From 2d3a028202d04a4edee80da4f4f32131af1d8c87 Mon Sep 17 00:00:00 2001
From: Andrew Azores <aazores@redhat.com>
Date: Fri, 10 Mar 2023 16:17:53 -0500
Subject: [PATCH] deregister builtin plugins if they are no longer
 available/selected

Signed-off-by: Andrew Azores <aazores@redhat.com>
---
 .../cryostat/discovery/BuiltInDiscovery.java  | 22 +++++++++++++++----
 .../cryostat/discovery/DiscoveryModule.java   | 11 ++++++++--
 .../io/cryostat/platform/PlatformModule.java  | 14 ++++++++++++
 3 files changed, 41 insertions(+), 6 deletions(-)

diff --git a/src/main/java/io/cryostat/discovery/BuiltInDiscovery.java b/src/main/java/io/cryostat/discovery/BuiltInDiscovery.java
index e0aa0a565b..628b297b73 100644
--- a/src/main/java/io/cryostat/discovery/BuiltInDiscovery.java
+++ b/src/main/java/io/cryostat/discovery/BuiltInDiscovery.java
@@ -41,6 +41,7 @@
 import java.util.Iterator;
 import java.util.Map;
 import java.util.Set;
+import java.util.SortedSet;
 import java.util.UUID;
 import java.util.function.Consumer;
 import java.util.stream.Stream;
@@ -62,7 +63,8 @@ public class BuiltInDiscovery extends AbstractVerticle implements Consumer<Targe
     static final String NOTIFICATION_CATEGORY = "TargetJvmDiscovery";
 
     private final DiscoveryStorage storage;
-    private final Set<PlatformDetectionStrategy<?>> platformStrategies;
+    private final Set<PlatformDetectionStrategy<?>> selectedStrategies;
+    private final Set<PlatformDetectionStrategy<?>> unselectedStrategies;
     private final Lazy<CustomTargetPlatformClient> customTargets;
     private final Set<PlatformClient> enabledClients = new HashSet<>();
     private final NotificationFactory notificationFactory;
@@ -70,12 +72,14 @@ public class BuiltInDiscovery extends AbstractVerticle implements Consumer<Targe
 
     BuiltInDiscovery(
             DiscoveryStorage storage,
-            Set<PlatformDetectionStrategy<?>> platformStrategies,
+            SortedSet<PlatformDetectionStrategy<?>> selectedStrategies,
+            SortedSet<PlatformDetectionStrategy<?>> unselectedStrategies,
             Lazy<CustomTargetPlatformClient> customTargets,
             NotificationFactory notificationFactory,
             Logger logger) {
         this.storage = storage;
-        this.platformStrategies = platformStrategies;
+        this.selectedStrategies = selectedStrategies;
+        this.unselectedStrategies = unselectedStrategies;
         this.customTargets = customTargets;
         this.notificationFactory = notificationFactory;
         this.logger = logger;
@@ -84,11 +88,21 @@ public class BuiltInDiscovery extends AbstractVerticle implements Consumer<Targe
     @Override
     public void start(Promise<Void> start) {
         storage.addTargetDiscoveryListener(this);
+
+        unselectedStrategies.stream()
+                .map(PlatformDetectionStrategy::getPlatformClient)
+                .forEach(
+                        platform ->
+                                storage.getBuiltInPluginByRealm(
+                                                platform.getDiscoveryTree().getName())
+                                        .map(PluginInfo::getId)
+                                        .ifPresent(storage::deregister));
+
         Stream.concat(
                         // ensure custom targets is always available regardless of other
                         // configurations
                         Stream.of(customTargets.get()),
-                        platformStrategies.stream()
+                        selectedStrategies.stream()
                                 .map(PlatformDetectionStrategy::getPlatformClient))
                 .distinct()
                 .forEach(
diff --git a/src/main/java/io/cryostat/discovery/DiscoveryModule.java b/src/main/java/io/cryostat/discovery/DiscoveryModule.java
index e2c5ab1513..8947ec6edc 100644
--- a/src/main/java/io/cryostat/discovery/DiscoveryModule.java
+++ b/src/main/java/io/cryostat/discovery/DiscoveryModule.java
@@ -119,12 +119,19 @@ static DiscoveryStorage provideDiscoveryStorage(
     static BuiltInDiscovery provideBuiltInDiscovery(
             DiscoveryStorage storage,
             @Named(PlatformModule.SELECTED_PLATFORMS)
-                    SortedSet<PlatformDetectionStrategy<?>> platformStrategies,
+                    SortedSet<PlatformDetectionStrategy<?>> selectedStrategies,
+            @Named(PlatformModule.UNSELECTED_PLATFORMS)
+                    SortedSet<PlatformDetectionStrategy<?>> unselectedStrategies,
             Lazy<CustomTargetPlatformClient> customTargets,
             NotificationFactory notificationFactory,
             Logger logger) {
         return new BuiltInDiscovery(
-                storage, platformStrategies, customTargets, notificationFactory, logger);
+                storage,
+                selectedStrategies,
+                unselectedStrategies,
+                customTargets,
+                notificationFactory,
+                logger);
     }
 
     @Provides
diff --git a/src/main/java/io/cryostat/platform/PlatformModule.java b/src/main/java/io/cryostat/platform/PlatformModule.java
index 35c8a1d551..c03526f37f 100644
--- a/src/main/java/io/cryostat/platform/PlatformModule.java
+++ b/src/main/java/io/cryostat/platform/PlatformModule.java
@@ -64,6 +64,7 @@
 public abstract class PlatformModule {
 
     public static final String SELECTED_PLATFORMS = "SELECTED_PLATFORMS";
+    public static final String UNSELECTED_PLATFORMS = "UNSELECTED_PLATFORMS";
 
     @Provides
     @Singleton
@@ -129,6 +130,19 @@ static SortedSet<PlatformDetectionStrategy<?>> provideSelectedPlatformStrategies
         return selectedStrategies;
     }
 
+    @Provides
+    @Singleton
+    @Named(UNSELECTED_PLATFORMS)
+    static SortedSet<PlatformDetectionStrategy<?>> provideUnselectedPlatformStrategies(
+            @Named(SELECTED_PLATFORMS) SortedSet<PlatformDetectionStrategy<?>> selectedStrategies,
+            Set<PlatformDetectionStrategy<?>> platformStrategies) {
+        SortedSet<PlatformDetectionStrategy<?>> unselected =
+                new TreeSet<>((a, b) -> Integer.compare(b.getPriority(), a.getPriority()));
+        unselected.addAll(platformStrategies);
+        unselected.removeAll(selectedStrategies);
+        return unselected;
+    }
+
     @Provides
     @Singleton
     static PlatformDetectionStrategy<?> providePlatformStrategy(