NIFI-15670 - Flow import/export with stateful components state

src/main/java/org/apache/nifi/flow/VersionedComponentState.java

@@ -0,0 +1,72 @@
+/*
+ * 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.apache.nifi.flow;
+
+import io.swagger.v3.oas.annotations.media.Schema;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Objects;
+
+public class VersionedComponentState {
+
+    private Map<String, String> clusterState;
+    private List<Map<String, String>> localNodeStates;
+
+    @Schema(description = "The cluster-scoped state of the component, or null if not exported")
+    public Map<String, String> getClusterState() {
+        return clusterState;
+    }
+
+    public void setClusterState(final Map<String, String> clusterState) {
+        this.clusterState = clusterState;
+    }
+
+    @Schema(description = "The local-scoped state of the component ordered by node ordinal index, or null if not exported")
+    public List<Map<String, String>> getLocalNodeStates() {
+        return localNodeStates;
+    }
+
+    public void setLocalNodeStates(final List<Map<String, String>> localNodeStates) {
+        this.localNodeStates = localNodeStates;
+    }
+
+    @Override
+    public boolean equals(final Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+        final VersionedComponentState that = (VersionedComponentState) o;
+        return Objects.equals(clusterState, that.clusterState) && Objects.equals(localNodeStates, that.localNodeStates);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(clusterState, localNodeStates);
+    }
+
+    @Override
+    public String toString() {
+        return "VersionedComponentState[clusterState=%s, localNodeStates=%s]".formatted(
+                clusterState != null ? clusterState.size() + " entries" : "null",
+                localNodeStates != null ? localNodeStates.size() + " nodes" : "null");
+    }
+}

src/main/java/org/apache/nifi/flow/VersionedConfigurableExtension.java

@@ -28,6 +28,7 @@ public abstract class VersionedConfigurableExtension extends VersionedComponent
 
     private Map<String, String> properties;
     private Map<String, VersionedPropertyDescriptor> propertyDescriptors;
+    private VersionedComponentState componentState;
 
     @Override
     @Schema(description = "The type of the extension component")
@@ -74,4 +75,13 @@ public void setPropertyDescriptors(Map<String, VersionedPropertyDescriptor> prop
         this.propertyDescriptors = propertyDescriptors;
     }
 
+    @Schema(description = "The state of the component, if exported with state")
+    public VersionedComponentState getComponentState() {
+        return componentState;
+    }
+
+    public void setComponentState(final VersionedComponentState componentState) {
+        this.componentState = componentState;
+    }
+
 }