsdsf ============================================================ &gt; ActionController::UnknownFormat app/controllers/audios_controller.rb, line 67 --------------------------------------------- ``` ruby 62 if @audio.errors.empty? &amp;&amp; @audio.update_attributes(update_audio_params) 63 respond_to do |format| 64 format.html { redirect_to user_audios_path(@user) } 65 end 66 else &gt; 67 respond_to do |format| 68 format.html { render :edit } 69 format.js { render json: { result: :failed, errors: @audio.errors } } 70 end 71 end 72 end ``` App backtrace ------------- - app/controllers/audios_controller.rb:67:in `update' Full backtrace -------------- - actionpack (4.2.3) lib/action_controller/metal/mime_responds.rb:217:in `respond_to' - app/controllers/audios_controller.rb:67:in `update' - actionpack (4.2.3) lib/action_controller/metal/implicit_render.rb:4:in `send_action' - actionpack (4.2.3) lib/abstract_controller/base.rb:198:in `process_action' - actionpack (4.2.3) lib/action_controller/metal/rendering.rb:10:in `process_action' - actionpack (4.2.3) lib/abstract_controller/callbacks.rb:20:in `block in process_action' - activesupport (4.2.3) lib/active_support/callbacks.rb:115:in `call' - activesupport (4.2.3) lib/active_support/callbacks.rb:553:in `block (2 levels) in compile' - activesupport (4.2.3) lib/active_support/callbacks.rb:503:in `call' - activesupport (4.2.3) lib/active_support/callbacks.rb:88:in `run_callbacks' - actionpack (4.2.3) lib/abstract_controller/callbacks.rb:19:in `process_action' - actionpack (4.2.3) lib/action_controller/metal/rescue.rb:29:in `process_action' - actionpack (4.2.3) lib/action_controller/metal/instrumentation.rb:32:in `block in process_action' - activesupport (4.2.3) lib/active_support/notifications.rb:164:in `block in instrument' - activesupport (4.2.3) lib/active_support/notifications/instrumenter.rb:20:in `instrument' - activesupport (4.2.3) lib/active_support/notifications.rb:164:in `instrument' - actionpack (4.2.3) lib/action_controller/metal/instrumentation.rb:30:in `process_action' - actionpack (4.2.3) lib/action_controller/metal/params_wrapper.rb:250:in `process_action' - activerecord (4.2.3) lib/active_record/railties/controller_runtime.rb:18:in `process_action' - actionpack (4.2.3) lib/abstract_controller/base.rb:137:in `process' - actionview (4.2.3) lib/action_view/rendering.rb:30:in `process' - rack-mini-profiler (0.9.8) lib/mini_profiler/profiling_methods.rb:106:in `block in profile_method' - actionpack (4.2.3) lib/action_controller/metal.rb:196:in `dispatch' - actionpack (4.2.3) lib/action_controller/metal/rack_delegation.rb:13:in `dispatch' - actionpack (4.2.3) lib/action_controller/metal.rb:237:in `block in action' - actionpack (4.2.3) lib/action_dispatch/routing/route_set.rb:76:in `dispatch' - actionpack (4.2.3) lib/action_dispatch/routing/route_set.rb:45:in `serve' - actionpack (4.2.3) lib/action_dispatch/journey/router.rb:43:in `block in serve' - actionpack (4.2.3) lib/action_dispatch/journey/router.rb:30:in `serve' - actionpack (4.2.3) lib/action_dispatch/routing/route_set.rb:821:in `call' - warden (1.2.3) lib/warden/manager.rb:35:in `block in call' - warden (1.2.3) lib/warden/manager.rb:34:in `call' - rack (1.6.4) lib/rack/etag.rb:24:in `call' - rack (1.6.4) lib/rack/conditionalget.rb:38:in `call' - rack (1.6.4) lib/rack/head.rb:13:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/params_parser.rb:27:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/flash.rb:260:in `call' - rack (1.6.4) lib/rack/session/abstract/id.rb:225:in `context' - rack (1.6.4) lib/rack/session/abstract/id.rb:220:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/cookies.rb:560:in `call' - activerecord (4.2.3) lib/active_record/query_cache.rb:36:in `call' - activerecord (4.2.3) lib/active_record/connection_adapters/abstract/connection_pool.rb:653:in `call' - activerecord (4.2.3) lib/active_record/migration.rb:377:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/callbacks.rb:29:in `block in call' - activesupport (4.2.3) lib/active_support/callbacks.rb:84:in `run_callbacks' - actionpack (4.2.3) lib/action_dispatch/middleware/callbacks.rb:27:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/reloader.rb:73:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/remote_ip.rb:78:in `call' - better_errors (2.1.1) lib/better_errors/middleware.rb:84:in `protected_app_call' - better_errors (2.1.1) lib/better_errors/middleware.rb:79:in `better_errors_call' - better_errors (2.1.1) lib/better_errors/middleware.rb:57:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/debug_exceptions.rb:17:in `call' - web-console (2.2.1) lib/web_console/middleware.rb:39:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/show_exceptions.rb:30:in `call' - railties (4.2.3) lib/rails/rack/logger.rb:38:in `call_app' - railties (4.2.3) lib/rails/rack/logger.rb:20:in `block in call' - activesupport (4.2.3) lib/active_support/tagged_logging.rb:68:in `block in tagged' - activesupport (4.2.3) lib/active_support/tagged_logging.rb:26:in `tagged' - activesupport (4.2.3) lib/active_support/tagged_logging.rb:68:in `tagged' - railties (4.2.3) lib/rails/rack/logger.rb:20:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/request_id.rb:21:in `call' - rack (1.6.4) lib/rack/methodoverride.rb:22:in `call' - rack (1.6.4) lib/rack/runtime.rb:18:in `call' - activesupport (4.2.3) lib/active_support/cache/strategy/local_cache_middleware.rb:28:in `call' - rack (1.6.4) lib/rack/lock.rb:17:in `call' - actionpack (4.2.3) lib/action_dispatch/middleware/static.rb:116:in `call' - rack (1.6.4) lib/rack/sendfile.rb:113:in `call' - rack-mini-profiler (0.9.8) lib/mini_profiler/profiler.rb:282:in `call' - railties (4.2.3) lib/rails/engine.rb:518:in `call' - railties (4.2.3) lib/rails/application.rb:165:in `call' - rack (1.6.4) lib/rack/content_length.rb:15:in `call' - puma (2.12.2) lib/puma/server.rb:539:in `handle_request' - puma (2.12.2) lib/puma/server.rb:386:in `process_client' - puma (2.12.2) lib/puma/server.rb:269:in `block in run' - puma (2.12.2) lib/puma/thread_pool.rb:106:in `block in spawn_thread' </code></pre> <p>It might have to do with the respond_to block. Here is the code of that bellow:</p> <pre><code>def update if params[:audio][:attachment].blank? &amp;&amp; update_image_params.present? @audio.update_audio_cover_picture update_image_params["photo"] end if @audio.errors.empty? &amp;&amp; @audio.update_attributes(update_audio_params) respond_to do |format| format.html { redirect_to user_audios_path(@user) } end else respond_to do |format| format.html { render :edit } format.js { render json: { result: :failed, errors: @audio.errors } } end end end </code></pre> <p>This is a copy of the same code I use for my other project. It completely works on that app:</p> <pre><code>def update if params[:book][:attachment].blank? &amp;&amp; update_image_params.present? @book.update_book_cover_picture update_image_params["photo"] end if @book.errors.empty? &amp;&amp; @book.update_attributes(update_book_params) respond_to do |format| format.html { redirect_to user_books_path(@user) } format.json { render json: { result: :success, url: user_books_url(@user) } } end else respond_to do |format| format.html { render :edit } format.js { render json: { result: :failed, errors: @book.errors } } end end end </code></pre>