Sending HTTP Request in GWT

[Jinal P Shah]

Hello guys,
I'm new to GWT. I am trying to integrate Box.net in my GWT application but I am not able to send http request to Box.net. Please can any one tell me how do you send an http request and get a http response in GWT.

Regards

[Maneesh Godbole]

Welcome to the Ranch.

Check out RequestBuilder. More info here http://code.google.com/p/google-web-toolkit-doc-1-5/wiki/DevGuideHttpRequests

[Jinal P Shah]

Thanks for the reply. I tried that but it gives me an error Access-Control-Allow-Origin. So how do I resolve it?

Regards

[Maneesh Godbole]

The link I posted has information on the Same Origin Policy restrictions and possible workarounds. Did you refer to that?

[Jinal P Shah]

Yes, I saw the link and I did accordingly. I did sent the HttpRequest but now the problem is it does not get a response and I have no idea why is it so.
I can show you the code if you want and here is the link for my test
https://techchoice-2.appspot.com/
The Box-net Button is the one I am trying to implement.
See if you could help me for this.

Regards

[Maneesh Godbole]

is it does not get a response and I have no idea why is it so.

What is the response status code which you get back?

[Jinal P Shah]

I get the response code of 200 but I get an empty response. I have no idea why is it so?

[Maneesh Godbole]

200 indicates a successful call.
How are you checking the response?
What kind of response are you expecting from the server?

[Jinal P Shah]

200 indicates a successful call.

yaah 200 does indicate a successful execution but I still get an empty response.

How are you checking the response?
What kind of response are you expecting from the server?

I am using FireBug to check the response and I am expecting an XML response.

I am calling a rest service of Box.net and I am expecting an XML response from the api. But I am not getting it.

[Maneesh Godbole]

Please post the code where you build the request, make the call and process the response.

[Jinal P Shah]

Here is the code

package com.app.client.client;

import com.extjs.gxt.ui.client.event.ButtonEvent;
import com.extjs.gxt.ui.client.event.SelectionListener;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.http.client.*;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.TabPanel;

/**
 * Entry point classes define <code>onModuleLoad()</code>.
 */
@SuppressWarnings("unused")
public class WebApplication implements EntryPoint {
	/**
	 * The message displayed to the user when the server cannot be reached or
	 * returns an error.
	 */

	private static final String XML_LABEL_STYLE = "xmlLabel";
	public final String apiKey = "c4s9m9xeabg58fijervqgghsgkraoli8";
	
	public static final int STATUS_CODE_OK = 200;
	
	public static String token ="";
	
	private final GreetingServiceAsync greetingService = GWT
	.create(GreetingService.class);
	
	private static final String SERVER_ERROR = "An error occurred while "
			+ "attempting to contact the server. Please check your network "
			+ "connection and try again.";
	
	String url = "http://www.box.net/api/1.0/rest";
	
	String boxurl = "http://www.box.net/api/1.0/rest?action="+URL.encode("get_ticket")+"&api_key="+URL.encode("c4s9m9xeabg58fijervqgghsgkraoli8");
	
	final static Label errorLabel = new Label();
	/**
	 * Create a remote service proxy to talk to the server-side Greeting service.
	 */
	RequestBuilder builder = new RequestBuilder(RequestBuilder.GET, URL.encode(boxurl));
	/**
	 * This is the entry point method.
	 */
	native void boxcall() /*-{
	var url="https://www.box.net/api/1.0/rest?action=get_ticket&api_key=c4s9m9xeabg58fijervqgghsgkraoli8";
	  $.ajax({
        url:url,
    type: 'post',
    contentType:"application/x-www-form-urlencoded",
    data: '',
    success: function(data, status) {
        alert(data);
		var xml = data;
		var ticket = $(data).find('ticket').text();
		location.href = "https://www.box.net/api/1.0/auth/"+ticket;
        },
    error: function(xhr, desc, err) {
        alert("Error");
        }
    });
	}-*/;
	public void onModuleLoad() {
		try {
		final Button googleButton = new Button("Send");
		final Button boxButton = new Button("Box List");
		boxButton.addClickHandler(new ClickHandler() {
			
