com.uber.jaeger.senders.UDPSender.java Source code

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Here is the source code for com.uber.jaeger.senders.UDPSender.java

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/*
 * Copyright (c) 2016, Uber Technologies, Inc
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.uber.jaeger.senders;

import com.twitter.zipkin.thriftjava.Span;
import com.uber.jaeger.agent.thrift.Agent;
import com.uber.jaeger.exceptions.SenderException;
import com.uber.jaeger.reporters.protocols.TUDPTransport;
import org.apache.thrift.TException;
import org.apache.thrift.protocol.TCompactProtocol;
import org.apache.thrift.transport.AutoExpandingBufferWriteTransport;

import java.util.ArrayList;
import java.util.List;
import lombok.ToString;

@ToString(exclude = { "spanBuffer", "udpClient", "memoryTransport" })
public class UDPSender implements Sender {
    final static int emitZipkinBatchOverhead = 22;
    private static final String defaultUDPSpanServerHost = "localhost";
    private static final int defaultUDPSpanServerPort = 5775;
    private static final int defaultUDPPacketSize = 65000;

    private int maxSpanBytes;
    private Agent.Client udpClient;
    private List<Span> spanBuffer;
    private int byteBufferSize;
    private AutoExpandingBufferWriteTransport memoryTransport;
    private TUDPTransport udpTransport;

    public UDPSender(String host, int port, int maxPacketSize) {
        if (host == null || host.length() == 0) {
            host = defaultUDPSpanServerHost;
        }

        if (port == 0) {
            port = defaultUDPSpanServerPort;
        }

        if (maxPacketSize == 0) {
            maxPacketSize = defaultUDPPacketSize;
        }

        memoryTransport = new AutoExpandingBufferWriteTransport(maxPacketSize, 2);

        udpTransport = TUDPTransport.NewTUDPClient(host, port);
        udpClient = new Agent.Client(new TCompactProtocol(udpTransport));
        maxSpanBytes = maxPacketSize - emitZipkinBatchOverhead;
        spanBuffer = new ArrayList<>();
    }

    int getSizeOfSerializedSpan(Span span) throws SenderException {
        memoryTransport.reset();
        try {
            span.write(new TCompactProtocol(memoryTransport));
        } catch (TException e) {
            throw new SenderException("UDPSender failed writing to memory buffer.", e, 1);
        }
        return memoryTransport.getPos();
    }

    /*
     * Adds spans to an internal queue that flushes them as udp packets later.
     * This function does not need to be synchronized because the reporter creates
     * a single thread that calls this append function
     */
    @Override
    public int append(Span span) throws SenderException {
        int spanSize = getSizeOfSerializedSpan(span);
        if (spanSize > maxSpanBytes) {
            throw new SenderException("UDPSender received a span that was too large", null, 1);
        }

        byteBufferSize += spanSize;
        if (byteBufferSize <= maxSpanBytes) {
            spanBuffer.add(span);
            if (byteBufferSize < maxSpanBytes) {
                return 0;
            }
            return flush();
        }

        int n;
        try {
            n = flush();
        } catch (SenderException e) {
            // +1 for the span not submitted in the buffer above
            throw new SenderException(e.getMessage(), e.getCause(), e.getDroppedSpanCount() + 1);
        }

        spanBuffer.add(span);
        byteBufferSize = spanSize;
        return n;
    }

    @Override
    public int flush() throws SenderException {
        if (spanBuffer.isEmpty()) {
            return 0;
        }

        int n = spanBuffer.size();
        try {
            udpClient.emitZipkinBatch(spanBuffer);
        } catch (TException e) {
            throw new SenderException("Failed to flush spans.", e, n);
        } finally {
            spanBuffer.clear();
            byteBufferSize = 0;
        }
        return n;
    }

    @Override
    public int close() throws SenderException {
        int n = flush();
        udpTransport.close();
        return n;
    }
}