hudson.model.DownloadService Maven / Gradle / Ivy
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/*******************************************************************************
*
* Copyright (c) 2004-2009 Oracle Corporation.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
*
* Kohsuke Kawaguchi
*
*
*******************************************************************************/
package hudson.model;
import hudson.Extension;
import hudson.ExtensionList;
import hudson.ExtensionPoint;
import hudson.Functions;
import hudson.Util;
import hudson.util.IOUtils;
import hudson.util.QuotedStringTokenizer;
import hudson.util.TextFile;
import hudson.util.TimeUnit2;
import java.io.File;
import java.io.IOException;
import java.util.logging.Logger;
import net.sf.json.JSONObject;
import org.kohsuke.stapler.StaplerRequest;
import org.kohsuke.stapler.StaplerResponse;
/**
* Service for plugins to periodically retrieve update data files (like the one
* in the update center) through browsers.
*
* Because the retrieval of the file goes through XmlHttpRequest, we cannot
* reliably pass around binary.
*
* @author Kohsuke Kawaguchi
*/
@Extension
public class DownloadService extends PageDecorator {
public DownloadService() {
super(DownloadService.class);
}
/**
* Builds up an HTML fragment that starts all the download jobs.
*/
public String generateFragment() {
if (neverUpdate) {
return "";
}
StringBuilder buf = new StringBuilder();
if (Hudson.getInstance().hasPermission(Hudson.READ)) {
long now = System.currentTimeMillis();
for (Downloadable d : Downloadable.all()) {
if (d.getDue() < now && d.lastAttempt + 10 * 1000 < now) {
buf.append("");
d.lastAttempt = now;
}
}
}
return buf.toString();
}
/**
* Gets {@link Downloadable} by its ID. Used to bind them to URL.
*/
public Downloadable getById(String id) {
for (Downloadable d : Downloadable.all()) {
if (d.getId().equals(id)) {
return d;
}
}
return null;
}
/**
* Represents a periodically updated JSON data file obtained from a remote
* URL.
*
*
This mechanism is one of the basis of the update center, which
* involves fetching up-to-date data file.
*
* @since 1.305
*/
public static class Downloadable implements ExtensionPoint {
private final String id;
private final String url;
private final long interval;
private volatile long due = 0;
private volatile long lastAttempt = Long.MIN_VALUE;
/**
*
* @param url URL relative to {@link UpdateCenter#getUrl()}. So if this
* string is "foo.json", the ultimate URL will be something like
* "https://hudson-ci.org/update-center3.3.2/foo.json"
*
* For security and privacy reasons, we don't allow the retrieval from
* random locations.
*/
public Downloadable(String id, String url, long interval) {
this.id = id;
this.url = url;
this.interval = interval;
}
/**
* Uses the class name as an ID.
*/
public Downloadable(Class id) {
this(id.getName().replace('$', '.'));
}
public Downloadable(String id) {
this(id, id + ".json");
}
public Downloadable(String id, String url) {
this(id, url, TimeUnit2.DAYS.toMillis(1));
}
public String getId() {
return id;
}
/**
* URL to download.
*/
public String getUrl() {
return Hudson.getInstance().getUpdateCenter().getDefaultBaseUrl() + url;
}
/**
* How often do we retrieve the new image?
*
* @return number of milliseconds between retrieval.
*/
public long getInterval() {
return interval;
}
/**
* This is where the retrieved file will be stored.
*/
public TextFile getDataFile() {
return new TextFile(new File(Hudson.getInstance().getRootDir(), "updates/" + id));
}
/**
* When shall we retrieve this file next time?
*/
public long getDue() {
if (due == 0) // if the file doesn't exist, this code should result
// in a very small (but >0) due value, which should trigger
// the retrieval immediately.
{
due = getDataFile().file.lastModified() + interval;
}
return due;
}
/**
* Loads the current file into JSON and returns it, or null if no data
* exists.
*/
public JSONObject getData() throws IOException {
TextFile df = getDataFile();
if (df.exists()) {
return JSONObject.fromObject(df.read());
}
return null;
}
/**
* This is where the browser sends us the data.
*/
public void doPostBack(StaplerRequest req, StaplerResponse rsp) throws IOException {
long dataTimestamp = System.currentTimeMillis();
TextFile df = getDataFile();
df.write(IOUtils.toString(req.getInputStream(), "UTF-8"));
df.file.setLastModified(dataTimestamp);
due = dataTimestamp + getInterval();
LOGGER.info("Obtained the updated data file for " + id);
rsp.setContentType("text/plain"); // So browser won't try to parse response
}
/**
* Returns all the registered {@link Downloadable}s.
*/
public static ExtensionList all() {
return Hudson.getInstance().getExtensionList(Downloadable.class);
}
/**
* Returns the {@link Downloadable} that has the given ID.
*/
public static Downloadable get(String id) {
for (Downloadable d : all()) {
if (d.id.equals(id)) {
return d;
}
}
return null;
}
private static final Logger LOGGER = Logger.getLogger(Downloadable.class.getName());
}
public static boolean neverUpdate = Boolean.getBoolean(DownloadService.class.getName() + ".never");
}