package com.xmlcalabash.extensions;
import com.xmlcalabash.core.XProcConstants;
import com.xmlcalabash.core.XProcException;
import com.xmlcalabash.core.XProcRuntime;
import com.xmlcalabash.io.WritablePipe;
import com.xmlcalabash.library.DefaultStep;
import com.xmlcalabash.runtime.XAtomicStep;
import com.xmlcalabash.util.MessageFormatter;
import com.xmlcalabash.util.TreeWriter;
import net.sf.saxon.s9api.QName;
import net.sf.saxon.s9api.SaxonApiException;
import org.apache.http.Header;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpHead;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.impl.client.StandardHttpRequestRetryHandler;
import org.apache.http.impl.client.SystemDefaultHttpClient;
import org.apache.http.impl.cookie.DateParseException;
import org.apache.http.impl.cookie.DateUtils;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;
import java.io.File;
import java.io.IOException;
import java.net.URI;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.TimeZone;
/**
* Created by IntelliJ IDEA.
* User: ndw
* Date: Oct 8, 2008
* Time: 7:44:07 AM
* To change this template use File | Settings | File Templates.
*/
public class WaitForUpdate extends DefaultStep {
private static final QName _href = new QName("","href");
private static final QName _pause_before = new QName("","pause-before");
private static final QName _pause_after = new QName("","pause-after");
private static final long FILESYSTEM_WAIT = 100;
private static final long HTTP_WAIT = 1000;
private WritablePipe result = null;
private URI uri = null;
private long pauseBefore = 0;
private long pauseAfter = 0;
/**
* Creates a new instance of Identity
*/
public WaitForUpdate(XProcRuntime runtime, XAtomicStep step) {
super(runtime,step);
}
public void setOutput(String port, WritablePipe pipe) {
result = pipe;
}
public void reset() {
result.resetWriter();
}
public void run() throws SaxonApiException {
super.run();
String href = getOption(_href).getString();
URI baseURI = getOption(_href).getBaseURI();
URI uri = baseURI.resolve(href);
pauseBefore = getOption(_pause_before, (long) 0) * 1000;
pauseAfter = getOption(_pause_after, (long) 0) * 1000;
if (pauseBefore > 0) {
try {
Thread.sleep(pauseBefore);
} catch (InterruptedException ie) {
// I don't care
}
}
String changed = "";
if ("file".equals(uri.getScheme())) {
changed = waitForFile(uri);
} else if ("http".equals(uri.getScheme()) || "https".equals(uri.getScheme())) {
changed = waitForHttp(uri);
} else {
throw new XProcException("Only http: and file: URIs are supported on cx:wait-for-update");
}
if (pauseAfter > 0) {
try {
Thread.sleep(pauseAfter);
} catch (InterruptedException ie) {
// I don't care
}
}
TreeWriter tree = new TreeWriter(runtime);
tree.startDocument(step.getNode().getBaseURI());
tree.addStartElement(XProcConstants.c_result);
tree.startContent();
tree.addText(changed);
tree.addEndElement();
tree.endDocument();
result.write(tree.getResult());
}
private String waitForFile(URI uri) {
File f = new File(uri.getPath());
boolean newFile = false;
if (!f.exists()) {
newFile = true;
logger.debug(MessageFormatter.nodeMessage(step.getNode(), "Exist wait: " + f.getAbsolutePath()));
while (!f.exists()) {
try {
Thread.sleep(FILESYSTEM_WAIT);
} catch (InterruptedException ie) {
// I don't care
}
}
}
long dt = f.lastModified();
long cdt = dt;
if (!newFile) {
logger.debug(MessageFormatter.nodeMessage(step.getNode(), "Update wait: " + f.getAbsolutePath()));
