Java tutorial
/* * Druid - a distributed column store. * Copyright (C) 2012 Metamarkets Group Inc. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ package com.metamx.druid.query.timeseries; import com.google.common.base.Function; import com.google.common.base.Joiner; import com.google.common.collect.Lists; import com.google.common.collect.Maps; import com.google.common.collect.Ordering; import com.metamx.common.guava.MergeSequence; import com.metamx.common.guava.Sequence; import com.metamx.common.guava.nary.BinaryFn; import com.metamx.druid.Query; import com.metamx.druid.QueryGranularity; import com.metamx.druid.ResultGranularTimestampComparator; import com.metamx.druid.TimeseriesBinaryFn; import com.metamx.druid.aggregation.AggregatorFactory; import com.metamx.druid.aggregation.post.PostAggregator; import com.metamx.druid.collect.OrderedMergeSequence; import com.metamx.druid.query.CacheStrategy; import com.metamx.druid.query.IntervalChunkingQueryRunner; import com.metamx.druid.query.MetricManipulationFn; import com.metamx.druid.query.QueryCacheHelper; import com.metamx.druid.query.QueryRunner; import com.metamx.druid.query.QueryToolChest; import com.metamx.druid.query.ResultMergeQueryRunner; import com.metamx.druid.query.filter.DimFilter; import com.metamx.druid.result.Result; import com.metamx.druid.result.TimeseriesResultValue; import com.metamx.emitter.service.ServiceMetricEvent; import org.codehaus.jackson.type.TypeReference; import org.joda.time.DateTime; import org.joda.time.Interval; import org.joda.time.Minutes; import org.joda.time.Period; import org.joda.time.format.ISODateTimeFormat; import javax.annotation.Nullable; import java.nio.ByteBuffer; import java.util.Iterator; import java.util.List; import java.util.Map; /** */ public class TimeseriesQueryQueryToolChest implements QueryToolChest<Result<TimeseriesResultValue>, TimeseriesQuery> { private static final byte TIMESERIES_QUERY = 0x0; private static final Joiner COMMA_JOIN = Joiner.on(","); private static final TypeReference<Result<TimeseriesResultValue>> TYPE_REFERENCE = new TypeReference<Result<TimeseriesResultValue>>() { }; private static final TypeReference<Object> OBJECT_TYPE_REFERENCE = new TypeReference<Object>() { }; @Override public QueryRunner<Result<TimeseriesResultValue>> mergeResults( QueryRunner<Result<TimeseriesResultValue>> queryRunner) { return new ResultMergeQueryRunner<Result<TimeseriesResultValue>>(queryRunner) { @Override protected Ordering<Result<TimeseriesResultValue>> makeOrdering( Query<Result<TimeseriesResultValue>> query) { return Ordering.from(new ResultGranularTimestampComparator<TimeseriesResultValue>( ((TimeseriesQuery) query).getGranularity())); } @Override protected BinaryFn<Result<TimeseriesResultValue>, Result<TimeseriesResultValue>, Result<TimeseriesResultValue>> createMergeFn( Query<Result<TimeseriesResultValue>> input) { TimeseriesQuery query = (TimeseriesQuery) input; return new TimeseriesBinaryFn(query.getGranularity(), query.getAggregatorSpecs(), query.getPostAggregatorSpecs()); } }; } @Override public Sequence<Result<TimeseriesResultValue>> mergeSequences( Sequence<Sequence<Result<TimeseriesResultValue>>> seqOfSequences) { return new OrderedMergeSequence<Result<TimeseriesResultValue>>(getOrdering(), seqOfSequences); } @Override public ServiceMetricEvent.Builder makeMetricBuilder(TimeseriesQuery query) { int numMinutes = 0; for (Interval interval : query.getIntervals()) { numMinutes += Minutes.minutesIn(interval).getMinutes(); } return new ServiceMetricEvent.Builder().setUser2(query.getDataSource()).setUser4("timeseries") .setUser5(COMMA_JOIN.join(query.getIntervals())).setUser6(String.valueOf(query.hasFilters())) .setUser7(String.format("%,d aggs", query.getAggregatorSpecs().size())) .setUser9(Minutes.minutes(numMinutes).toString()); } @Override public Function<Result<TimeseriesResultValue>, Result<TimeseriesResultValue>> makeMetricManipulatorFn( final TimeseriesQuery query, final MetricManipulationFn fn) { return new