How to send data from client to server using Rikulo stream - dart

Question

I'm trying to use Rikulo stream, and i have some trouble when i want to send data from client to server.
Suppose that i have a registration form and i want send a request to check if that username already exist in my database.
I have adopted MVC pattern, so i want that the controller received data and then, using a dao class, check if username exist or not.
In client side i have this lines of code
InputElement username = query('#username');
document.query("#submit").onClick.listen((e) {
HttpRequest request = new HttpRequest();
var url = "/check-existing-username";
request.open("POST", url, async:true);
request.setRequestHeader("Content-Type", "application/json");
request.send(stringify({"user": username.value}));
});
Is this the correct way to send data?
Here my server side code
void main(){
Controller controller = new Controller();
var _mapping = {
"/": controller.home,
"/home": controller.home,
"/check-existing-username" : controller.checkUsername
};
new StreamServer(uriMapping: _mapping).start();
And my controller method
void checkUsername(HttpConnect connect) {
//How to access data received from client?
}
The dao class is already defined, so i want only know how to access data.
I hope that someone can help me.

Answer 1

Since you're using POST, the JSON data will be in the HTTP request's body. You can retrieve it there. Rikulo Commons has a utility called readAsJson. You can utilize it as follows.
import "package:rikulo_commons/convert.dart";
Future checkUsername(HttpConnect connect) {
return readAsJson(connect.request).then((Map<String, String> data) {
String username = data["user"];
//...doa...
});
}
Notice that reading request's body is asynchronous, so you have to return a Future instance to indicate when it is done.