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* 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
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package org.elasticsearch.search.aggregations.pipeline.having;
import com.google.common.base.Function;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.script.CompiledScript;
import org.elasticsearch.script.ExecutableScript;
import org.elasticsearch.script.Script;
import org.elasticsearch.script.ScriptContext;
import org.elasticsearch.search.aggregations.Aggregation;
import org.elasticsearch.search.aggregations.InternalAggregation;
import org.elasticsearch.search.aggregations.InternalAggregation.ReduceContext;
import org.elasticsearch.search.aggregations.InternalAggregation.Type;
import org.elasticsearch.search.aggregations.InternalMultiBucketAggregation;
import org.elasticsearch.search.aggregations.bucket.MultiBucketsAggregation.Bucket;
import org.elasticsearch.search.aggregations.pipeline.BucketHelpers.GapPolicy;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregatorFactory;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregatorStreams;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import static org.elasticsearch.search.aggregations.pipeline.BucketHelpers.resolveBucketValue;
public class BucketSelectorPipelineAggregator extends PipelineAggregator {
public final static Type TYPE = new Type("bucket_selector");
public final static PipelineAggregatorStreams.Stream STREAM = new PipelineAggregatorStreams.Stream() {
@Override
public BucketSelectorPipelineAggregator readResult(StreamInput in) throws IOException {
BucketSelectorPipelineAggregator result = new BucketSelectorPipelineAggregator();
result.readFrom(in);
return result;
}
};
public static void registerStreams() {
PipelineAggregatorStreams.registerStream(STREAM, TYPE.stream());
}
private static final Function<Aggregation, InternalAggregation> FUNCTION = new Function<Aggregation, InternalAggregation>() {
@Override
public InternalAggregation apply(Aggregation input) {
return (InternalAggregation) input;
}
};
private GapPolicy gapPolicy;
private Script script;
private Map<String, String> bucketsPathsMap;
public BucketSelectorPipelineAggregator() {
}
public BucketSelectorPipelineAggregator(String name, Map<String, String> bucketsPathsMap, Script script, GapPolicy gapPolicy,
Map<String, Object> metadata) {
super(name, bucketsPathsMap.values().toArray(new String[bucketsPathsMap.size()]), metadata);
this.bucketsPathsMap = bucketsPathsMap;
this.script = script;
this.gapPolicy = gapPolicy;
}
@Override
public Type type() {
return TYPE;
}
@Override
public InternalAggregation reduce(InternalAggregation aggregation, ReduceContext reduceContext) {
InternalMultiBucketAggregation<InternalMultiBucketAggregation, InternalMultiBucketAggregation.InternalBucket> originalAgg = (InternalMultiBucketAggregation<InternalMultiBucketAggregation, InternalMultiBucketAggregation.InternalBucket>) aggregation;
List<? extends Bucket> buckets = originalAgg.getBuckets();
CompiledScript compiledScript = reduceContext.scriptService().compile(script, ScriptContext.Standard.AGGS, reduceContext, Collections.<String, String>emptyMap());
List newBuckets = new ArrayList<>();
for (Bucket bucket : buckets) {
Map<String, Object> vars = new HashMap<>();
if (script.getParams() != null) {
vars.putAll(script.getParams());
}
for (Map.Entry<String, String> entry : bucketsPathsMap.entrySet()) {
String varName = entry.getKey();
String bucketsPath = entry.getValue();
Double value = resolveBucketValue(originalAgg, bucket, bucketsPath, gapPolicy);
vars.put(varName, value);
}
ExecutableScript executableScript = reduceContext.scriptService().executable(compiledScript, vars);
Object scriptReturnValue = executableScript.run();
final boolean keepBucket;
// TODO: WTF!!!!!
if ("expression".equals(script.getLang())) {
double scriptDoubleValue = (double) scriptReturnValue;
keepBucket = scriptDoubleValue == 1.0;
} else {
keepBucket = (boolean) scriptReturnValue;
}
if (keepBucket) {
newBuckets.add(bucket);
}
}
return originalAgg.create(newBuckets);
}
@Override
protected void doWriteTo(StreamOutput out) throws IOException {
script.writeTo(out);
gapPolicy.writeTo(out);
out.writeGenericValue(bucketsPathsMap);
}
@SuppressWarnings("unchecked")
@Override
protected void doReadFrom(StreamInput in) throws IOException {
script = Script.readScript(in);
gapPolicy = GapPolicy.readFrom(in);
bucketsPathsMap = (Map<String, String>) in.readGenericValue();
}
public static class Factory extends PipelineAggregatorFactory {
private Script script;
private GapPolicy gapPolicy;
private Map<String, String> bucketsPathsMap;
public Factory(String name, Map<String, String> bucketsPathsMap, Script script, GapPolicy gapPolicy) {
super(name, TYPE.name(), bucketsPathsMap.values().toArray(new String[bucketsPathsMap.size()]));
this.bucketsPathsMap = bucketsPathsMap;
this.script = script;
this.gapPolicy = gapPolicy;
}
@Override
protected PipelineAggregator createInternal(Map<String, Object> metaData) throws IOException {
return new BucketSelectorPipelineAggregator(name, bucketsPathsMap, script, gapPolicy, metaData);
}
}
}