Actions can now override their rendering in the parent model object.

changelog.html

@@ -58,7 +58,6 @@ Upcoming changes</a>
 <!-- Record your changes in the trunk here. -->
 <div id="trunk" style="display:none"><!--=TRUNK-BEGIN=-->
 <ul class=image>
-  <li class=>
   <li class=bug>
     PAM authentication fails to restore group membership information on "remember me" tokens.
     (<a href="http://issues.jenkins-ci.org/browse/JENKINS-9094">issue 9094</a>)
@@ -66,6 +65,8 @@ Upcoming changes</a>
     Added an extension point to allow adding transient actions to computers.
   <li class=rfe>
     Added an extension point to allow associating custom properties with views.
+  <li class=rfe>
+    Actions can now override their rendering in the parent model object.
 </ul>
 </div><!--=TRUNK-END=-->
 

core/src/main/java/hudson/model/Action.java

@@ -39,6 +39,7 @@ import hudson.tasks.test.TestResultProjectAction;
  * while others do the former without the latter (for example, to just draw some graphs in <tt>floatingBox.jelly</tt>),
  * and still some others do both.
  *
+ * <h2>Views</h2>
  * <p>
  * If an action has a view named <tt>floatingBox.jelly</tt>,
  * it will be displayed as a floating box on the top page of
@@ -46,6 +47,19 @@ import hudson.tasks.test.TestResultProjectAction;
  * the JUnit test result trend shows up in the project top page.
  * See {@link TestResultProjectAction}.
  *
+ * <p>
+ * On the target {@link ModelObject} page, actions are rendered as an item in the side panel
+ * by the "/lib/hudson:actions" jelly tag, but you can override this for your action by
+ * writing {@code action.jelly}. See the "actions" tag for what the default handling is and
+ * tweak from there. One of the use cases of this is to show nested actions, like where
+ * Jenkins show the option to wipe out the workspace inside the workspace link:
+ *
+ * <pre>
+ * &lt;l:task icon="images/24x24/folder.gif"  href="${url}/ws/" title="${%Workspace}">
+ *   &lt;l:task icon="images/24x24/folder-delete.gif"  href="${url}/wipeOutWorkspace" title="${%Wipe Out Workspace}" />
+ * &lt;/l:task>
+ * </pre>
+ *
  * <h2>Persistence</h2>
  * <p>
  * Actions are often persisted as a part of {@link Actionable}

core/src/main/java/hudson/model/Hudson.java

@@ -2388,9 +2388,12 @@ public final class Hudson extends Node implements ItemGroup<TopLevelItem>, Stapl
     }
 
     public Object getDynamic(String token) {
-        for (Action a : getActions())
-            if(a.getUrlName().equals(token) || a.getUrlName().equals('/'+token))
+        for (Action a : getActions()) {
+            String url = a.getUrlName();
+            if (url==null)  continue;
+            if (url.equals(token) || url.equals('/' + token))
                 return a;
+        }
         for (Action a : getManagementLinks())
             if(a.getUrlName().equals(token))
                 return a;

core/src/main/resources/lib/hudson/actions.jelly

@@ -27,9 +27,12 @@ THE SOFTWARE.
 -->
 <j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form">
   <j:forEach var="action" items="${it.actions}">
-    <j:if test="${action.iconFileName!=null}">
-      <l:task icon="${h.getIconFilePath(action)}" title="${action.displayName}"
-              href="${h.getActionUrl(it.url,action)}" />
-    </j:if>
+    <!-- allow the action to take over the rendering, but otherwise fall back to the default -->
+    <st:include page="action.jelly" from="${action}" optional="true">
+      <j:if test="${action.iconFileName!=null}">
+        <l:task icon="${h.getIconFilePath(action)}" title="${action.displayName}"
+                href="${h.getActionUrl(it.url,action)}" />
+      </j:if>
+    </st:include>
   </j:forEach>
 </j:jelly>
\ No newline at end of file

test/src/test/java/lib/hudson/ActionsTest.java

+/*
+ * The MIT License
+ *
+ * Copyright (c) 2011, CloudBees, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lib.hudson;
+
+import hudson.model.InvisibleAction;
+import hudson.model.RootAction;
+import org.jvnet.hudson.test.HudsonTestCase;
+import org.jvnet.hudson.test.TestExtension;
+
+/**
+ * @author Kohsuke Kawaguchi
+ */
+public class ActionsTest extends HudsonTestCase {
+    public void testOverride() throws Exception {
+        assertNotNull(createWebClient().goTo("").getElementById("bravo"));
+    }
+
+    @TestExtension
+    public static class RootActionImpl extends InvisibleAction implements RootAction {
+    }
+}

test/src/test/resources/lib/hudson/ActionsTest/RootActionImpl/action.jelly

+<j:jelly xmlns:j="jelly:core">
+  <div>
+    <b id='bravo'>Bravo</b>
+  </div>
+</j:jelly>
\ No newline at end of file