title: Subset of tag to a second output
body: <p>I've got a service I'm trying to record logs from and send them to certain locations depending on what they refer to. Fluentd makes sense. Currently, I just have everything being chucked off to s3, and that works fine. However I now want a small subset (any line beginning with the phrase "ACTION:") to also be sent to a mongo database. I still want everything sent to s3.</p>
  
  <p>I have this config file here, which of course isn't going to work</p>
  
  <pre><code>&lt;source&gt;
    @type  forward
    @id    input
    @label mainstream
    port   24224
  &lt;/source&gt;
  
  &lt;label @mainstream&gt;
  
    &lt;match foo.**&gt;
      @type copy
  
      &lt;store&gt;
        @type s3
  
        ...
      &lt;/store&gt;
      &lt;store&gt;
        @type rewrite_tag_filter
        rewriterule1 log "^ACTION:" foo.bar
      &lt;/store&gt;
  
    &lt;/match&gt;
  
    &lt;match foo.bar&gt;
      @type mongo
  
      ...
    &lt;/matc&gt;
  &lt;/label&gt;
  </code></pre>
  
  <p>It's all going to be collected and stopped once we've got to the first match tag, the normal behaviour of the <code>rewrite_tag_filter</code> doesn't seem to pass on past the <code>&lt;store&gt;</code>.</p>
  
  <p>Other things I've tried.</p>
  
  <ul>
  <li>Copying the s3 <code>store</code> so it's used twice. However I don't want my s3 outputs to be split.</li>
  <li>Forward to itself at a different port, run the source through a different label, however it wouldn't connect.</li>
  </ul>
  
  <p>I'm sure what I'm asking isn't too insane. Has anyone done something like this before?</p>