[7.x] Updating ingest pipeline without changes is no-op (#78196)

server/src/main/java/org/elasticsearch/action/ingest/PutPipelineTransportAction.java

@@ -25,8 +25,10 @@
 import org.elasticsearch.common.inject.Inject;
 import org.elasticsearch.common.xcontent.XContentHelper;
 import org.elasticsearch.ingest.IngestInfo;
+import org.elasticsearch.ingest.IngestMetadata;
 import org.elasticsearch.ingest.IngestService;
 import org.elasticsearch.ingest.Pipeline;
+import org.elasticsearch.ingest.PipelineConfiguration;
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.transport.TransportService;
 
@@ -57,22 +59,43 @@ public PutPipelineTransportAction(ThreadPool threadPool, TransportService transp
     @Override
     protected void masterOperation(PutPipelineRequest request, ClusterState state, ActionListener<AcknowledgedResponse> listener)
             throws Exception {
+
+        Map<String, Object> pipelineConfig = null;
+        IngestMetadata currentIngestMetadata = state.metadata().custom(IngestMetadata.TYPE);
+        if (currentIngestMetadata != null && currentIngestMetadata.getPipelines().containsKey(request.getId())) {
+            pipelineConfig = XContentHelper.convertToMap(request.getSource(), false, request.getXContentType()).v2();
+            PipelineConfiguration currentPipeline = currentIngestMetadata.getPipelines().get(request.getId());
+            if (currentPipeline.getConfigAsMap().equals(pipelineConfig)) {
+                // existing pipeline matches request pipeline -- no need to update
+                listener.onResponse(AcknowledgedResponse.TRUE);
+                return;
+            }
+        }
+
         if (state.getNodes().getMinNodeVersion().before(Version.V_7_15_0)) {
-            Map<String, Object> pipelineConfig = XContentHelper.convertToMap(request.getSource(), false, request.getXContentType()).v2();
+            pipelineConfig = pipelineConfig == null
+                ? XContentHelper.convertToMap(request.getSource(), false, request.getXContentType()).v2()
+                : pipelineConfig;
             if (pipelineConfig.containsKey(Pipeline.META_KEY)) {
                 throw new IllegalStateException("pipelines with _meta field require minimum node version of " + Version.V_7_15_0);
             }
         }
         NodesInfoRequest nodesInfoRequest = new NodesInfoRequest();
-        nodesInfoRequest.clear()
-            .addMetric(NodesInfoRequest.Metric.INGEST.metricName());
-        client.admin().cluster().nodesInfo(nodesInfoRequest, ActionListener.wrap(nodeInfos -> {
-            Map<DiscoveryNode, IngestInfo> ingestInfos = new HashMap<>();
-            for (NodeInfo nodeInfo : nodeInfos.getNodes()) {
-                ingestInfos.put(nodeInfo.getNode(), nodeInfo.getInfo(IngestInfo.class));
-            }
-            ingestService.putPipeline(ingestInfos, request, listener);
-        }, listener::onFailure));
+        nodesInfoRequest.clear();
+        nodesInfoRequest.addMetric(NodesInfoRequest.Metric.INGEST.metricName());
+        client.admin().cluster().nodesInfo(
+            nodesInfoRequest,
+            ActionListener.wrap(
+                nodeInfos -> {
+                    Map<DiscoveryNode, IngestInfo> ingestInfos = new HashMap<>();
+                    for (NodeInfo nodeInfo : nodeInfos.getNodes()) {
+                        ingestInfos.put(nodeInfo.getNode(), nodeInfo.getInfo(IngestInfo.class));
+                    }
+                    ingestService.putPipeline(ingestInfos, request, listener);
+                },
+                listener::onFailure
+            )
+        );
     }
 
     @Override

server/src/test/java/org/elasticsearch/action/ingest/PutPipelineTransportActionTests.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0 and the Server Side Public License, v 1; you may not use this file except
+ * in compliance with, at your election, the Elastic License 2.0 or the Server
+ * Side Public License, v 1.
+ */
+
+package org.elasticsearch.action.ingest;
+
+import org.elasticsearch.core.Tuple;
+import org.elasticsearch.test.ESTestCase;
+
+import static org.elasticsearch.core.Tuple.tuple;
+
+public class PutPipelineTransportActionTests extends ESTestCase {
+
+
+    private static Tuple<String, Object> randomMapEntry() {
+        return tuple(randomAlphaOfLength(5), randomObject());
+    }
+
+    private static Object randomObject() {
+        return randomFrom(
+            random(),
+            ESTestCase::randomLong,
+            () -> generateRandomStringArray(10, 5, true),
+            () -> randomMap(3, 5, PutPipelineTransportActionTests::randomMapEntry),
+            () -> randomAlphaOfLength(5),
+            ESTestCase::randomTimeValue,
+            ESTestCase::randomDouble
+        );
+    }
+}

test/framework/src/main/java/org/elasticsearch/test/ESTestCase.java

@@ -781,6 +781,14 @@ public static <T> T randomFrom(Random random, T... array) {
         return RandomPicks.randomFrom(random, array);
     }
 
+    /** Pick a random object from the given array of suppliers. The array must not be empty. */
+    @SafeVarargs
+    @SuppressWarnings("varargs")
+    public static <T> T randomFrom(Random random, Supplier<T>... array) {
+        Supplier<T> supplier = RandomPicks.randomFrom(random, array);
+        return supplier.get();
+    }
+
     /** Pick a random object from the given list. */
     public static <T> T randomFrom(List<T> list) {
         return RandomPicks.randomFrom(random(), list);

test/framework/src/main/java/org/elasticsearch/test/client/NoOpNodeClient.java

@@ -26,6 +26,7 @@
 
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicLong;
 import java.util.function.Supplier;
 
 /**
@@ -37,6 +38,8 @@
  */
 public class NoOpNodeClient extends NodeClient {
 
+    private final AtomicLong executionCount = new AtomicLong(0);
+
     /**
      * Build with {@link ThreadPool}. This {@linkplain ThreadPool} is terminated on {@link #close()}.
      */
@@ -54,6 +57,7 @@ public NoOpNodeClient(String testName) {
     @Override
     public <Request extends ActionRequest, Response extends ActionResponse>
     void doExecute(ActionType<Response> action, Request request, ActionListener<Response> listener) {
+        executionCount.incrementAndGet();
         listener.onResponse(null);
     }
 
@@ -70,13 +74,15 @@ public void initialize(
     @Override
     public <Request extends ActionRequest, Response extends ActionResponse>
     Task executeLocally(ActionType<Response> action, Request request, ActionListener<Response> listener) {
+        executionCount.incrementAndGet();
         listener.onResponse(null);
         return null;
     }
 
     @Override
     public <Request extends ActionRequest, Response extends ActionResponse>
     Task executeLocally(ActionType<Response> action, Request request, TaskListener<Response> listener) {
+        executionCount.incrementAndGet();
         listener.onResponse(null, null);
         return null;
     }
@@ -99,4 +105,8 @@ public void close() {
             throw new ElasticsearchException(e.getMessage(), e);
         }
     }
+
+    public long getExecutionCount() {
+        return executionCount.get();
+    }
 }