zipkin.storage.elasticsearch.ElasticsearchSpanConsumer.java Source code

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Here is the source code for zipkin.storage.elasticsearch.ElasticsearchSpanConsumer.java

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/**
 * Copyright 2015-2016 The OpenZipkin Authors
 *
 * 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 zipkin.storage.elasticsearch;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.util.concurrent.Futures;
import com.google.common.util.concurrent.ListenableFuture;
import java.io.IOException;
import java.util.List;
import java.util.concurrent.TimeUnit;
import zipkin.Span;
import zipkin.storage.elasticsearch.InternalElasticsearchClient.BulkSpanIndexer;
import zipkin.storage.guava.GuavaSpanConsumer;

import static com.google.common.util.concurrent.Futures.immediateFuture;
import static zipkin.internal.ApplyTimestampAndDuration.guessTimestamp;

final class ElasticsearchSpanConsumer implements GuavaSpanConsumer {
    private static final byte[] TIMESTAMP_MILLIS_PREFIX = "{\"timestamp_millis\":".getBytes();
    private static final ListenableFuture<Void> VOID = immediateFuture(null);

    private final InternalElasticsearchClient client;
    private final IndexNameFormatter indexNameFormatter;

    ElasticsearchSpanConsumer(InternalElasticsearchClient client, IndexNameFormatter indexNameFormatter) {
        this.client = client;
        this.indexNameFormatter = indexNameFormatter;
    }

    @Override
    public ListenableFuture<Void> accept(List<Span> spans) {
        if (spans.isEmpty())
            return VOID;
        try {
            return indexSpans(client.bulkSpanIndexer(), spans).execute();
        } catch (Exception e) {
            return Futures.immediateFailedFuture(e);
        }
    }

    BulkSpanIndexer indexSpans(BulkSpanIndexer indexer, List<Span> spans) throws IOException {
        for (Span span : spans) {
            Long timestamp = guessTimestamp(span);
            Long timestampMillis;
            String index; // which index to store this span into
            if (timestamp != null) {
                timestampMillis = TimeUnit.MICROSECONDS.toMillis(timestamp);
                index = indexNameFormatter.indexNameForTimestamp(timestampMillis);
            } else {
                timestampMillis = null;
                index = indexNameFormatter.indexNameForTimestamp(System.currentTimeMillis());
            }
            indexer.add(index, span, timestampMillis);
        }
        return indexer;
    }

    /**
     * In order to allow systems like Kibana to search by timestamp, we add a field "timestamp_millis"
     * when storing. The cheapest way to do this without changing the codec is prefixing it to the
     * json. For example. {"traceId":"... becomes {"timestamp_millis":12345,"traceId":"...
     */
    @VisibleForTesting
    static byte[] prefixWithTimestampMillis(byte[] input, long timestampMillis) {
        String dateAsString = Long.toString(timestampMillis);
        byte[] newSpanBytes = new byte[TIMESTAMP_MILLIS_PREFIX.length + dateAsString.length() + input.length];
        int pos = 0;
        System.arraycopy(TIMESTAMP_MILLIS_PREFIX, 0, newSpanBytes, pos, TIMESTAMP_MILLIS_PREFIX.length);
        pos += TIMESTAMP_MILLIS_PREFIX.length;
        for (int i = 0, length = dateAsString.length(); i < length; i++) {
            newSpanBytes[pos++] = (byte) dateAsString.charAt(i);
        }
        newSpanBytes[pos++] = ',';
        // starting at position 1 discards the old head of '{'
        System.arraycopy(input, 1, newSpanBytes, pos, input.length - 1);
        return newSpanBytes;
    }
}