			public void onClick(ClickEvent event) {
				
				try {
					String requestData = null;
					//boxcall();
					//Window.Location.assign("https://www.box.net/api/1.0/auth/kloeu4ucypy8hxvise4pcm4kr4jymfef");
					//builder.setHeader("Content-Type", "text/html");
					//builder.setHeader("Access-Control-Allow-Origin","*" );
					builder.sendRequest(requestData, new RequestCallback() {	
						@Override
						public void onResponseReceived(Request request, Response response) {
							// TODO Auto-generated method stub
							if (200 == response.getStatusCode()) {
								renderXML(response.getText());
						      } else {
						    	  requestFailed(new Exception(response.getStatusText()+response.getStatusText()));
						      }	
							
						}
						
						@Override
						public void onError(Request request, Throwable exception) {
							// TODO Auto-generated method stub
							requestFailed(exception);
						}
					});
				} catch (Exception e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		});
		googleButton.setText("Google Access");
		if(com.google.gwt.user.client.Window.Location.getParameter("code") != null)
		{
		token = com.google.gwt.user.client.Window.Location.getParameter("code");
		
		}
		
		// We can add style names to widgets
		googleButton.addStyleName("sendButton");
		RootPanel.get("sendButtonContainer").add(googleButton);
		RootPanel.get("sendButtonContainer").add(boxButton);
		RootPanel.get("errorLabelContainer").add(errorLabel);
		

		// Create the popup dialog box
		
		com.extjs.gxt.ui.client.widget.button.Button b = new com.extjs.gxt.ui.client.widget.button.Button("Close", new SelectionListener<ButtonEvent>() {

		      @Override
		      public void componentSelected(ButtonEvent ce) {
		
		
			

		// get account file/folder tree structure
		String[] params = { "nozip", "simple" }; 
		      }

		    });
		

		
		// Create a handler for the sendButton and nameField
		class MyHandler implements ClickHandler {
			/**
			 * Fired when the user clicks on the sendButton.
			 */
			public void onClick(ClickEvent event) {
				try {
		            // get a ticket by API key.
		       // doPost("https://www.box.net/api/1.0/rest","action=get_ticket&api_key=c4s9m9xeabg58fijervqgghsgkraoli8");
		        //com.extjs.gxt.ui.client.widget.Label label = new com.extjs.gxt.ui.client.widget.Label("testing Label");
		        //w.add(label);
				//RootPanel.get().add(w);
				//w.show();
					com.google.gwt.user.client.Window.Location.assign("https://accounts.google.com/o/oauth2/auth?client_id=268740428731.apps.googleusercontent.com&redirect_uri=https://techchoice-2.appspot.com/&scope=https://docs.google.com/feeds/&response_type=code");
				}
				catch(Exception e)
				{
					errorLabel.setText(SERVER_ERROR);
				}
			}

			/**
			 * Fired when the user types in the nameField.
			 */
			

			
		}
		// Add a handler to send the name to the server
		MyHandler handler = new MyHandler();
		googleButton.addClickHandler(handler);
		 
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}  
		  
	}
	private void requestFailed(Throwable exception) {
		com.google.gwt.user.client.Window.alert("Failed to send the message: "
	        + exception.getMessage());
	}
	
	private void renderXML(String xmlText) {
	    final TabPanel tab = new TabPanel();
	    final FlowPanel xmlSource = new FlowPanel();
	    tab.add(xmlSource, "Details");
	    tab.selectTab(0);
	    RootPanel.get().add(tab);
	    xmlPane(xmlText, xmlSource);
	  }
	
	
	private void xmlPane(String xmlText, final FlowPanel xmlSource) {
	    xmlText = xmlText.replaceAll("<", "<");
	    xmlText = xmlText.replaceAll(">", ">");
	    Label xml = new HTML("<pre>" + xmlText + "</pre>", false);
	    xml.setStyleName(XML_LABEL_STYLE);
	    xmlSource.add(xml);
	  }
	
	
}