AsynchronousHttpClient

AsynchronousHttpClient.java

package org.deftserver.web.http.client;

import java.io.IOException;
import java.net.URL;
import java.nio.channels.SocketChannel;

import org.deftserver.io.AsynchronousSocket;
import org.deftserver.web.AsyncCallback;
import org.deftserver.web.AsyncResult;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class AsynchronousHttpClient {

	private static final Logger logger = LoggerFactory.getLogger(AsynchronousHttpClient.class);

	private AsynchronousSocket socket;

	public AsynchronousHttpClient() {
		try {
			socket = new AsynchronousSocket(SocketChannel.open().configureBlocking(false));
		} catch (IOException e) {
			logger.error("Error opening SocketChannel: {}" + e.getMessage());
		}
	}

	public void fetch(URL url, AsyncResult<HttpResponse> cb) {
		socket.connect(
				url.getHost(), 
				url.getPort(), 
				new AsyncCallback() { @Override public void onCallback() { onConnect(); }}
		);
		// TODO start a timer, if timeout => return "failure" to the client using the AHC else cancel timeout
	}

	public void close() {
		socket.close();
	}

	private void onConnect() {
		logger.debug("Connected...");
		socket.write(
				"GET / HTTP/1.0\r\nFrom: someuser@jmarshall.com\r\nUser-Agent: HTTPTool/1.0\r\n\r\n", 
				new AsyncCallback() { @Override public void onCallback() { onWriteComplete(); }}
		);
	}
	
	private void onWriteComplete() {
		logger.debug("onWriteComplete...");
		socket.readUntil(
				"\r\n", 
				new NaiveAsyncResult() { @Override public void onSuccess(String result) { onHeaders(result); }
		});
	}
	
	private void onHeaders(String headers) {
		logger.debug("result: {}", headers);
		// TODO read the rest of the body
	}
	
	/**
	 * Naive because all it does when an exception is thrown is log the exception.
	 */
	private static abstract class NaiveAsyncResult implements AsyncResult<String> {
		
		@Override
		public void onFailure(Throwable caught) {
			logger.debug("onFailure: {}", caught);
		}
		
	}


	
}