com.ikanow.aleph2.graph.titan.services.SimpleGraphMergeService.java Source code

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Here is the source code for com.ikanow.aleph2.graph.titan.services.SimpleGraphMergeService.java

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/*******************************************************************************
 * Copyright 2016, The IKANOW Open Source Project.
 *
 * Licensed 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 com.ikanow.aleph2.graph.titan.services;

import java.util.LinkedList;
import java.util.List;
import java.util.Optional;
import java.util.stream.Stream;

import scala.Tuple2;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.ikanow.aleph2.data_model.interfaces.data_analytics.IBatchRecord;
import com.ikanow.aleph2.data_model.interfaces.data_import.IEnrichmentBatchModule;
import com.ikanow.aleph2.data_model.interfaces.data_import.IEnrichmentModuleContext;
import com.ikanow.aleph2.data_model.objects.data_import.DataBucketBean;
import com.ikanow.aleph2.data_model.objects.data_import.EnrichmentControlMetadataBean;
import com.ikanow.aleph2.data_model.objects.data_import.GraphAnnotationBean;
import com.ikanow.aleph2.data_model.objects.shared.BasicMessageBean;
import com.ikanow.aleph2.data_model.utils.SetOnce;

import fj.data.Validation;

/** Very simple code that "merges" matching vertices and edges (just picks the first one it sees)
 * @author Alex
 */
public class SimpleGraphMergeService implements IEnrichmentBatchModule {

    protected SetOnce<IEnrichmentModuleContext> _context = new SetOnce<>();

    /* (non-Javadoc)
     * @see com.ikanow.aleph2.data_model.interfaces.data_import.IEnrichmentBatchModule#onStageInitialize(com.ikanow.aleph2.data_model.interfaces.data_import.IEnrichmentModuleContext, com.ikanow.aleph2.data_model.objects.data_import.DataBucketBean, com.ikanow.aleph2.data_model.objects.data_import.EnrichmentControlMetadataBean, scala.Tuple2, java.util.Optional)
     */
    @Override
    public void onStageInitialize(IEnrichmentModuleContext context, DataBucketBean bucket,
            EnrichmentControlMetadataBean control, Tuple2<ProcessingStage, ProcessingStage> previous_next,
            Optional<List<String>> next_grouping_fields) {
        _context.set(context);
    }

    /* (non-Javadoc)
     * @see com.ikanow.aleph2.data_model.interfaces.data_import.IEnrichmentBatchModule#onObjectBatch(java.util.stream.Stream, java.util.Optional, java.util.Optional)
     */
    @Override
    public void onObjectBatch(Stream<Tuple2<Long, IBatchRecord>> batch, Optional<Integer> batch_size,
            Optional<JsonNode> grouping_key) {

        // (some horrible mutable state to keep this simple)
        final LinkedList<Tuple2<Long, IBatchRecord>> mutable_user_elements = new LinkedList<>();

        final Optional<Validation<BasicMessageBean, JsonNode>> output = batch.filter(t2 -> {
            if (!t2._2().injected() && mutable_user_elements.isEmpty()) { // (save one element per label in case there are no injected elements)
                mutable_user_elements.add(t2);
            }
            return t2._2().injected();
        }).filter(t2 -> {
            final ObjectNode o = (ObjectNode) t2._2().getJson();
            return Optional.ofNullable(o.get(GraphAnnotationBean.type)).filter(j -> (null != j) && j.isTextual())
                    .map(j -> j.asText()).map(type -> {
                        if (GraphAnnotationBean.ElementType.edge.toString().equals(type)) {
                            // Return the first matching edge:
                            return true;
                        } else if (GraphAnnotationBean.ElementType.vertex.toString().equals(type)) {
                            // Return the first matching vertex:
                            return true;
                        } else
                            return false;
                    }).orElse(false);
        }).findFirst().<Validation<BasicMessageBean, JsonNode>>map(
                element -> _context.get().emitImmutableObject(_context.get().getNextUnusedId(),
                        element._2().getJson(), Optional.empty(), Optional.empty(), Optional.empty()));

        if (!output.isPresent()) { // If didn't find any matching elements, then stick the first one we did find in there
            mutable_user_elements.forEach(t2 -> _context.get().emitImmutableObject(t2._1(), t2._2().getJson(),
                    Optional.empty(), Optional.empty(), Optional.empty()));
        }
    }

    /* (non-Javadoc)
     * @see com.ikanow.aleph2.data_model.interfaces.data_import.IEnrichmentBatchModule#onStageComplete(boolean)
     */
    @Override
    public void onStageComplete(boolean is_original) {
        // (Currently nothing to do)
    }

}