AnalyticsTrackerUtil.java

/**
 * Copyright 2008 The University of North Carolina at Chapel Hill
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package edu.unc.lib.dl.ui.util;

import java.net.URI;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.List;

import javax.annotation.PreDestroy;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;

import org.apache.http.NameValuePair;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.utils.URIBuilder;
import org.apache.http.conn.HttpClientConnectionManager;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.message.BasicNameValuePair;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Utility for performing asynchronous analytics tracking events when unable to use the javascript api
 *
 * @author bbpennel
 * @date Apr 21, 2014
 */
public class AnalyticsTrackerUtil {

	private static final Logger log = LoggerFactory.getLogger(AnalyticsTrackerUtil.class);

	// Made up CID to use if the request does not include one, such as from a API request
	private static final String DEFAULT_CID = "35009a79-1a05-49d7-b876-2b884d0f825b";
	// Google analytics measurement API url
	private final String GA_URL = "https://www.google-analytics.com/collect";

	// Google analytics tracking id
	private String gaTrackingID;

	private final HttpClientConnectionManager httpManager;
	private final CloseableHttpClient httpClient;

	public AnalyticsTrackerUtil() {

		// Use a threaded manager with timeouts
		httpManager = new PoolingHttpClientConnectionManager();

		RequestConfig requestConfig = RequestConfig.custom()
				.setConnectTimeout(2000)
				.build();
		
		httpClient = HttpClients.custom()
				.setConnectionManager(httpManager)
				.setDefaultRequestConfig(requestConfig)
				.build();
	}

	@PreDestroy
	public void destroy() {
		httpManager.shutdown();
	}

	public void setGaTrackingID(String trackingID) {
		this.gaTrackingID = trackingID;
	}

	public void trackEvent(AnalyticsUserData userData, String category, String action, String label, Integer value) {

		// Use a default customer ID if none was provided, since it is required
		if (userData == null)
			return;

		// Perform the analytics tracking event asynchronously
		Thread trackerThread = new Thread(new EventTrackerRunnable(userData, category, action, label, value));
		trackerThread.start();
	}

	public static class AnalyticsUserData {
		public String uip;
		public String cid;

		public AnalyticsUserData(HttpServletRequest request) {

			// Get the user's IP address, either from proxy headers or request
			uip = request.getHeader("X-Forwarded-For");
			if (uip == null || uip.length() == 0 || "unknown".equalsIgnoreCase(uip)) {
				uip = request.getHeader("Proxy-Client-IP");
			}
			if (uip == null || uip.length() == 0 || "unknown".equalsIgnoreCase(uip)) {
				uip = request.getHeader("WL-Proxy-Client-IP");
			}
			if (uip == null || uip.length() == 0 || "unknown".equalsIgnoreCase(uip)) {
				uip = request.getHeader("HTTP_CLIENT_IP");
			}
			if (uip == null || uip.length() == 0 || "unknown".equalsIgnoreCase(uip)) {
				uip = request.getHeader("HTTP_X_FORWARDED_FOR");
			}
			if (uip == null || uip.length() == 0 || "unknown".equalsIgnoreCase(uip)) {
				uip = request.getRemoteAddr();
			}

			// Store the CID from _ga cookie if it is present
			Cookie cookies[] = request.getCookies();
			if (cookies != null) {
				for (Cookie cookie : cookies) {
					if ("_ga".equals(cookie.getName())) {
						String[] parts = cookie.getValue().split("\\.");
						if (parts.length == 4) {
							cid = parts[2] + "." + parts[3];
						}
						break;
					}
				}
			}

			if (cid == null) {
				cid = DEFAULT_CID;
			}

		}
	}

	private class EventTrackerRunnable implements Runnable {

		private final AnalyticsUserData userData;
		private final String category;
		private final String action;
		private final String label;
		private final Integer value;

		public EventTrackerRunnable(AnalyticsUserData userData, String category, String action, String label,
				Integer value) {
			this.category = category;
			this.action = action;
			this.label = label;
			this.value = value;
			this.userData = userData;
		}

		@Override
		public void run() {
			if (log.isDebugEnabled())
				log.debug("Tracking user {} with event {} in category {} with label {}",
						new String[] { userData.cid, action, category, label });

			URIBuilder builder;
			try {
				builder = new URIBuilder(GA_URL);
			} catch (URISyntaxException e) {
				log.warn("Failed to build URI for tracker", e);
				return;
			}
			
			List<NameValuePair> params = new ArrayList<NameValuePair>();
			params.add(new BasicNameValuePair("v", "1"));
			params.add(new BasicNameValuePair("tid", gaTrackingID));
			params.add(new BasicNameValuePair("cid", userData.cid));
			params.add(new BasicNameValuePair("t", "event"));
			params.add(new BasicNameValuePair("uip", userData.uip));
			params.add(new BasicNameValuePair("an", "cdr"));
			params.add(new BasicNameValuePair("de", "UTF-8"));
			params.add(new BasicNameValuePair("ul", "en-us"));
			log.debug("Tracking user {} with event {} in category {} with label {}",
					new String[] { userData.cid, action, category, label });
			log.debug("Tracking:{} {} {} {}", new Object[] { GA_URL, gaTrackingID, userData.cid, userData.uip});

			if (category != null) {
				params.add(new BasicNameValuePair("ec", category));
			}
			if (action != null) {
				params.add(new BasicNameValuePair("ea", action));
			}
			if (label != null) {
				params.add(new BasicNameValuePair("el", label));
			}
			if (value != null) {
				params.add(new BasicNameValuePair("ev", value.toString()));
			}
			
			builder.addParameters(params);
			
			HttpGet method;
			try {
				URI url = builder.build();
				method = new HttpGet(url);
				method.addHeader("Accept", "*/*");
			} catch (URISyntaxException e) {
				log.warn("Failed to build tracking url", e);
				return;
			}

			try (CloseableHttpResponse resp = httpClient.execute(method)) {
			} catch (Exception e) {
				log.warn("Failed to issue tracking event for cid {}", e, userData.cid);
			}
		}

	}
}