Communicate with Remote Servers

When you need to send data back and forth with a RESTful webservice or other backend server, you need a way to structure the data that you send and receive. In a previous age, ajax requests would send key-value pairs to webservices using query parameters or as form-encoded values in the body of a POST request. However, this gets really bulky when you need to send arrays and nested objects. Imagine trying to transmit these data via URL parameters: { “subscribe” : [ “peter” , “henrietta” , “xavier” ] } The resulting URL might look something like this: http://www.example.com/services/subscribe?subscribe[]=peter&subscribe[]=henrietta&subscribe[]=xavier Yuck. However, ajax requests are perfectly capable of sending JSON-encoded payloads within the body of a POST request, which is much cleaner. Here is an example of how to send a JSON-encoded POST body with the jQuery library: $.ajax({ “contentType”: “application/json”, “data”: ‘{“subscribe”: [“peter”, “henrietta”, “xavier”]}’, … }); Note that you have to send the JSON object as a string, since otherwise jQuery will invoke the object’s toString() method, and you’ll end up sending “[object Object]”, which is not particularly helpful! Just about every server-side language has a JSON library, so decoding the incoming request payload on the server side is trivial. Here are some resources for common server-side languages: C# Java PHP Python Ruby Don’t forget to have the remote service send back its response in JSON, too!