cloudfoundry.norouter.f5.dropsonde.LineEventDecoder.java Source code

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Here is the source code for cloudfoundry.norouter.f5.dropsonde.LineEventDecoder.java

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/*
 * Copyright (c) 2015 Intellectual Reserve, Inc.  All rights reserved.
 *
 *    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 cloudfoundry.norouter.f5.dropsonde;

import cloudfoundry.norouter.NorouterUtil;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.DecoderException;
import io.netty.handler.codec.MessageToMessageDecoder;

import java.net.InetSocketAddress;
import java.nio.charset.StandardCharsets;
import java.time.Instant;
import java.util.List;
import java.util.UUID;

/**
 * @author Mike Heath
 */
public class LineEventDecoder extends MessageToMessageDecoder<ByteBuf> {

    @Override
    protected void decode(ChannelHandlerContext context, ByteBuf buffer, List<Object> out) throws Exception {
        buffer.markReaderIndex();
        try {
            final String command = nextString(buffer);
            // Extract event type
            switch (command) {
            case "LOG":
                decodeLogEvent(context, buffer, out);
                break;
            default:
                throw new IllegalStateException("Unknown command " + command);
            }
        } catch (Exception e) {
            buffer.resetReaderIndex();
            throw new DecoderException("Invalid line event: " + buffer.toString(StandardCharsets.UTF_8), e);
        }
    }

    private String nextString(ByteBuf buffer) {
        // Read space terminated string
        final int start = buffer.readerIndex();
        int length = 0;
        while (buffer.readByte() != ' ') {
            length++;
        }
        return buffer.toString(start, length, StandardCharsets.UTF_8);
    }

    private void decodeLogEvent(ChannelHandlerContext context, ByteBuf buffer, List<Object> out) {
        final String ltmIdentifier = nextString(buffer);
        final String address = nextString(buffer);
        final String timestamp = nextString(buffer);
        final String requestId = nextString(buffer);
        final String message = buffer.toString(StandardCharsets.UTF_8);
        out.add(new LogEvent(ltmIdentifier, NorouterUtil.toSocketAddress(address),
                Instant.ofEpochMilli(Long.valueOf(timestamp)), UUID.fromString(requestId), message));
    }

}