org.elasticsearch.search.aggregations.InternalAggregation Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of elasticsearch Show documentation
Show all versions of elasticsearch Show documentation
Elasticsearch subproject :server
/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.search.aggregations;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.io.stream.NamedWriteable;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.util.BigArray;
import org.elasticsearch.common.util.BigArrays;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.rest.action.search.RestSearchAction;
import org.elasticsearch.script.ScriptService;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
import org.elasticsearch.search.aggregations.support.AggregationPath;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.function.IntConsumer;
/**
* An internal implementation of {@link Aggregation}. Serves as a base class for all aggregation implementations.
*/
public abstract class InternalAggregation implements Aggregation, NamedWriteable {
public static class ReduceContext {
private final BigArrays bigArrays;
private final ScriptService scriptService;
private final IntConsumer multiBucketConsumer;
private final boolean isFinalReduce;
public ReduceContext(BigArrays bigArrays, ScriptService scriptService, boolean isFinalReduce) {
this(bigArrays, scriptService, (s) -> {}, isFinalReduce);
}
public ReduceContext(BigArrays bigArrays, ScriptService scriptService, IntConsumer multiBucketConsumer, boolean isFinalReduce) {
this.bigArrays = bigArrays;
this.scriptService = scriptService;
this.multiBucketConsumer = multiBucketConsumer;
this.isFinalReduce = isFinalReduce;
}
/**
* Returns true iff the current reduce phase is the final reduce phase. This indicates if operations like
* pipeline aggregations should be applied or if specific features like minDocCount should be taken into account.
* Operations that are potentially loosing information can only be applied during the final reduce phase.
*/
public boolean isFinalReduce() {
return isFinalReduce;
}
public BigArrays bigArrays() {
return bigArrays;
}
public ScriptService scriptService() {
return scriptService;
}
/**
* Adds count buckets to the global count for the request and fails if this number is greater than
* the maximum number of buckets allowed in a response
*/
public void consumeBucketsAndMaybeBreak(int size) {
multiBucketConsumer.accept(size);
}
}
protected final String name;
protected final Map metaData;
private final List pipelineAggregators;
/**
* Constructs an get with a given name.
*
* @param name The name of the get.
*/
protected InternalAggregation(String name, List pipelineAggregators, Map metaData) {
this.name = name;
this.pipelineAggregators = pipelineAggregators;
this.metaData = metaData;
}
/**
* Read from a stream.
*/
protected InternalAggregation(StreamInput in) throws IOException {
name = in.readString();
metaData = in.readMap();
pipelineAggregators = in.readNamedWriteableList(PipelineAggregator.class);
}
@Override
public final void writeTo(StreamOutput out) throws IOException {
out.writeString(name);
out.writeGenericValue(metaData);
out.writeNamedWriteableList(pipelineAggregators);
doWriteTo(out);
}
protected abstract void doWriteTo(StreamOutput out) throws IOException;
@Override
public String getName() {
return name;
}
/**
* Reduces the given aggregations to a single one and returns it. In most cases, the assumption will be the all given
* aggregations are of the same type (the same type as this aggregation). For best efficiency, when implementing,
* try reusing an existing instance (typically the first in the given list) to save on redundant object
* construction.
*/
public final InternalAggregation reduce(List aggregations, ReduceContext reduceContext) {
InternalAggregation aggResult = doReduce(aggregations, reduceContext);
if (reduceContext.isFinalReduce()) {
for (PipelineAggregator pipelineAggregator : pipelineAggregators) {
aggResult = pipelineAggregator.reduce(aggResult, reduceContext);
}
}
return aggResult;
}
public abstract InternalAggregation doReduce(List aggregations, ReduceContext reduceContext);
/**
* Get the value of specified path in the aggregation.
*
* @param path
* the path to the property in the aggregation tree
* @return the value of the property
*/
public Object getProperty(String path) {
AggregationPath aggPath = AggregationPath.parse(path);
return getProperty(aggPath.getPathElementsAsStringList());
}
public abstract Object getProperty(List path);
/**
* Read a size under the assumption that a value of 0 means unlimited.
*/
protected static int readSize(StreamInput in) throws IOException {
final int size = in.readVInt();
return size == 0 ? Integer.MAX_VALUE : size;
}
/**
* Write a size under the assumption that a value of 0 means unlimited.
*/
protected static void writeSize(int size, StreamOutput out) throws IOException {
if (size == Integer.MAX_VALUE) {
size = 0;
}
out.writeVInt(size);
}
@Override
public Map getMetaData() {
return metaData;
}
public List pipelineAggregators() {
return pipelineAggregators;
}
@Override
public String getType() {
return getWriteableName();
}
@Override
public final XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
if (params.paramAsBoolean(RestSearchAction.TYPED_KEYS_PARAM, false)) {
// Concatenates the type and the name of the aggregation (ex: top_hits#foo)
builder.startObject(String.join(TYPED_KEYS_DELIMITER, getType(), getName()));
} else {
builder.startObject(getName());
}
if (this.metaData != null) {
builder.field(CommonFields.META.getPreferredName());
builder.map(this.metaData);
}
doXContentBody(builder, params);
builder.endObject();
return builder;
}
public abstract XContentBuilder doXContentBody(XContentBuilder builder, Params params) throws IOException;
@Override
public int hashCode() {
return Objects.hash(name, metaData, pipelineAggregators, doHashCode());
}
/**
* Opportunity for subclasses to the {@link #hashCode()} for this
* class.
**/
protected abstract int doHashCode();
@Override
public boolean equals(Object obj) {
if (obj == null) {
return false;
}
if (obj.getClass() != getClass()) {
return false;
}
InternalAggregation other = (InternalAggregation) obj;
return Objects.equals(name, other.name) &&
Objects.equals(pipelineAggregators, other.pipelineAggregators) &&
Objects.equals(metaData, other.metaData) &&
doEquals(obj);
}
/**
* Opportunity for subclasses to add criteria to the {@link #equals(Object)}
* method for this class.
*
* This method can safely cast obj to the subclass since the
* {@link #equals(Object)} method checks that obj is the same
* class as this
*/
protected abstract boolean doEquals(Object obj);
@Override
public String toString() {
return Strings.toString(this);
}
}