expose additional variables

core/src/main/java/hudson/WebAppMain.java

@@ -25,6 +25,7 @@ package hudson;
 
 import com.thoughtworks.xstream.converters.reflection.PureJavaReflectionProvider;
 import com.thoughtworks.xstream.core.JVM;
+import com.trilead.ssh2.util.IOUtils;
 import hudson.model.Hudson;
 import hudson.util.BootFailure;
 import jenkins.model.Jenkins;
@@ -53,15 +54,19 @@ import javax.servlet.ServletResponse;
 import javax.xml.transform.TransformerFactory;
 import javax.xml.transform.TransformerFactoryConfigurationError;
 import java.io.File;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.net.URL;
 import java.net.URLClassLoader;
+import java.util.Date;
 import java.util.Locale;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import java.security.Security;
 import java.util.logging.LogRecord;
 
+import static java.util.logging.Level.*;
+
 /**
  * Entry point when Hudson is used as a webapp.
  *
@@ -84,6 +89,7 @@ public final class WebAppMain implements ServletContextListener {
      */
     public void contextInitialized(ServletContextEvent event) {
         final ServletContext context = event.getServletContext();
+        File home=null;
         try {
 
             // use the current request to determine the language
@@ -111,7 +117,7 @@ public final class WebAppMain implements ServletContextListener {
             installLogger();
 
             final FileAndDescription describedHomeDir = getHomeDir(event);
-            final File home = describedHomeDir.file.getAbsoluteFile();
+            home = describedHomeDir.file.getAbsoluteFile();
             home.mkdirs();
             System.out.println("Jenkins home directory: "+home+" found at: "+describedHomeDir.description);
 
@@ -119,6 +125,8 @@ public final class WebAppMain implements ServletContextListener {
             if (!home.exists())
                 throw new NoHomeDir(home);
 
+            recordBootAttempt(home);
+
             // make sure that we are using XStream in the "enhanced" (JVM-specific) mode
             if(jvm.bestReflectionProvider().getClass()==PureJavaReflectionProvider.class) {
                 throw new IncompatibleVMDetected(); // nope
@@ -191,13 +199,13 @@ public final class WebAppMain implements ServletContextListener {
                 // if this works we are all happy
             } catch (TransformerFactoryConfigurationError x) {
                 // no it didn't.
-                LOGGER.log(Level.WARNING, "XSLT not configured correctly. Hudson will try to fix this. See http://issues.apache.org/bugzilla/show_bug.cgi?id=40895 for more details",x);
+                LOGGER.log(WARNING, "XSLT not configured correctly. Hudson will try to fix this. See http://issues.apache.org/bugzilla/show_bug.cgi?id=40895 for more details",x);
                 System.setProperty(TransformerFactory.class.getName(),"com.sun.org.apache.xalan.internal.xsltc.trax.TransformerFactoryImpl");
                 try {
                     TransformerFactory.newInstance();
                     LOGGER.info("XSLT is set to the JAXP RI in JRE");
                 } catch(TransformerFactoryConfigurationError y) {
-                    LOGGER.log(Level.SEVERE, "Failed to correct the problem.");
+                    LOGGER.log(SEVERE, "Failed to correct the problem.");
                 }
             }
 
@@ -205,22 +213,25 @@ public final class WebAppMain implements ServletContextListener {
 
             context.setAttribute(APP,new HudsonIsLoading());
 
+            final File _home = home;
             initThread = new Thread("Jenkins initialization thread") {
                 @Override
                 public void run() {
                     boolean success = false;
                     try {
-                        Jenkins instance = new Hudson(home, context);
+                        Jenkins instance = new Hudson(_home, context);
                         context.setAttribute(APP, instance);
 
+                        BootFailure.getBootFailureFile(_home).delete();
+
                         // at this point we are open for business and serving requests normally
                         LOGGER.info("Jenkins is fully up and running");
                         success = true;
                     } catch (Error e) {
-                        new HudsonFailedToLoad(e).publish(context);
+                        new HudsonFailedToLoad(e).publish(context,_home);
                         throw e;
                     } catch (Exception e) {
-                        new HudsonFailedToLoad(e).publish(context);
+                        new HudsonFailedToLoad(e).publish(context,_home);
                     } finally {
                         Jenkins instance = Jenkins.getInstance();
                         if(!success && instance!=null)
@@ -230,16 +241,34 @@ public final class WebAppMain implements ServletContextListener {
             };
             initThread.start();
         } catch (BootFailure e) {
-            e.publish(context);
+            e.publish(context,home);
         } catch (Error e) {
-            LOGGER.log(Level.SEVERE, "Failed to initialize Jenkins",e);
+            LOGGER.log(SEVERE, "Failed to initialize Jenkins",e);
             throw e;
         } catch (RuntimeException e) {
-            LOGGER.log(Level.SEVERE, "Failed to initialize Jenkins",e);
+            LOGGER.log(SEVERE, "Failed to initialize Jenkins",e);
             throw e;
         }
     }
 
