(brooklyn-server) 02/02: support prescanning entities for dynamic group

[heneveld]

This is an automated email from the ASF dual-hosted git repository.

heneveld pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/brooklyn-server.git

commit 6dd3bb6dddc1a8de721488b5aa0dc93dda083679
Author: Alex Heneveld <a...@cloudsoft.io>
AuthorDate: Mon Feb 19 09:56:51 2024 +0000

    support prescanning entities for dynamic group
    
    to see if there are changes
---
 .../org/apache/brooklyn/entity/group/DynamicGroup.java    |  2 ++
 .../apache/brooklyn/entity/group/DynamicGroupImpl.java    | 15 +++++++++++++--
 .../core/workflow/WorkflowConfigSensorEffectorTest.java   |  3 +++
 3 files changed, 18 insertions(+), 2 deletions(-)

diff --git 
a/core/src/main/java/org/apache/brooklyn/entity/group/DynamicGroup.java 
b/core/src/main/java/org/apache/brooklyn/entity/group/DynamicGroup.java
index a4fdace6a9..3e61ec80fc 100644
--- a/core/src/main/java/org/apache/brooklyn/entity/group/DynamicGroup.java
+++ b/core/src/main/java/org/apache/brooklyn/entity/group/DynamicGroup.java
@@ -70,6 +70,8 @@ public interface DynamicGroup extends AbstractGroup {
     /** Rescans <em>all</em> entities to determine whether they match the 
filter. */
     @Effector(description = "Rescans all entities to determine whether they 
match the configured filter.")
     void rescanEntities();
+    /** return true/false whether there are any changes detected */
+    boolean prescanEntities();
 
     /** Sets {@link #ENTITY_FILTER}, overriding (and rescanning all) if 
already set. */
     void setEntityFilter(Predicate<? super Entity> filter);
diff --git 
a/core/src/main/java/org/apache/brooklyn/entity/group/DynamicGroupImpl.java 
b/core/src/main/java/org/apache/brooklyn/entity/group/DynamicGroupImpl.java
index abeaaeeacf..b755b1f314 100644
--- a/core/src/main/java/org/apache/brooklyn/entity/group/DynamicGroupImpl.java
+++ b/core/src/main/java/org/apache/brooklyn/entity/group/DynamicGroupImpl.java
@@ -205,15 +205,23 @@ public class DynamicGroupImpl extends AbstractGroupImpl 
implements DynamicGroup
 
     @Override
     public void rescanEntities() {
+        rescanEntitiesInternal(true);
+    }
+
+    public boolean prescanEntities() {
+        return rescanEntitiesInternal(false);
+    }
+
+    protected boolean rescanEntitiesInternal(boolean makeChanges) {
         synchronized (memberChangeMutex) {
             if (!isRunning() || !getManagementSupport().isDeployed()) {
                 if (log.isDebugEnabled()) log.debug("{} not scanning for 
children: stopped", this);
-                return;
+                return false;
             }
             if (getAncestorToScan() == null) {
                 BrooklynLogging.log(log, 
BrooklynLogging.levelDependingIfReadOnly(this, LoggingLevel.WARN, 
LoggingLevel.TRACE, LoggingLevel.TRACE),
                     "{} not (yet) scanning for children: no application 
defined", this);
-                return;
+                return false;
             }
             boolean changed = false;
             Collection<Entity> currentMembers = getMembers();
@@ -225,17 +233,20 @@ public class DynamicGroupImpl extends AbstractGroupImpl 
implements DynamicGroup
                 toRemove.remove(it);
                 if (!currentMembers.contains(it)) {
                     if (log.isDebugEnabled()) log.debug("{} rescan detected 
new item {}", this, it);
+                    if (!makeChanges) return true;
                     addMember(it);
                     changed = true;
                 }
             }
             for (Entity it : toRemove) {
                 if (log.isDebugEnabled()) log.debug("{} rescan detected 
vanished item {}", this, it);
+                if (!makeChanges) return true;
                 removeMember(it);
                 changed = true;
             }
             if (changed && log.isDebugEnabled())
                 log.debug("{} rescan complete, members now {}", this, 
getMembers());
+            return changed;
         }
     }
 
diff --git 
a/core/src/test/java/org/apache/brooklyn/core/workflow/WorkflowConfigSensorEffectorTest.java
 
b/core/src/test/java/org/apache/brooklyn/core/workflow/WorkflowConfigSensorEffectorTest.java
index ea02bc12b0..d1b81f6231 100644
--- 
a/core/src/test/java/org/apache/brooklyn/core/workflow/WorkflowConfigSensorEffectorTest.java
+++ 
b/core/src/test/java/org/apache/brooklyn/core/workflow/WorkflowConfigSensorEffectorTest.java
@@ -194,6 +194,9 @@ public class WorkflowConfigSensorEffectorTest extends 
RebindTestFixture<TestAppl
         Entity chilld = Iterables.getOnlyElement(app.getChildren());
         Asserts.assertEquals(lastInvocation.getUnchecked(), chilld);
 
+        runWorkflow(MutableList.of("let entity x = "+chilld.getId(), "return 
${x}"));
+        Asserts.assertEquals(lastInvocation.getUnchecked(), chilld);
+
         runWorkflow(MutableList.of("let entity x = chilldx",
                         "let y = ${x} ?? missing",
                         "return ${y}"));