Migrate sampler and missing aggregations to NamedWriteable

This is another step down the path to removing aggregation's special
"streams" which reimplement NamedWriteable.

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

@@ -551,13 +551,16 @@ public class SearchModule extends AbstractModule {
                 CardinalityAggregationBuilder.AGGREGATION_NAME_FIELD).addResultReader(InternalCardinality::new));
         registerAggregation(new AggregationSpec(GlobalAggregationBuilder::new, GlobalAggregationBuilder::parse,
                 GlobalAggregationBuilder.AGGREGATION_NAME_FIELD).addResultReader(InternalGlobal::new));
-        registerAggregation(MissingAggregationBuilder::new, new MissingParser(), MissingAggregationBuilder.AGGREGATION_NAME_FIELD);
+        registerAggregation(
+                new AggregationSpec(MissingAggregationBuilder::new, new MissingParser(), MissingAggregationBuilder.AGGREGATION_NAME_FIELD)
+                        .addResultReader(InternalMissing::new));
         registerAggregation(new AggregationSpec(FilterAggregationBuilder::new, FilterAggregationBuilder::parse,
                 FilterAggregationBuilder.AGGREGATION_NAME_FIELD).addResultReader(InternalFilter::new));
         registerAggregation(new AggregationSpec(FiltersAggregationBuilder::new, FiltersAggregationBuilder::parse,
                 FiltersAggregationBuilder.AGGREGATION_NAME_FIELD).addResultReader(InternalFilters::new));
-        registerAggregation(SamplerAggregationBuilder::new, SamplerAggregationBuilder::parse,
-                SamplerAggregationBuilder.AGGREGATION_NAME_FIELD);
+        registerAggregation(new AggregationSpec(SamplerAggregationBuilder::new, SamplerAggregationBuilder::parse,
+                SamplerAggregationBuilder.AGGREGATION_NAME_FIELD).addResultReader(InternalSampler.NAME, InternalSampler::new)
+                        .addResultReader(UnmappedSampler.NAME, UnmappedSampler::new));
         registerAggregation(DiversifiedAggregationBuilder::new, new DiversifiedSamplerParser(),
                 DiversifiedAggregationBuilder.AGGREGATION_NAME_FIELD);
         registerAggregation(TermsAggregationBuilder::new, new TermsParser(), TermsAggregationBuilder.AGGREGATION_NAME_FIELD);
@@ -767,9 +770,6 @@ public class SearchModule extends AbstractModule {
 
     static {
         // buckets
-        InternalSampler.registerStreams();
-        UnmappedSampler.registerStreams();
-        InternalMissing.registerStreams();
         StringTerms.registerStreams();
         LongTerms.registerStreams();
         SignificantStringTerms.registerStreams();

core/src/main/java/org/elasticsearch/search/aggregations/bucket/missing/InternalMissing.java

@@ -19,7 +19,6 @@
 package org.elasticsearch.search.aggregations.bucket.missing;
 
 import org.elasticsearch.common.io.stream.StreamInput;
-import org.elasticsearch.search.aggregations.AggregationStreams;
 import org.elasticsearch.search.aggregations.InternalAggregations;
 import org.elasticsearch.search.aggregations.bucket.InternalSingleBucketAggregation;
 import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
@@ -28,37 +27,21 @@ import java.io.IOException;
 import java.util.List;
 import java.util.Map;
 
-/**
- *
- */
 public class InternalMissing extends InternalSingleBucketAggregation implements Missing {
-
-    public static final Type TYPE = new Type("missing");
-
-    public static final AggregationStreams.Stream STREAM = new AggregationStreams.Stream() {
-        @Override
-        public InternalMissing readResult(StreamInput in) throws IOException {
-            InternalMissing missing = new InternalMissing();
-            missing.readFrom(in);
-            return missing;
-        }
-    };
-
-    public static void registerStreams() {
-        AggregationStreams.registerStream(STREAM, TYPE.stream());
-    }
-
-
-    InternalMissing() {
-    }
-
     InternalMissing(String name, long docCount, InternalAggregations aggregations, List<PipelineAggregator> pipelineAggregators, Map<String, Object> metaData) {
         super(name, docCount, aggregations, pipelineAggregators, metaData);
     }
 
