PingbackPlugin.java [plain text]
package org.blojsom.plugin.pingback;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.xmlrpc.AsyncCallback;
import org.apache.xmlrpc.XmlRpcClient;
import org.blojsom.blog.BlogEntry;
import org.blojsom.blog.BlogUser;
import org.blojsom.blog.BlojsomConfiguration;
import org.blojsom.event.BlojsomEvent;
import org.blojsom.event.BlojsomListener;
import org.blojsom.plugin.BlojsomPlugin;
import org.blojsom.plugin.BlojsomPluginException;
import org.blojsom.plugin.admin.event.AddBlogEntryEvent;
import org.blojsom.plugin.admin.event.BlogEntryEvent;
import org.blojsom.plugin.admin.event.UpdatedBlogEntryEvent;
import org.blojsom.util.BlojsomConstants;
import org.blojsom.util.BlojsomUtils;
import javax.servlet.ServletConfig;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Map;
import java.util.Vector;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class PingbackPlugin implements BlojsomPlugin, BlojsomListener, BlojsomConstants {
private static Log _logger = LogFactory.getLog(PingbackPlugin.class);
private static final String PINGBACK_METHOD = "pingback.ping";
private static final String X_PINGBACK_HEADER = "X-Pingback";
private static final String PINGBACK_LINK_REGEX = "<link rel=\"pingback\" href=\"([^\"]+)\" ?/?>";
private static final String HREF_REGEX = "href\\s*=\\s*\"(.*?)\"";
public static final String PINGBACK_PLUGIN_METADATA_SEND_PINGBACKS = "send-pingbacks";
private PingbackPluginAsyncCallback _callbackHandler;
public PingbackPlugin() {
}
public void init(ServletConfig servletConfig, BlojsomConfiguration blojsomConfiguration) throws BlojsomPluginException {
_callbackHandler = new PingbackPluginAsyncCallback();
blojsomConfiguration.getEventBroadcaster().addListener(this);
_logger.debug("Initialized pingback plugin");
}
public BlogEntry[] process(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, BlogUser user, Map context, BlogEntry[] entries) throws BlojsomPluginException {
return entries;
}
public void cleanup() throws BlojsomPluginException {
}
public void destroy() throws BlojsomPluginException {
}
public void handleEvent(BlojsomEvent event) {
if (event instanceof AddBlogEntryEvent || event instanceof UpdatedBlogEntryEvent) {
BlogEntryEvent blogEntryEvent = (BlogEntryEvent) event;
String text = blogEntryEvent.getBlogEntry().getDescription();
if (!BlojsomUtils.checkNullOrBlank(text) && BlojsomUtils.checkMapForKey(blogEntryEvent.getBlogEntry().getMetaData(), PINGBACK_PLUGIN_METADATA_SEND_PINGBACKS)) {
String pingbackURL = null;
String sourceURI = blogEntryEvent.getBlogEntry().getLink();
String targetURI = null;
Pattern hrefPattern = Pattern.compile(HREF_REGEX, Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.UNICODE_CASE | Pattern.DOTALL);
Matcher hrefMatcher = hrefPattern.matcher(text);
_logger.debug("Checking for href's in entry: " + blogEntryEvent.getBlogEntry().getPermalink());
while (hrefMatcher.find()) {
targetURI = hrefMatcher.group(1);
_logger.debug("Found potential targetURI: " + targetURI);
try {
HttpURLConnection urlConnection = (HttpURLConnection) new URL(targetURI).openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
pingbackURL = urlConnection.getHeaderField(X_PINGBACK_HEADER);
if (pingbackURL == null) {
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream(), UTF8));
StringBuffer content = new StringBuffer();
String input;
while ((input = bufferedReader.readLine()) != null) {
content.append(input).append(LINE_SEPARATOR);
}
bufferedReader.close();
Pattern pingbackLinkPattern = Pattern.compile(PINGBACK_LINK_REGEX, Pattern.CASE_INSENSITIVE | Pattern.MULTILINE | Pattern.UNICODE_CASE | Pattern.DOTALL);
Matcher pingbackLinkMatcher = pingbackLinkPattern.matcher(content.toString());
if (pingbackLinkMatcher.find()) {
pingbackURL = pingbackLinkMatcher.group(1);
}
}
if (pingbackURL != null && targetURI != null) {
Vector parameters = new Vector();
parameters.add(sourceURI);
parameters.add(targetURI);
try {
_logger.debug("Sending pingback to: " + pingbackURL + " sourceURI: " + sourceURI + " targetURI: " + targetURI);
XmlRpcClient xmlRpcClient = new XmlRpcClient(pingbackURL);
xmlRpcClient.executeAsync(PINGBACK_METHOD, parameters, _callbackHandler);
} catch (MalformedURLException e) {
_logger.error(e);
}
}
} catch (IOException e) {
_logger.error(e);
}
}
} else {
_logger.debug("No text in blog entry or " + PINGBACK_PLUGIN_METADATA_SEND_PINGBACKS + " not enabled.");
}
}
}
public void processEvent(BlojsomEvent event) {
}
private class PingbackPluginAsyncCallback implements AsyncCallback {
public PingbackPluginAsyncCallback() {
}
public void handleResult(Object o, URL url, String s) {
_logger.debug(o.toString());
}
public void handleError(Exception e, URL url, String s) {
_logger.error(e);
}
}
}