/**
* *****************************************************************************
*
* 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.widgets;
import hudson.Functions;
import hudson.model.ModelObject;
import hudson.model.Run;
import org.kohsuke.stapler.Header;
import org.kohsuke.stapler.Stapler;
import org.kohsuke.stapler.StaplerRequest;
import org.kohsuke.stapler.StaplerResponse;
import javax.servlet.ServletException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
/**
* Displays the history of records (normally {@link Run}s) on the side panel.
*
* @param <O> Owner of the widget.
* @param <T> Type individual record.
* @author Kohsuke Kawaguchi
*/
public class HistoryWidget<O extends ModelObject, T> extends Widget {
/**
* The given data model of records. Newer ones first.
*/
//TODO: review and check whether we can do it private
public Iterable<T> baseList;
/**
* Indicates the next build number that client ajax should fetch.
*/
private String nextBuildNumberToFetch;
/**
* URL of the {@link #owner}.
*/
//TODO: review and check whether we can do it private
public final String baseUrl;
//TODO: review and check whether we can do it private
public final O owner;
private boolean trimmed;
//TODO: review and check whether we can do it private
public final Adapter<? super T> adapter;
/**
* First transient build record. Everything >= this will be discarded when
* AJAX call is made.
*/
private String firstTransientBuildKey;
/**
* @param owner The parent model object that owns this widget.
*/
public HistoryWidget(O owner, Iterable<T> baseList, Adapter<? super T> adapter) {
this.adapter = adapter;
this.baseList = baseList;
this.baseUrl = Functions.getNearestAncestorUrl(Stapler.getCurrentRequest(), owner);
this.owner = owner;
}
/**
* Title of the widget.
*/
public String getDisplayName() {
return Messages.BuildHistoryWidget_DisplayName();
}
@Override
public String getUrlName() {
return "buildHistory";
}
public String getFirstTransientBuildKey() {
return firstTransientBuildKey;
}
public Iterable<T> getBaseList() {
return baseList;
}
public String getBaseUrl() {
return baseUrl;
}
public O getOwner() {
return owner;
}
public Adapter<? super T> getAdapter() {
return adapter;
}
private Iterable<T> updateFirstTransientBuildKey(Iterable<T> source) {
String key = null;
for (T t : source) {
if (adapter.isBuilding(t)) {
key = adapter.getKey(t);
}
}
firstTransientBuildKey = key;
return source;
}
/**
* The records to be rendered this time.
*/
public Iterable<T> getRenderList() {
if (trimmed) {
List<T> lst;
if (baseList instanceof List) {
lst = (List<T>) baseList;
if (lst.size() > THRESHOLD) {
return updateFirstTransientBuildKey(lst.subList(0, THRESHOLD));
}
trimmed = false;
return updateFirstTransientBuildKey(lst);
} else {
lst = new ArrayList<T>(THRESHOLD);
Iterator<T> itr = baseList.iterator();
while (lst.size() <= THRESHOLD && itr.hasNext()) {
lst.add(itr.next());
}
trimmed = itr.hasNext(); // if we don't have enough items in the base list, setting this to false will optimize the next getRenderList() invocation.
return updateFirstTransientBuildKey(lst);
}
} else {
List<T> lst;
if (baseList instanceof List) {
lst = (List<T>) baseList;
} else {
lst = new ArrayList<T>();
Iterator<T> itr = baseList.iterator();
while (itr.hasNext()) {
lst.add(itr.next());
}
}
return updateFirstTransientBuildKey(lst);
}
}
public boolean isTrimmed() {
return trimmed;
}
public void setTrimmed(boolean trimmed) {
this.trimmed = trimmed;
}
/**
* Handles AJAX requests from browsers to update build history.
*
* @param n The build 'number' to fetch. This is string because various
* variants uses non-numbers as the build key.
*/
public void doAjax(StaplerRequest req, StaplerResponse rsp,
@Header("n") String n) throws IOException, ServletException {
rsp.setContentType("text/html;charset=UTF-8");
// pick up builds to send back
List<T> items = new ArrayList<T>();
if (n == null){
n = "0";
}
String nn = null; // we'll compute next n here
// list up all builds >=n.
for (T t : baseList) {
if (adapter.compare(t, n) >= 0) {
items.add(t);
if (adapter.isBuilding(t)) {
nn = adapter.getKey(t); // the next fetch should start from youngest build in progress
}
} else {
break;
}
}
if (nn == null) {
if (items.isEmpty()) {
// nothing to report back. next fetch should retry the same 'n'
nn = n;
} else {
// every record fetched this time is frozen. next fetch should start from the next build
nn = adapter.getNextKey(adapter.getKey(items.get(0)));
}
}
baseList = items;
rsp.setHeader("n", nn);
firstTransientBuildKey = nn; // all builds >= nn should be marked transient
req.getView(this, "ajaxBuildHistory.jelly").forward(req, rsp);
}
private static final int THRESHOLD = 30;
public String getNextBuildNumberToFetch() {
return nextBuildNumberToFetch;
}
public void setNextBuildNumberToFetch(String nextBuildNumberToFetch) {
this.nextBuildNumberToFetch = nextBuildNumberToFetch;
}
public interface Adapter<T> {
/**
* If record is newer than the key, return a positive number.
*/
int compare(T record, String key);
String getKey(T record);
boolean isBuilding(T record);
String getNextKey(String key);
}
}