+    /**
+     * Read from a stream.
+     */
+    public InternalMissing(StreamInput in) throws IOException {
+        super(in);
+    }
+
     @Override
-    public Type type() {
-        return TYPE;
+    public String getWriteableName() {
+        return MissingAggregationBuilder.NAME;
     }
 
     @Override

core/src/main/java/org/elasticsearch/search/aggregations/bucket/missing/MissingAggregationBuilder.java

@@ -24,6 +24,7 @@ import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
 import org.elasticsearch.common.xcontent.XContentBuilder;
 import org.elasticsearch.search.aggregations.AggregatorFactories.Builder;
+import org.elasticsearch.search.aggregations.InternalAggregation.Type;
 import org.elasticsearch.search.aggregations.AggregatorFactory;
 import org.elasticsearch.search.aggregations.support.AggregationContext;
 import org.elasticsearch.search.aggregations.support.ValueType;
@@ -36,18 +37,19 @@ import org.elasticsearch.search.aggregations.support.ValuesSourceType;
 import java.io.IOException;
 
 public class MissingAggregationBuilder extends ValuesSourceAggregationBuilder<ValuesSource, MissingAggregationBuilder> {
-    public static final String NAME = InternalMissing.TYPE.name();
+    public static final String NAME = "missing";
+    public static final Type TYPE = new Type(NAME);
     public static final ParseField AGGREGATION_NAME_FIELD = new ParseField(NAME);
 
     public MissingAggregationBuilder(String name, ValueType targetValueType) {
-        super(name, InternalMissing.TYPE, ValuesSourceType.ANY, targetValueType);
+        super(name, TYPE, ValuesSourceType.ANY, targetValueType);
     }
 
     /**
      * Read from a stream.
      */
     public MissingAggregationBuilder(StreamInput in) throws IOException {
-        super(in, InternalMissing.TYPE, ValuesSourceType.ANY);
+        super(in, TYPE, ValuesSourceType.ANY);
     }
 
     @Override

core/src/main/java/org/elasticsearch/search/aggregations/bucket/sampler/InternalSampler.java

@@ -19,7 +19,6 @@
 package org.elasticsearch.search.aggregations.bucket.sampler;
 
 import org.elasticsearch.common.io.stream.StreamInput;
-import org.elasticsearch.search.aggregations.AggregationStreams;
 import org.elasticsearch.search.aggregations.InternalAggregations;
 import org.elasticsearch.search.aggregations.bucket.InternalSingleBucketAggregation;
 import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
@@ -28,36 +27,22 @@ import java.io.IOException;
 import java.util.List;
 import java.util.Map;
 
-/**
-*
-*/
 public class InternalSampler extends InternalSingleBucketAggregation implements Sampler {
-
-    public static final Type TYPE = new Type("sampler");
-
-    public static final AggregationStreams.Stream STREAM = new AggregationStreams.Stream() {
-        @Override
-        public InternalSampler readResult(StreamInput in) throws IOException {
-            InternalSampler result = new InternalSampler();
-            result.readFrom(in);
-            return result;
-        }
-    };
-
-    public static void registerStreams() {
-        AggregationStreams.registerStream(STREAM, TYPE.stream());
-    }
-
-    InternalSampler() {
-    } // for serialization
-
+    public static final String NAME = "mapped_sampler";
     InternalSampler(String name, long docCount, InternalAggregations subAggregations, List<PipelineAggregator> pipelineAggregators, Map<String, Object> metaData) {
         super(name, docCount, subAggregations, pipelineAggregators, metaData);
     }
 
+    /**
+     * Read from a stream.
+     */
+    public InternalSampler(StreamInput in) throws IOException {
+        super(in);
+    }
+
     @Override
-    public Type type() {
-        return TYPE;
+    public String getWriteableName() {
+        return NAME;
     }
 
