Using ajax to post json data to a sinatra route and send to a database

Question

I am have some issues learning how JavaScript sends data around my application. Right now what I can't figure out is how to get some JSON data back to my Sintra POST route that creates a new database entry. I'm not really getting any error messages and my application shows the data on the screen but it never writes to the database.

Here is my latest unsuccessful attempt

With some alerts I've been able to determine that the JSON I'm sending looks like this

{"description":"test","created_at":"2014-09-25T10:31:29-04:00","updated_at":"2014-09-25T10:31:29-04:00"}

JavaScript Code

t.saveTask = function(task) {
  var t = ko.toJSON(task);
  $.ajax({
      type: "POST",
      url: "/tasks/new",
      dataType: 'json',         
      contentType: "application/json",          
      data:JSON.stringify(t)
  }).done(function(){
      alert (t);    
  });

Sintra Code

post "/tasks/new", :provides => :json do
    begin
      params = JSON.parse(request.env["rack.input"].read)
      @task = Task.new
      @task.complete = false
      @task.description = params[:description]
      @task.created_at = DateTime.now
      @task.updated_at = DateTime.now
      @task.save
    rescue Exception => e
      return e.message
    end

end

Answer 1

尝试在rescue前先@task.save ，我认为它丢失了。

Answer 2

Thanks everyone. I think I found a solution and I'm sure part of the problem was the @task.save. But in my efforts to fix the issue, I think I may have caused more issues. Here is my updated code that seems to work. Not sure why when I used ko.toJSON(task) it did not work, but with ko.toJS(task)

JavaScript Code

t.saveTask = function(task) {
  var t = ko.toJS(task);
  alert (t);
  $.ajax({
      type: "POST",
      url: "/tasks/new",       
      data: t
  }).done(function(){
      alert (t);    
  });

}

Sinatra Code

post "/tasks/new" do
      content_type :json
      @task = Task.new
      @task.complete = false
      @task.description = params[:description]
      @task.created_at = DateTime.now
      @task.updated_at = DateTime.now
      @task.save


end