org.cerberus.util.HTTPSession.java Source code

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Here is the source code for org.cerberus.util.HTTPSession.java

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/*
 * Cerberus  Copyright (C) 2013  vertigo17
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This file is part of Cerberus.
 *
 * Cerberus is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Cerberus is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Cerberus.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.cerberus.util;

import java.io.IOException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpException;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.HttpRequestInterceptor;
import org.apache.http.HttpResponse;
import org.apache.http.auth.AuthScheme;
import org.apache.http.auth.AuthScope;
import org.apache.http.auth.AuthState;
import org.apache.http.auth.Credentials;
import org.apache.http.auth.UsernamePasswordCredentials;
import org.apache.http.client.CredentialsProvider;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.params.ClientPNames;
import org.apache.http.client.protocol.ClientContext;
import org.apache.http.impl.auth.BasicScheme;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.ExecutionContext;
import org.apache.http.protocol.HttpContext;
import org.apache.http.util.EntityUtils;
import org.apache.log4j.Logger;

/**
 *
 * @author UDPI1
 */
public class HTTPSession {

    private static final Logger LOG = Logger.getLogger(HTTPSession.class);

    private DefaultHttpClient client;
    private BasicScheme basicAuth;
    private BasicHttpContext context;

    /**
     * Start a HTTP Session with authorisation
     *
     * @param username
     * @param password
     */
    public void startSession(String username, String password) {
        // Create your httpclient
        client = new DefaultHttpClient();
        client.getParams().setBooleanParameter(ClientPNames.ALLOW_CIRCULAR_REDIRECTS, true);

        // Then provide the right credentials
        client.getCredentialsProvider().setCredentials(new AuthScope(AuthScope.ANY_HOST, AuthScope.ANY_PORT),
                new UsernamePasswordCredentials(username, password));

        // Generate BASIC scheme object and stick it to the execution context
        basicAuth = new BasicScheme();
        context = new BasicHttpContext();
        context.setAttribute("preemptive-auth", basicAuth);

        // Add as the first (because of the zero) request interceptor
        // It will first intercept the request and preemptively initialize the authentication scheme if there is not
        client.addRequestInterceptor(new PreemptiveAuth(), 0);
    }

    /**
     * Start a HTTP Session without authorisation
     */
    public void startSession() {
        // Create your httpclient
        client = new DefaultHttpClient();
    }

    public void closeSession() {
        client.getConnectionManager().shutdown();
    }

    public int getURL(String url) {
        LOG.debug(url);
        HttpGet get = new HttpGet(url);
        HttpResponse response = null;
        HttpEntity entity = null;

        try {
            // Execute your request with the given context
            response = client.execute(get, context);
            entity = response.getEntity();
            EntityUtils.consume(entity);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        if (response != null && response.getStatusLine() != null) {
            return response.getStatusLine().getStatusCode();
        }
        return 0;
    }

    /**
     * Preemptive authentication interceptor
     *
     */
    static class PreemptiveAuth implements HttpRequestInterceptor {

        /*
         * (non-Javadoc)
         *
         * @see org.apache.http.HttpRequestInterceptor#process(org.apache.http.HttpRequest,
         * org.apache.http.protocol.HttpContext)
         */
        public void process(HttpRequest request, HttpContext context) throws HttpException, IOException {
            // Get the AuthState
            AuthState authState = (AuthState) context.getAttribute(ClientContext.TARGET_AUTH_STATE);

            // If no auth scheme available yet, try to initialize it preemptively
            if (authState.getAuthScheme() == null) {
                AuthScheme authScheme = (AuthScheme) context.getAttribute("preemptive-auth");
                CredentialsProvider credsProvider = (CredentialsProvider) context
                        .getAttribute(ClientContext.CREDS_PROVIDER);
                HttpHost targetHost = (HttpHost) context.getAttribute(ExecutionContext.HTTP_TARGET_HOST);
                if (authScheme != null) {
                    Credentials creds = credsProvider
                            .getCredentials(new AuthScope(targetHost.getHostName(), targetHost.getPort()));
                    if (creds == null) {
                        throw new HttpException("No credentials for preemptive authentication");
                    }
                    authState.setAuthScheme(authScheme);
                    authState.setCredentials(creds);
                }
            }

        }
    }
}