Function<Result<TimeseriesResultValue>, Result<TimeseriesResultValue>>() { @Override public Result<TimeseriesResultValue> apply(Result<TimeseriesResultValue> result) { final Map<String, Object> values = Maps.newHashMap(); final TimeseriesResultValue holder = result.getValue(); for (AggregatorFactory agg : query.getAggregatorSpecs()) { values.put(agg.getName(), fn.manipulate(agg, holder.getMetric(agg.getName()))); } for (PostAggregator postAgg : query.getPostAggregatorSpecs()) { values.put(postAgg.getName(), holder.getMetric(postAgg.getName())); } return new Result<TimeseriesResultValue>(result.getTimestamp(), new TimeseriesResultValue(values)); } }; } @Override public TypeReference<Result<TimeseriesResultValue>> getResultTypeReference() { return TYPE_REFERENCE; } @Override public CacheStrategy<Result<TimeseriesResultValue>, Object, TimeseriesQuery> getCacheStrategy( final TimeseriesQuery query) { return new CacheStrategy<Result<TimeseriesResultValue>, Object, TimeseriesQuery>() { private final List<AggregatorFactory> aggs = query.getAggregatorSpecs(); private final List<PostAggregator> postAggs = query.getPostAggregatorSpecs(); @Override public byte[] computeCacheKey(TimeseriesQuery query) { final DimFilter dimFilter = query.getDimensionsFilter(); final byte[] filterBytes = dimFilter == null ? new byte[] {} : dimFilter.getCacheKey(); final byte[] aggregatorBytes = QueryCacheHelper.computeAggregatorBytes(query.getAggregatorSpecs()); final byte[] granularityBytes = query.getGranularity().cacheKey(); return ByteBuffer .allocate(1 + granularityBytes.length + filterBytes.length + aggregatorBytes.length) .put(TIMESERIES_QUERY).put(granularityBytes).put(filterBytes).put(aggregatorBytes).array(); } @Override public TypeReference<Object> getCacheObjectClazz() { return OBJECT_TYPE_REFERENCE; } @Override public Function<Result<TimeseriesResultValue>, Object> prepareForCache() { return new Function<Result<TimeseriesResultValue>, Object>() { @Override public Object apply(@Nullable final Result<TimeseriesResultValue> input) { TimeseriesResultValue results = input.getValue(); final List<Object> retVal = Lists.newArrayListWithCapacity(1 + aggs.size()); retVal.add(input.getTimestamp().getMillis()); for (AggregatorFactory agg : aggs) { retVal.add(results.getMetric(agg.getName())); } return retVal; } }; } @Override public Function<Object, Result<TimeseriesResultValue>> pullFromCache() { return new Function<Object, Result<TimeseriesResultValue>>() { private final QueryGranularity granularity = query.getGranularity(); @Override public Result<TimeseriesResultValue> apply(@Nullable Object input) { List<Object> results = (List<Object>) input; Map<String, Object> retVal = Maps.newLinkedHashMap(); Iterator<AggregatorFactory> aggsIter = aggs.iterator(); Iterator<Object> resultIter = results.iterator(); DateTime timestamp = granularity.toDateTime(((Number) resultIter.next()).longValue()); while (aggsIter.hasNext() && resultIter.hasNext()) { final AggregatorFactory factory = aggsIter.next(); retVal.put(factory.getName(), factory.deserialize(resultIter.next())); } for (PostAggregator postAgg : postAggs) { retVal.put(postAgg.getName(), postAgg.compute(retVal)); } return new Result<TimeseriesResultValue>(timestamp, new TimeseriesResultValue(retVal)); } }; } @Override public Sequence<Result<TimeseriesResultValue>> mergeSequences( Sequence<Sequence<Result<TimeseriesResultValue>>> seqOfSequences) { return new MergeSequence<Result<TimeseriesResultValue>>(getOrdering(), seqOfSequences); } }; } @Override public QueryRunner<Result<TimeseriesResultValue>> preMergeQueryDecoration( QueryRunner<Result<TimeseriesResultValue>> runner) { return new IntervalChunkingQueryRunner<Result<TimeseriesResultValue>>(runner, Period.months(1)); } @Override public QueryRunner<Result<TimeseriesResultValue>> postMergeQueryDecoration( QueryRunner<Result<TimeseriesResultValue>> runner) { return runner; } public Ordering<Result<TimeseriesResultValue>> getOrdering() { return Ordering.natural(); } }