+    /**
+     * To assist boot failure script, record the number of boot attempts.
+     * This file gets deleted in case of successful boot.
+     *
+     * @see BootFailure
+     */
+    private void recordBootAttempt(File home) {
+        FileOutputStream o=null;
+        try {
+            o = new FileOutputStream(BootFailure.getBootFailureFile(home), true);
+            o.write((new Date().toString() + System.getProperty("line.separator", "\n")).toString().getBytes());
+        } catch (IOException e) {
+            LOGGER.log(WARNING, "Failed to record boot attempts",e);
+        } finally {
+            IOUtils.closeQuietly(o);
+        }
+    }
+
     public static void installExpressionFactory(ServletContextEvent event) {
         JellyFacet.setExpressionFactory(event, new ExpressionFactory2());
     }

core/src/main/java/hudson/util/BootFailure.java

 package hudson.util;
 
+import hudson.WebAppMain;
 import jenkins.util.groovy.GroovyHookScript;
 import org.kohsuke.stapler.WebApp;
 
+import javax.annotation.CheckForNull;
 import javax.servlet.ServletContext;
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -11,6 +20,7 @@ import java.util.logging.Logger;
  * Indicates a fatal boot problem, among {@link ErrorObject}
  *
  * @author Kohsuke Kawaguchi
+ * @see WebAppMain#recordBootAttempt(File)
  */
 public abstract class BootFailure extends ErrorObject {
     protected BootFailure() {
@@ -22,15 +32,57 @@ public abstract class BootFailure extends ErrorObject {
 
     /**
      * Exposes this failure to UI and invoke the hook.
+     *
+     * @param home
+     *      JENKINS_HOME if it's already known.
      */
-    public void publish(ServletContext context) {
+    public void publish(ServletContext context, @CheckForNull File home) {
         LOGGER.log(Level.SEVERE, "Failed to initialize Jenkins",this);
 
         WebApp.get(context).setApp(this);
         new GroovyHookScript("boot-failure")
                 .bind("exception",this)
+                .bind("home",home)
+                .bind("servletContext", context)
+                .bind("attempts",loadAttempts(home))
                 .run();
     }
 
+    /**
+     * Parses the boot attempt file carefully so as not to cause the entire hook script to fail to execute.
+     */
+    protected List<Date> loadAttempts(File home) {
+        List<Date> dates = new ArrayList<Date>();
+        if (home!=null) {
+            File f = getBootFailureFile(home);
+            try {
+                if (f.exists()) {
+                    BufferedReader r = new BufferedReader(new FileReader(f));
+                    String line;
+                    while ((line=r.readLine())!=null) {
+                        try {
+                            dates.add(new Date(line));
+                        } catch (Exception e) {
+                            // ignore any parse error
+                        }
+                    }
+                }
+            } catch (IOException e) {
+                LOGGER.log(Level.WARNING,"Failed to parse "+f,e);
+            }
+        }
+        return dates;
+    }
+
     private static final Logger LOGGER = Logger.getLogger(BootFailure.class.getName());
+
+    /**
+     * This file captures failed boot attempts.
+     * Every time we try to boot, we add the timestamp to this file,
+     * then when we boot, the file gets deleted.
+     */
+    public static File getBootFailureFile(File home) {
+        return new File(home, "failed-boot-attempts.txt");
+    }
+
 }

core/src/main/java/jenkins/model/Jenkins.java

@@ -3086,7 +3086,7 @@ public class Jenkins extends AbstractCIBase implements ModifiableTopLevelItemGro
                     reload();
                 } catch (Exception e) {
                     LOGGER.log(SEVERE,"Failed to reload Jenkins config",e);
-                    new JenkinsReloadFailed(e).publish(servletContext);
+                    new JenkinsReloadFailed(e).publish(servletContext,root);
                 }
             }
         }.start();