[Rest Api Compatibility] MovAvgPipelineAggregation (#82828)

rest-api-spec/src/yamlRestTestV7Compat/resources/rest-api-spec/test/search.aggregation/10_moving_avg.yml

@@ -0,0 +1,30 @@
+---
+setup:
+  - skip:
+      version: "9.0.0 - "
+      reason: "compatible from 8.x to 7.x"
+      features:
+        - "headers"
+
+---
+moving_avg agg throws exception:
+  - do:
+      catch: "/Moving Average aggregation usage is not supported. Use the \\[moving_fn\\] aggregation instead./"
+      search:
+        rest_total_hits_as_int: true
+        body:
+          aggs:
+            the_histo:
+              date_histogram:
+                field: "date"
+                calendar_interval: "1d"
+              aggs:
+                the_avg:
+                  avg:
+                    field: "value_field"
+                the_movavg:
+                  moving_avg:
+                    buckets_path: "the_avg"
+      headers:
+        Content-Type: "application/vnd.elasticsearch+json;compatible-with=7"
+        Accept: "application/vnd.elasticsearch+json;compatible-with=7"

server/src/main/java/org/elasticsearch/search/SearchModule.java

@@ -201,6 +201,7 @@
 import org.elasticsearch.search.aggregations.pipeline.InternalStatsBucket;
 import org.elasticsearch.search.aggregations.pipeline.MaxBucketPipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.MinBucketPipelineAggregationBuilder;
+import org.elasticsearch.search.aggregations.pipeline.MovAvgPipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.MovFnPipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.PercentilesBucketPipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.SerialDiffPipelineAggregationBuilder;
@@ -783,6 +784,15 @@ private void registerPipelineAggregations(List<SearchPlugin> plugins) {
                 MovFnPipelineAggregationBuilder.PARSER
             )
         );
+        if (RestApiVersion.minimumSupported() == RestApiVersion.V_7) {
+            registerPipelineAggregation(
+                new PipelineAggregationSpec(
+                    MovAvgPipelineAggregationBuilder.NAME_V7,
+                    MovAvgPipelineAggregationBuilder::new,
+                    MovAvgPipelineAggregationBuilder.PARSER
+                )
+            );
+        }
 
         registerFromPlugin(plugins, SearchPlugin::getPipelineAggregations, this::registerPipelineAggregation);
     }

server/src/main/java/org/elasticsearch/search/aggregations/pipeline/MovAvgPipelineAggregationBuilder.java

@@ -0,0 +1,75 @@
+/*
+ * 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.search.aggregations.pipeline;
+
+import org.elasticsearch.common.ParsingException;
+import org.elasticsearch.common.io.stream.StreamInput;
+import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.common.logging.DeprecationLogger;
+import org.elasticsearch.core.RestApiVersion;
+import org.elasticsearch.index.query.CommonTermsQueryBuilder;
+import org.elasticsearch.xcontent.ContextParser;
+import org.elasticsearch.xcontent.ParseField;
+import org.elasticsearch.xcontent.XContentBuilder;
+
+import java.io.IOException;
+import java.util.Map;
+
+/**
+ * The actual moving_avg aggregation was removed as a breaking change in 8.0. This class exists to provide a friendlier error message
+ * if somebody attempts to use the moving_avg aggregation via the compatible-with=7 mechanism.
+ *
+ * We can remove this class entirely when v7 rest api compatibility is dropped.
+ *
+ * @deprecated Only for 7.x rest compat
+ */
+@Deprecated
+public class MovAvgPipelineAggregationBuilder extends AbstractPipelineAggregationBuilder<MovAvgPipelineAggregationBuilder> {
+    private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(CommonTermsQueryBuilder.class);
+    public static final String MOVING_AVG_AGG_DEPRECATION_MSG = "Moving Average aggregation usage is not supported. "
+        + "Use the [moving_fn] aggregation instead.";
+
+    public static ParseField NAME_V7 = new ParseField("moving_avg").withAllDeprecated(MOVING_AVG_AGG_DEPRECATION_MSG)
+        .forRestApiVersion(RestApiVersion.equalTo(RestApiVersion.V_7));
+
+    public static final ContextParser<String, MovAvgPipelineAggregationBuilder> PARSER = (parser, name) -> {
+        deprecationLogger.compatibleCritical("moving_avg_aggregation", MOVING_AVG_AGG_DEPRECATION_MSG);
+        throw new ParsingException(parser.getTokenLocation(), MOVING_AVG_AGG_DEPRECATION_MSG);
+    };
+
+    public MovAvgPipelineAggregationBuilder(StreamInput in) throws IOException {
+        super(in, NAME_V7.getPreferredName());
+        throw new UnsupportedOperationException("moving_avg is not meant to be used.");
+    }
+
+    @Override
+    protected void doWriteTo(StreamOutput out) throws IOException {
+        throw new UnsupportedOperationException("moving_avg is not meant to be used.");
+    }
+
+    @Override
+    protected PipelineAggregator createInternal(Map<String, Object> metadata) {
+        throw new UnsupportedOperationException("moving_avg is not meant to be used.");
+    }
+
+    @Override
+    protected XContentBuilder internalXContent(XContentBuilder builder, Params params) throws IOException {
+        throw new UnsupportedOperationException("moving_avg is not meant to be used.");
+    }
+
+    @Override
+    protected void validate(ValidationContext context) {
+        throw new UnsupportedOperationException("moving_avg is not meant to be used.");
+    }
+
+    @Override
+    public final String getWriteableName() {
+        return null;
+    }
+}

server/src/test/java/org/elasticsearch/search/SearchModuleTests.java

@@ -36,6 +36,7 @@
 import org.elasticsearch.search.aggregations.pipeline.AbstractPipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.DerivativePipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.InternalDerivative;
+import org.elasticsearch.search.aggregations.pipeline.MovAvgPipelineAggregationBuilder;
 import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
 import org.elasticsearch.search.aggregations.support.AggregationContext;
 import org.elasticsearch.search.aggregations.support.CoreValuesSourceType;
@@ -478,6 +479,8 @@ public CheckedBiConsumer<ShardSearchRequest, StreamOutput, IOException> getReque
     private static final String[] REST_COMPATIBLE_QUERIES = new String[] {
         TypeQueryV7Builder.NAME_V7.getPreferredName(),
         CommonTermsQueryBuilder.NAME_V7.getPreferredName() };
+    private static final String[] REST_COMPATIBLE_AGGREGATIONS = new String[] {
+        MovAvgPipelineAggregationBuilder.NAME_V7.getPreferredName() };
 
     /**
      * Dummy test {@link AggregationBuilder} used to test registering aggregation builders.
@@ -765,7 +768,7 @@ public List<SearchPlugin.QuerySpec<?>> getQueries() {
             .filter(e -> RestApiVersion.current().matches(e.restApiCompatibility))
             .collect(toSet()),
             // -1 because of the registered in the test
-            hasSize(searchModule.getNamedXContents().size() - REST_COMPATIBLE_QUERIES.length - 1)
+            hasSize(searchModule.getNamedXContents().size() - REST_COMPATIBLE_QUERIES.length - REST_COMPATIBLE_AGGREGATIONS.length - 1)
         );
 
         final List<NamedXContentRegistry.Entry> compatEntry = searchModule.getNamedXContents()