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ASF GitHub Bot commented on APEXMALHAR-1701: -------------------------------------------- Github user bhupeshchawda commented on a diff in the pull request: https://github.com/apache/apex-malhar/pull/335#discussion_r73160693 --- Diff: library/src/main/java/org/apache/apex/malhar/lib/dedup/AbstractDeduper.java --- @@ -0,0 +1,459 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF 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.apache.apex.malhar.lib.dedup; + +import java.util.Iterator; +import java.util.Map; +import java.util.Map.Entry; +import java.util.concurrent.ExecutionException; +import java.util.concurrent.Future; + +import javax.validation.constraints.NotNull; + +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import org.apache.apex.malhar.lib.state.BucketedState; +import org.apache.apex.malhar.lib.state.managed.ManagedTimeUnifiedStateImpl; +import org.apache.apex.malhar.lib.state.managed.TimeBucketAssigner; +import org.apache.hadoop.classification.InterfaceStability.Evolving; + +import com.google.common.base.Preconditions; +import com.google.common.collect.Maps; +import com.google.common.util.concurrent.Futures; + +import com.datatorrent.api.AutoMetric; +import com.datatorrent.api.Context; +import com.datatorrent.api.Context.OperatorContext; +import com.datatorrent.api.DAG; +import com.datatorrent.api.DefaultInputPort; +import com.datatorrent.api.DefaultOutputPort; +import com.datatorrent.api.Operator; +import com.datatorrent.api.Operator.ActivationListener; +import com.datatorrent.api.annotation.OperatorAnnotation; +import com.datatorrent.lib.fileaccess.FileAccessFSImpl; +import com.datatorrent.lib.fileaccess.TFileImpl; +import com.datatorrent.netlet.util.Slice; + +/** + * Abstract class which allows de-duplicating incoming tuples based on a configured key. + * Also supports expiry mechanism based on a configurable expiry period configured using {@link TimeBucketAssigner} + * in {@link ManagedTimeUnifiedStateImpl} + * Following steps are used in identifying the state of a particular tuple: + * 1. Check if the time of the tuple falls in an expired bucket. If so, the tuple is expired + * 2. If the tuple is a valid event, it is checked in the store whether the same key already exists in the + * time bucket identified by the event time. If, so, the tuple is a duplicate. + * 3. Otherwise the tuple is a unique tuple. + * + * @param <T> type of events + */ +@Evolving +@OperatorAnnotation(checkpointableWithinAppWindow = false) +public abstract class AbstractDeduper<T> + implements Operator, Operator.IdleTimeHandler, ActivationListener<Context>, Operator.CheckpointNotificationListener +{ + /** + * The input port on which events are received. + */ + public final transient DefaultInputPort<T> input = new DefaultInputPort<T>() + { + @Override + public final void process(T tuple) + { + processTuple(tuple); + } + }; + + /** + * The output port on which deduped events are emitted. + */ + public final transient DefaultOutputPort<T> unique = new DefaultOutputPort<>(); + + /** + * The output port on which duplicate events are emitted. + */ + public final transient DefaultOutputPort<T> duplicate = new DefaultOutputPort<>(); + + /** + * The output port on which expired events are emitted. + */ + public final transient DefaultOutputPort<T> expired = new DefaultOutputPort<>(); + + /** + * Whether or not the order of tuples be maintained. + * Making this "true" might entail some cost in performance, but makes the operator idempotent. + */ + private boolean preserveTupleOrder = true; + + @NotNull + protected final ManagedTimeUnifiedStateImpl managedState = new ManagedTimeUnifiedStateImpl(); + + /** + * Map to hold the result of a tuple processing (unique, duplicate, expired or error) until previous + * tuples get processed. This is used only when {@link #preserveTupleOrder} is true. + */ + private transient Map<T, Decision> decisions; + private transient long sleepMillis; + private transient Map<T, Future<Slice>> waitingEvents = Maps.newLinkedHashMap(); + private transient Map<Slice, Long> asyncEvents = Maps.newLinkedHashMap(); + + // Metrics + @AutoMetric + private transient long uniqueEvents; + @AutoMetric + private transient long duplicateEvents; + @AutoMetric + private transient long expiredEvents; + + @Override + public void setup(OperatorContext context) + { + sleepMillis = context.getValue(Context.OperatorContext.SPIN_MILLIS); + FileAccessFSImpl fAccessImpl = new TFileImpl.DTFileImpl(); + fAccessImpl.setBasePath(context.getValue(DAG.APPLICATION_PATH) + "/bucket_data"); + managedState.setFileAccess(fAccessImpl); + managedState.setup(context); + + if (preserveTupleOrder) { + decisions = Maps.newLinkedHashMap(); + } + } + + @Override + public void beginWindow(long l) + { + // Reset Metrics + uniqueEvents = 0; + duplicateEvents = 