Allow user handlers to take over bindings from builtin handlers.

- Fail if a user handler tries take a reserved binding.

2 files changed, 36 insertions, 1 deletions

diff --git a/config-model/src/main/java/com/yahoo/vespa/model/builder/xml/dom/DomHandlerBuilder.java b/config-model/src/main/java/com/yahoo/vespa/model/builder/xml/dom/DomHandlerBuilder.java
index d531569d287..45a044a2aa8 100644
--- a/config-model/src/main/java/com/yahoo/vespa/model/builder/xml/dom/DomHandlerBuilder.java
+++ b/config-model/src/main/java/com/yahoo/vespa/model/builder/xml/dom/DomHandlerBuilder.java
@@ -1,6 +1,7 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.vespa.model.builder.xml.dom;
 
+import com.yahoo.config.application.api.DeployLogger;
 import com.yahoo.config.model.deploy.DeployState;
 import com.yahoo.config.model.producer.AbstractConfigProducer;
 import com.yahoo.container.bundle.BundleInstantiationSpecification;
@@ -12,11 +13,16 @@ import com.yahoo.vespa.model.container.component.Handler;
 import com.yahoo.vespa.model.container.xml.BundleInstantiationSpecificationBuilder;
 import org.w3c.dom.Element;
 
+import java.util.Set;
+import static java.util.logging.Level.INFO;
+
 /**
  * @author gjoranv
  */
 public class DomHandlerBuilder extends VespaDomBuilder.DomConfigProducerBuilder<Handler> {
 
+    private static final Set<String> reservedBindings = Set.of();
+
     private final ApplicationContainerCluster cluster;
 
     public DomHandlerBuilder(ApplicationContainerCluster cluster) {
@@ -28,7 +34,7 @@ public class DomHandlerBuilder extends VespaDomBuilder.DomConfigProducerBuilder<
         Handler<? super Component<?, ?>> handler = createHandler(handlerElement);
 
         for (Element binding : XML.getChildren(handlerElement, "binding"))
-            handler.addServerBindings(XML.getValue(binding));
+            addServerBinding(handler, XML.getValue(binding), deployState.getDeployLogger());
 
         for (Element clientBinding : XML.getChildren(handlerElement, "clientBinding"))
             handler.addClientBindings(XML.getValue(clientBinding));
@@ -43,4 +49,29 @@ public class DomHandlerBuilder extends VespaDomBuilder.DomConfigProducerBuilder<
         return new Handler<>(new ComponentModel(bundleSpec));
     }
 
+    private void addServerBinding(Handler<? super Component<?, ?>> handler, String binding, DeployLogger log) {
+        throwIfBindingIsReserved(binding, handler);
+        handler.addServerBindings(binding);
+        removeExistingServerBinding(binding, handler, log);
+    }
+
+    private void throwIfBindingIsReserved(String binding, Handler<?> newHandler) {
+        for (var reserved : reservedBindings) {
+            if (binding.equals(reserved)) {
+                throw new IllegalArgumentException("Binding '" + binding + "' is a reserved Vespa binding and " +
+                                                           "cannot be used by handler: " + newHandler.getComponentId());
+            }
+        }
+    }
+
+    private void removeExistingServerBinding(String binding, Handler<?> newHandler, DeployLogger log) {
+        for (var handler : cluster.getHandlers()) {
+            if (handler.getServerBindings().contains(binding)) {
+                handler.removeServerBinding(binding);
+                log.log(INFO, "Binding '" + binding + "' was already in use by handler '" +
+                        handler.getComponentId() + "', but will now be taken over by handler: " + newHandler.getComponentId());
+            }
+        }
+    }
+
 }
diff --git a/config-model/src/main/java/com/yahoo/vespa/model/container/component/Handler.java b/config-model/src/main/java/com/yahoo/vespa/model/container/component/Handler.java
index fd1a03f13a8..82484e07773 100644
--- a/config-model/src/main/java/com/yahoo/vespa/model/container/component/Handler.java
+++ b/config-model/src/main/java/com/yahoo/vespa/model/container/component/Handler.java
@@ -42,6 +42,10 @@ public class Handler<CHILD extends AbstractConfigProducer<?>> extends Component<
         serverBindings.addAll(Arrays.asList(bindings));
     }
 
+    public void removeServerBinding(String binding) {
+        serverBindings.remove(binding);
+    }
+
     public void addClientBindings(String... bindings) {
         clientBindings.addAll(Arrays.asList(bindings));
     }