     @Override

core/src/main/java/org/elasticsearch/search/aggregations/bucket/sampler/SamplerAggregationBuilder.java

@@ -29,13 +29,15 @@ import org.elasticsearch.index.query.QueryParseContext;
 import org.elasticsearch.search.aggregations.AbstractAggregationBuilder;
 import org.elasticsearch.search.aggregations.AggregatorFactories.Builder;
 import org.elasticsearch.search.aggregations.AggregatorFactory;
+import org.elasticsearch.search.aggregations.InternalAggregation.Type;
 import org.elasticsearch.search.aggregations.support.AggregationContext;
 
 import java.io.IOException;
 import java.util.Objects;
 
 public class SamplerAggregationBuilder extends AbstractAggregationBuilder<SamplerAggregationBuilder> {
-    public static final String NAME = InternalSampler.TYPE.name();
+    public static final String NAME = "sampler";
+    private static final Type TYPE = new Type(NAME);
     public static final ParseField AGGREGATION_NAME_FIELD = new ParseField(NAME);
 
     public static final int DEFAULT_SHARD_SAMPLE_SIZE = 100;
@@ -43,14 +45,14 @@ public class SamplerAggregationBuilder extends AbstractAggregationBuilder<Sample
     private int shardSize = DEFAULT_SHARD_SAMPLE_SIZE;
 
     public SamplerAggregationBuilder(String name) {
-        super(name, InternalSampler.TYPE);
+        super(name, TYPE);
     }
 
     /**
      * Read from a stream.
      */
     public SamplerAggregationBuilder(StreamInput in) throws IOException {
-        super(in, InternalSampler.TYPE);
+        super(in, TYPE);
         shardSize = in.readVInt();
     }
 

core/src/main/java/org/elasticsearch/search/aggregations/bucket/sampler/UnmappedSampler.java

@@ -20,7 +20,6 @@ package org.elasticsearch.search.aggregations.bucket.sampler;
 
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.xcontent.XContentBuilder;
-import org.elasticsearch.search.aggregations.AggregationStreams;
 import org.elasticsearch.search.aggregations.InternalAggregation;
 import org.elasticsearch.search.aggregations.InternalAggregations;
 import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
@@ -29,37 +28,23 @@ import java.io.IOException;
 import java.util.List;
 import java.util.Map;
 
-/**
- *
- */
 public class UnmappedSampler extends InternalSampler {
-
-    public static final Type TYPE = new Type("sampler", "umsampler");
-
-
-    public static final AggregationStreams.Stream STREAM = new AggregationStreams.Stream() {
-        @Override
-        public UnmappedSampler readResult(StreamInput in) throws IOException {
-            UnmappedSampler sampler = new UnmappedSampler();
-            sampler.readFrom(in);
-            return sampler;
-        }
-    };
-
-    public static void registerStreams() {
-        AggregationStreams.registerStream(STREAM, TYPE.stream());
-    }
-
-    UnmappedSampler() {
-    }
+    public static final String NAME = "unmapped_sampler";
 
     public UnmappedSampler(String name, List<PipelineAggregator> pipelineAggregators, Map<String, Object> metaData) {
         super(name, 0, InternalAggregations.EMPTY, pipelineAggregators, metaData);
     }
 
+    /**
+     * Read from a stream.
+     */
+    public UnmappedSampler(StreamInput in) throws IOException {
+        super(in);
+    }
+
     @Override
-    public Type type() {
-        return TYPE;
+    public String getWriteableName() {
+        return NAME;
     }
 
     @Override

core/src/test/java/org/elasticsearch/search/aggregations/bucket/MissingIT.java

@@ -40,9 +40,6 @@ import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.core.IsNull.notNullValue;
 
-/**
- *
- */
 @ESIntegTestCase.SuiteScopeTestCase
 public class MissingIT extends ESIntegTestCase {