jquery - Rails Respond with JSON to show Flashes in Ajax -

i have following code:

my jobs.html.erb

  <div class="alert alert-error" style="display: none;"></div>   <p><%= link_to t("jobs.index.buttons.similar_functions"), user_email_settings_path, :class => "nice medium blue button", :id => "saveagent" %> <small id="agent-saved" style="font-size: 1em !important;display: none;"><%= t("jobs.index.saved_agent") %></small><br /></p> 

in page have following script:

  $("#saveagent").on('click', function (event) {     event.preventdefault();     $("#saveagent").addclass("disabled");     if( $("#saveagent").hasclass("disabled")) {           $.ajax({             type: 'post',             url: $(this).attr("href"),             data: $("form").serialize(),             complete: function() {               $("#agent-saved").show(1).delay(20000).fadeout(800);               $("#saveagent").removeclass("disabled");               alert("<%= flash[:error] %>");                 $('div.alert').show();                 $('div.alert').text("<%= flash[:error] %>");                 }           });     }   }); 

the link_to goes to email-settings_controller.rb has following code:

  def create     api_params = params[:criteria]     api_params = params[:criteria].reject{|k,v| v.to_s.blank?}      @j = jobagent.new(name_for_job_agent(current_user), true, api_params)     result = sap.submit_job_agent(@j.name, @j.to_xml, api_params_for_user)      parser = messageparser.new(result.body["result"])     parser.messages.each |message|       if message.type = "e"         flash[:error] = "test"         respond_to |format|           format.json { render :json => flash}         end       end     end   end 

now because it's ajax can't render flashes in normall way , have pass via json. code have seems works 50% of time returns correct "test" returns nothing.

is correct way of doing this? , how can work 100%.

thanks!

edit 1:

i'm trying following, found here : how send simple json response in rails?

def testme   respond_to |format|     msg = { :status => "ok", :message => "success!", :html => "<b>...</b>" }     format.json  { render :json => msg } # don't msg.to_json   end end 

but how read msg in complete function?

when use flash[:error] = '...', message consumed in next request, because syntax used before redirect_to.

in case need message immediately, because you're using render, should use instead:

flash.now[:error] = '...' 

see how works: http://guides.rubyonrails.org/action_controller_overview.html#the-flash