在rails应用程序中输出jSON

Question

ok, rails 3 new developer here.

I want my jquery to be able to get a json object from the rails 3 application for projects. Here is my controller.

def yourprojects
  @projects = Projects.all(current_user)

  respond_to do |format|
    format.html # index.html.erb
    format.json  { render :json => @projects }
  end
end

I added the format.json line... in jquery i have:

$.ajax({url: '/projects/yourprojects', dataType: 'json'});

So that should work i thought. Instead the server is returning: "Template is missing" "Missing template ,,,, with {:locale=>[:en, :en], :handlers=>[:rjs, :rhtml, :builder, :rxml, :erb], :formats=>[:html]} in view paths"

do you need a template for a jsOn return? shouldn't the rails 3 app know how to format the json?

Routes File:

resources :projects do
    collection do
        get 'yourprojects'  
    end
end

Answer 1

您可以为真实REST设置Accept: application/json标头，或者您可以将格式添加到URL以便快速解决：

$.ajax({url: '/projects/yourprojects.json', dataType: 'json'});

Answer 2

This is not issue of Rails but rather AJAX / jQuery not sending Accept header: Try this:

$.ajax({
   url: 'url_to_action', dataType: "json",
     beforeSend : function(xhr){
       xhr.setRequestHeader("Accept", "application/json")
     },
     success : function(data){
       //.. do something with data
     },
     error: function(objAJAXRequest, strError, errorThrown){
       alert("ERROR: " + strError);
     }
  }
);

If all your AJAX requests expect JSON, then you can set header globally:

$.ajaxSetup({
  dataType: 'json',
  'beforeSend' : function(xhr){
    xhr.setRequestHeader("Accept", "application/json")
  } 
});

Other option would be adding .json to path or data:{format: 'json'} to $.ajax hash of options. Rails supports format path suffixes by default for resoures routing. Just try rake routes to see.

Answer 3

:formats=>[:html]

That says the server is thinking that html is being requested. Try adding a .json to your path (and possible route) and that will force the format. TO make that would would need a route something like this:

map.your_projects '/projects/yourprojects.:format',
  :controller => 'projects',
  :action => 'yourprojects'

Somehow, someway, the params[:format] should be "json" for this request so the format handlers can do the right thing.