/* This program is free software: you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public License
as published by the Free Software Foundation, either version 3 of
the License, or (at your option) any later version.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>. */
package org.opentripplanner.updater.alerts;
import java.io.InputStream;
import java.util.prefs.Preferences;
import org.opentripplanner.routing.graph.Graph;
import org.opentripplanner.routing.impl.AlertPatchServiceImpl;
import org.opentripplanner.routing.services.AlertPatchService;
import org.opentripplanner.updater.GraphUpdaterManager;
import org.opentripplanner.updater.GraphWriterRunnable;
import org.opentripplanner.updater.PollingGraphUpdater;
import org.opentripplanner.util.HttpUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.transit.realtime.GtfsRealtime.FeedMessage;
/**
* GTFS-RT alerts updater
*
* Usage example ('myalert' name is an example) in file 'Graph.properties':
*
* <pre>
* myalert.type = real-time-alerts
* myalert.frequencySec = 60
* myalert.url = http://host.tld/path
* myalert.earlyStartSec = 3600
* myalert.defaultAgencyId = TA
* </pre>
*/
public class GtfsRealtimeAlertsUpdater extends PollingGraphUpdater {
private static final Logger LOG = LoggerFactory.getLogger(GtfsRealtimeAlertsUpdater.class);
private GraphUpdaterManager updaterManager;
private Long lastTimestamp = Long.MIN_VALUE;
private String url;
private String defaultAgencyId;
private AlertPatchService alertPatchService;
private long earlyStart;
private AlertsUpdateHandler updateHandler = null;
@Override
public void setGraphUpdaterManager(GraphUpdaterManager updaterManager) {
this.updaterManager = updaterManager;
}
@Override
protected void configurePolling(Graph graph, Preferences preferences) throws Exception {
// TODO: add options to choose different patch services
AlertPatchService alertPatchService = new AlertPatchServiceImpl(graph);
this.alertPatchService = alertPatchService;
String url = preferences.get("url", null);
if (url == null) {
throw new IllegalArgumentException("Missing mandatory 'url' parameter");
}
this.url = url;
this.earlyStart = preferences.getInt("earlyStartSec", 0);
this.defaultAgencyId = preferences.get("defaultAgencyId", null);
LOG.info("Creating real-time alert updater running every {} seconds : {}",
frequencySec, url);
}
@Override
public void setup() {
if (updateHandler == null) {
updateHandler = new AlertsUpdateHandler();
}
updateHandler.setEarlyStart(earlyStart);
updateHandler.setDefaultAgencyId(defaultAgencyId);
updateHandler.setAlertPatchService(alertPatchService);
}
@Override
protected void runPolling() {
try {
InputStream data = HttpUtils.getData(url);
if (data == null) {
throw new RuntimeException("Failed to get data from url " + url);
}
final FeedMessage feed = FeedMessage.PARSER.parseFrom(data);
long feedTimestamp = feed.getHeader().getTimestamp();
if (feedTimestamp <= lastTimestamp) {
LOG.info("Ignoring feed with an old timestamp.");
return;
}
// Handle update in graph writer runnable
updaterManager.execute(new GraphWriterRunnable() {
@Override
public void run(Graph graph) {
updateHandler.update(feed);
}
});
lastTimestamp = feedTimestamp;
} catch (Exception e) {
LOG.error("Error reading gtfs-realtime feed from " + url, e);
}
}
@Override
public void teardown() {
}
public String toString() {
return "GtfsRealtimeUpdater(" + url + ")";
}
}