[incubator-kie-issues#1497] Using the getSerializableNodeInstances inside ProtobufProcessInstanceWriter

jbpm/jbpm-flow/src/main/java/org/jbpm/workflow/instance/node/CompositeNodeInstance.java

@@ -25,9 +25,11 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.UUID;
 import java.util.function.Function;
 import java.util.function.Predicate;
+import java.util.stream.Collectors;
 
 import org.jbpm.workflow.core.Node;
 import org.jbpm.workflow.core.node.CompositeNode;
@@ -54,7 +56,6 @@
 
 /**
  * Runtime counterpart of a composite node.
- * 
  */
 public class CompositeNodeInstance extends StateBasedNodeInstance implements NodeInstanceContainer, EventNodeInstanceInterface, EventBasedNodeInstanceInterface {
 
@@ -204,7 +205,12 @@ public void removeNodeInstance(final NodeInstance nodeInstance) {
 
     @Override
     public Collection<org.kie.api.runtime.process.NodeInstance> getNodeInstances() {
-        return new ArrayList<>(getNodeInstances(false));
+        return Collections.unmodifiableCollection(nodeInstances);
+    }
+
+    @Override
+    public Collection<org.kie.api.runtime.process.NodeInstance> getSerializableNodeInstances() {
+        return nodeInstances.stream().filter(this::isSerializable).collect(Collectors.toUnmodifiableList());
     }
 
     @Override
@@ -473,4 +479,24 @@ public Map<String, Integer> getIterationLevels() {
         return iterationLevels;
     }
 
+    /**
+     * Return a Set of classes that are not serializable
+     * Every subclass should override it, if needed, to avoid polluting the parent one (this) with children details
+     *
+     * @return
+     */
+    protected Set<Class<? extends org.kie.api.runtime.process.NodeInstance>> getNotSerializableClasses() {
+        return Collections.emptySet();
+    }
+
+    /**
+     * Check if the given <code>org.kie.api.runtime.process.NodeInstance</code> is serializable.
+     *
+     * @param toCheck
+     * @return
+     */
+    private boolean isSerializable(org.kie.api.runtime.process.NodeInstance toCheck) {
+        return !getNotSerializableClasses().contains(toCheck.getClass());
+    }
+
 }

jbpm/jbpm-flow/src/main/java/org/jbpm/workflow/instance/node/ForEachNodeInstance.java

@@ -26,6 +26,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.Set;
 
 import org.jbpm.process.core.ContextContainer;
 import org.jbpm.process.core.context.variable.VariableScope;
@@ -58,6 +59,8 @@
 public class ForEachNodeInstance extends CompositeContextNodeInstance {
 
     private static final long serialVersionUID = 510L;
+    private static final Set<Class<? extends org.kie.api.runtime.process.NodeInstance>> NOT_SERIALIZABLE_CLASSES = Set.of(ForEachJoinNodeInstance.class); // using Arrays.asList to allow multiple exclusions
+
     public static final String TEMP_OUTPUT_VAR = "foreach_output";
 
     private int totalInstances;
@@ -350,6 +353,11 @@ public int getLevelForNode(String uniqueID) {
         return 1;
     }
 
+    @Override
+    protected Set<Class<? extends org.kie.api.runtime.process.NodeInstance>> getNotSerializableClasses() {
+        return NOT_SERIALIZABLE_CLASSES;
+    }
+
     private class ForEachNodeInstanceResolverFactory extends NodeInstanceResolverFactory {
 
         private static final long serialVersionUID = -8856846610671009685L;

jbpm/jbpm-flow/src/test/java/org/jbpm/workflow/instance/node/ForEachNodeInstanceTest.java

@@ -0,0 +1,76 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.jbpm.workflow.instance.node;
+
+import java.util.Collection;
+import java.util.Set;
+
+import org.junit.jupiter.api.Test;
+import org.kie.api.runtime.process.NodeInstance;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class ForEachNodeInstanceTest {
+
+    @Test
+    void getNodeInstances() {
+        ForEachNodeInstance toTest = new ForEachNodeInstance();
+        CompositeNodeInstance compositeNodeInstance = new CompositeNodeInstance();
+        toTest.addNodeInstance(compositeNodeInstance);
+        Collection<NodeInstance> nodeInstances = toTest.getNodeInstances();
+        assertThat(nodeInstances)
+                .isNotNull()
+                .hasSize(1)
+                .contains(compositeNodeInstance);
+        ForEachNodeInstance.ForEachJoinNodeInstance forEachJoinNodeInstance = toTest.new ForEachJoinNodeInstance();
+        toTest.addNodeInstance(forEachJoinNodeInstance);
+        nodeInstances = toTest.getNodeInstances();
+        assertThat(nodeInstances)
+                .isNotNull()
+                .hasSize(2)
+                .contains(compositeNodeInstance, forEachJoinNodeInstance);
+    }
+
+    @Test
+    void getSerializableNodeInstances() {
+        ForEachNodeInstance toTest = new ForEachNodeInstance();
+        CompositeNodeInstance compositeNodeInstance = new CompositeNodeInstance();
+        toTest.addNodeInstance(compositeNodeInstance);
+        Collection<NodeInstance> serializableNodeInstances = toTest.getSerializableNodeInstances();
+        assertThat(serializableNodeInstances)
+                .isNotNull()
+                .hasSize(1)
+                .contains(compositeNodeInstance);
+        ForEachNodeInstance.ForEachJoinNodeInstance forEachJoinNodeInstance =  toTest.new ForEachJoinNodeInstance();
+        toTest.addNodeInstance(forEachJoinNodeInstance);
+        serializableNodeInstances = toTest.getSerializableNodeInstances();
+        assertThat(serializableNodeInstances)
+                .isNotNull()
+                .hasSize(1)
+                .contains(compositeNodeInstance);
+    }
+
+    @Test
+    void getNotSerializableClasses() {
+        Set<Class<? extends NodeInstance>> retrieved = new ForEachNodeInstance().getNotSerializableClasses();
+        assertThat(retrieved).isNotNull()
+                .hasSize(1)
+                .allMatch(cls -> cls.equals(ForEachNodeInstance.ForEachJoinNodeInstance.class));
+    }
+}

jbpm/process-serialization-protobuf/src/main/java/org/jbpm/flow/serialization/impl/ProtobufProcessInstanceWriter.java

@@ -249,7 +249,7 @@ public FieldDescriptor getContextField(GeneratedMessageV3.Builder<?> builder) {
     }
 
     private <T extends NodeInstanceContainer & ContextInstanceContainer & ContextableInstance> WorkflowContext buildWorkflowContext(T nodeInstance) {
-        List<NodeInstance> nodeInstances = new ArrayList<>(nodeInstance.getNodeInstances());
+        List<NodeInstance> nodeInstances = new ArrayList<>(nodeInstance.getSerializableNodeInstances());
         List<ContextInstance> exclusiveGroupInstances = nodeInstance.getContextInstances(ExclusiveGroup.EXCLUSIVE_GROUP);
         VariableScopeInstance variableScopeInstance = (VariableScopeInstance) nodeInstance.getContextInstance(VariableScope.VARIABLE_SCOPE);
         List<Map.Entry<String, Object>> variables = (variableScopeInstance != null) ? new ArrayList<>(variableScopeInstance.getVariables().entrySet()) : Collections.emptyList();