0; + expiredEvents = 0; + + managedState.beginWindow(l); + } + + protected abstract Slice getKey(T event); + + protected abstract long getTime(T event); + + /** + * Processes an incoming tuple + * + * @param tuple + */ + protected void processTuple(T tuple) + { + + long time = getTime(tuple); + Future<Slice> valFuture = managedState.getAsync(time, getKey(tuple)); + + if (valFuture.isDone()) { + try { + processEvent(tuple, valFuture.get()); + } catch (InterruptedException | ExecutionException e) { + throw new RuntimeException(e); + } + } else { + processWaitingEvent(tuple, valFuture); + } + } + + /** + * Processes a looked-up event + * + * @param tuple + * @param value + */ + protected void processEvent(T tuple, Slice value) + { + if (value == BucketedState.EXPIRED) { + processInvalid(tuple); + return; + } + processValid(tuple, value); + } + + /** + * Processes a tuple which is waiting for the lookup to return. + * + * @param tuple The tuple which needs to wait + * @param future The future object which will ultimately return the lookup result + */ + protected void processWaitingEvent(T tuple, Future<Slice> future) + { + waitingEvents.put(tuple, future); + if (preserveTupleOrder) { + recordDecision(tuple, Decision.UNKNOWN); + } + } + + /** + * Processes a valid (non-expired) tuple. This tuple may be a unique or a duplicate. + * + * @param tuple + * The tuple to be processed + * @param value + * Looked up key of the tuple + */ + protected void processValid(T tuple, Slice value) + { + if (!preserveTupleOrder || waitingEvents.isEmpty()) { + if (value == null) { + managedState.put(getTime(tuple), getKey(tuple), getKey(tuple)); + processUnique(tuple); + } else { + processDuplicate(tuple); + } + } else { + processWaitingEvent(tuple, Futures.immediateFuture(value)); + } + } + + /** + * Processes invalid tuples. + * + * @param tuple + */ + protected void processInvalid(T tuple) + { + if (preserveTupleOrder && !decisions.isEmpty()) { + recordDecision(tuple, Decision.EXPIRED); + } else { + processExpired(tuple); + } + } + + /** + * Processes an expired tuple + * + * @param tuple + */ + protected void processExpired(T tuple) + { + expiredEvents++; + emitExpired(tuple); + } + + /** + * Processes the duplicate tuple. + * + * @param tuple + * The tuple which is a duplicate + */ + protected void processDuplicate(T tuple) + { + if (preserveTupleOrder && !decisions.isEmpty()) { + recordDecision(tuple, Decision.DUPLICATE); + } else { + duplicateEvents++; + emitDuplicate(tuple); + } + } + + /** + * Processes the unique tuple. + * + * @param tuple + * The tuple which is a unique + */ + protected void processUnique(T tuple) + { + if (preserveTupleOrder && !decisions.isEmpty()) { + recordDecision(tuple, Decision.UNIQUE); + } else { + uniqueEvents++; + emitUnique(tuple); + } + } + + /** + * {@inheritDoc} + */ + @Override + public void handleIdleTime() + { + if (preserveTupleOrder) { + emitProcessedTuples(); + } + processAuxiliary(false); + } + + /** + * Does any auxiliary processing in the idle time of the operator. + * Processes any tuples which are waiting for the lookup to return. + * + * @param finalize Whether or not to wait for future to return + */ + protected void processAuxiliary(boolean finalize) + { + if (waitingEvents.size() > 0) { + Iterator<Map.Entry<T, Future<Slice>>> waitIterator = waitingEvents.entrySet().iterator(); + while (waitIterator.hasNext()) { + Map.Entry<T, Future<Slice>> waitingEvent = waitIterator.next(); + T tuple = waitingEvent.getKey(); + Slice tupleKey = getKey(tuple); + long tupleTime = getTime(tuple); + Future<Slice> future = waitingEvent.getValue(); + if (future.isDone() || finalize ) { + try { + if (future.get() == null && asyncEvents.get(tupleKey) == null) { + managedState.put(tupleTime, tupleKey, tupleKey); + asyncEvents.put(tupleKey, tupleTime); + processUnique(tuple); + } else { + processDuplicate(tuple); + } + } catch (InterruptedException | ExecutionException e) { + throw new RuntimeException("handle idle time", e); + } + waitIterator.remove(); + } + } + } + } + + @Override + public void endWindow() + { + processAuxiliary(true); + if (preserveTupleOrder) { + emitProcessedTuples(); + } + Preconditions.checkArgument(waitingEvents.isEmpty()); + asyncEvents.clear(); + managedState.endWindow(); + } + + /** + * Records a decision for use later. This is needed to ensure that the order of incoming tuples is maintained. + * + * @param tuple --- End diff -- done > Deduper : create a deduper backed by Managed State > -------------------------------------------------- > > Key: APEXMALHAR-1701 > URL: https://issues.apache.org/jira/browse/APEXMALHAR-1701 > Project: Apache Apex Malhar > Issue Type: Task > Components: algorithms > Reporter: Chandni Singh > Assignee: Chandni Singh > > Need a de-deduplicator operator that is based on Managed State. -- This message was sent by Atlassian JIRA (v6.3.4#6332)