logo标签列表

编写自定义的Flume修饰器，但是出现了错误。我漏掉了什么？

javaflume
4

我正在为Cloudera的分布式日志聚合系统Flume编写自定义装饰器插件，以下是我的Java代码：

package multiplex;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import com.cloudera.flume.conf.Context;
import com.cloudera.flume.conf.SinkFactory.SinkDecoBuilder;
import com.cloudera.flume.core.Event;
import com.cloudera.flume.core.EventImpl;
import com.cloudera.flume.core.EventSink;
import com.cloudera.flume.core.EventSinkDecorator;
import com.cloudera.util.Pair;
import com.google.common.base.Preconditions;

public class JsonMultiplexDecorator<S extends EventSink> extends EventSinkDecorator<S> {
  private final String serverName;
  private final String logType;

  public JsonMultiplexDecorator(S s, String serverName, String logType) {
    super(s);

    this.serverName = serverName;
    this.logType = logType;
  }

  @Override
  public void append(Event e) throws IOException {
    String body = new String(e.getBody()).replaceAll("\"", "\\\"");

    String json = "{ \"server\": \"" + this.serverName + "\"," +
      "\"log_type\": \"" + this.logType + "\", " +
      "\"body\": \"" + body + "\" }";

    EventImpl e2 = new EventImpl(json.getBytes(),
        e.getTimestamp(), e.getPriority(), e.getNanos(), e.getHost(),
        e.getAttrs());

    super.append(e2);
  }

  public static SinkDecoBuilder builder() {
    return new SinkDecoBuilder() {
      @Override
      public EventSinkDecorator<EventSink> build(Context context,
          String... argv) {
        Preconditions.checkArgument(argv.length == 2,
            "usage: multiplexDecorator(serverName, logType)");

        return new JsonMultiplexDecorator<EventSink>(null, argv[0], argv[1]);
      }
    };
  }

  public static List<Pair<String, SinkDecoBuilder>> getDecoratorBuilders() {
    List<Pair<String, SinkDecoBuilder>> builders = 
      new ArrayList<Pair<String, SinkDecoBuilder>>();

    builders.add(new Pair<String, SinkDecoBuilder>("jsonMultiplexDecorator", builder()));

    return builders;
  }
}

使用ant可以将其编译为JAR文件，我可以在运行时将其加载到Flume中，并成功配置节点以使用它。但是，当实际上有事件通过加载了此插件的节点时，我的日志中会出现如下错误：

2010-10-19 21:03:15,176 [logicalNode xxxxx] ERROR connector.DirectDriver: Driving src/sink failed! LazyOpenSource | LazyOpenDecorator because null
java.lang.UnsupportedOperationException
    at java.util.Collections$UnmodifiableMap.put(Collections.java:1285)
    at com.cloudera.flume.core.EventBaseImpl.set(EventBaseImpl.java:65)
    at com.cloudera.flume.handlers.rolling.RollSink.append(RollSink.java:164)
    at com.cloudera.flume.agent.diskfailover.DiskFailoverDeco.append(DiskFailoverDeco.java:93)
    at com.cloudera.flume.core.BackOffFailOverSink.append(BackOffFailOverSink.java:144)
    at com.cloudera.flume.agent.AgentSink.append(AgentSink.java:109)
    at com.cloudera.flume.core.EventSinkDecorator.append(EventSinkDecorator.java:58)
    at multiplex.JsonMultiplexDecorator.append(JsonMultiplexDecorator.java:56)
    at com.cloudera.flume.core.EventSinkDecorator.append(EventSinkDecorator.java:58)
    at com.cloudera.flume.handlers.debug.LazyOpenDecorator.append(LazyOpenDecorator.java:69)
    at com.cloudera.flume.core.connector.DirectDriver$PumperThread.run(DirectDriver.java:92)

([logicalNode xxxxx] 是 EC2 内部 DNS 名称的占位符)。我没有很多 Java 经验，所以我不确定我在这里做错了什么，或者这是 Flume 的 bug。我应该提到，我是使用 Flume 源代码中的 HelloWorld 插件示例编写的，并且参考了一些内置的 Flume 装饰器。

2
只是一点提醒，你不觉得使用 JSON API 比使用这些令人困惑的字符串拼接更好吗？ - Marcos Vasconcelos
@Marcos 是的，我也这样认为。我已经修改了这个插件，以及 phooji 在下面提出的解决方案。本帖中的代码示例相当过时 :) - Josh Lindsey
1个回答
2
网页内容由stack overflow 提供, 点击上面的
可以查看英文原文，
原文链接