while (cdt == dt) {
try {
Thread.sleep(FILESYSTEM_WAIT);
} catch (InterruptedException ie) {
// I don't care
}
cdt = f.lastModified();
}
}
Calendar cal = GregorianCalendar.getInstance();
TimeZone tz = TimeZone.getDefault();
long gmt = cdt - tz.getRawOffset();
if (tz.useDaylightTime() && tz.inDaylightTime(cal.getTime())) {
gmt -= tz.getDSTSavings();
}
cal.setTimeInMillis(gmt);
return String.format("%1$04d-%2$02d-%3$02dT%4$02d:%5$02d:%6$02dZ",
cal.get(Calendar.YEAR), cal.get(Calendar.MONTH)+1, cal.get(Calendar.DAY_OF_MONTH),
cal.get(Calendar.HOUR_OF_DAY), cal.get(Calendar.MINUTE), cal.get(Calendar.SECOND));
}
private String waitForHttp(URI uri) {
SystemDefaultHttpClient client = new SystemDefaultHttpClient();
client.setHttpRequestRetryHandler(new StandardHttpRequestRetryHandler(3, false));
HttpContext localContext = new BasicHttpContext();
HttpUriRequest httpRequest = new HttpHead(uri);
HttpResponse httpResponse = null;
httpResponse = head(client, httpRequest, localContext);
int statusCode = httpResponse.getStatusLine().getStatusCode();
String date = null;
boolean newUri = false;
if (statusCode == 404) {
newUri = true;
logger.debug(MessageFormatter.nodeMessage(step.getNode(), "Exist wait: " + uri.toASCIIString()));
while (statusCode == 404) {
try {
Thread.sleep(HTTP_WAIT); // one second
} catch (InterruptedException ie) {
// I don't care
}
httpResponse = head(client, httpRequest, localContext);
statusCode = httpResponse.getStatusLine().getStatusCode();
}
}
long dt = lastModified(httpResponse);
long cdt = dt;
if (statusCode == 200 && !newUri) {
logger.debug(MessageFormatter.nodeMessage(step.getNode(), "Update wait: " + uri.toASCIIString()));
while (statusCode == 200 && cdt == dt) {
try {
Thread.sleep(HTTP_WAIT);
} catch (InterruptedException ie) {
// I don't care
}
httpResponse = head(client, httpRequest, localContext);
statusCode = httpResponse.getStatusLine().getStatusCode();
cdt = lastModified(httpResponse);
}
}
Calendar cal = GregorianCalendar.getInstance();
TimeZone tz = TimeZone.getDefault();
long gmt = cdt - tz.getRawOffset();
if (tz.useDaylightTime() && tz.inDaylightTime(cal.getTime())) {
gmt -= tz.getDSTSavings();
}
cal.setTimeInMillis(gmt);
return String.format("%1$04d-%2$02d-%3$02dT%4$02d:%5$02d:%6$02dZ",
cal.get(Calendar.YEAR), cal.get(Calendar.MONTH)+1, cal.get(Calendar.DAY_OF_MONTH),
cal.get(Calendar.HOUR_OF_DAY), cal.get(Calendar.MINUTE), cal.get(Calendar.SECOND));
}
private long lastModified(HttpResponse httpResponse) {
String date = getHeader(httpResponse, "Last-modified", null);
if (date == null) {
date = getHeader(httpResponse, "Date", null);
}
try {
Date dt = DateUtils.parseDate(date);
return dt.getTime();
} catch (DateParseException dpe) {
// ignore
}
return GregorianCalendar.getInstance().getTimeInMillis();
}
private HttpResponse head(SystemDefaultHttpClient client, HttpUriRequest httpRequest, HttpContext localContext) {
try {
return client.execute(httpRequest, localContext);
} catch (ClientProtocolException cpe) {
throw new XProcException(cpe);
} catch (IOException ioe) {
throw new XProcException(ioe);
}
}
private String getHeader(HttpResponse resp, String name, String def) {
Header[] headers = resp.getHeaders(name);
if (headers == null) {
return def;
}
if (headers == null || headers.length == 0) {
// This should never happen
return def;
} else {
return headers[0].getValue();
}
}
}