title: logstash fails to match a grok filter
body: <p>I'm stuck. I cannot get why grok fails to match a simple regex under logstash.
  grok works just fine as a standalone thing.
  The only pattern which works for me is ".*" everything else just fails.</p>
  
  <pre><code>$ cat ./sample2-logstash.conf
  input {
      stdin {}
  }
  
  filter {
      grok {
          match =&gt; [ "message1", "foo.*" ]
          add_tag =&gt; [ "this_is_foo" ]
          tag_on_failure =&gt; [ "STUPID_LOGSTASH" ]
      }
  }
  
  output {
      stdout { codec =&gt; json_lines }
  }
  </code></pre>
  
  <p>Here's the output:</p>
  
  <pre><code>$ echo "foo" |~/bin/logstash-1.4.0/bin/logstash -f ./sample2-logstash.conf 
  {"message":"foo","@version":"1","@timestamp":"2014-05-07T00:32:49.915Z","host":"serega-sv","tags":["STUPID_LOGSTASH"]}
  </code></pre>
  
  <p>Looks like I missed to do something in logstash because vanilla grok works just fine:</p>
  
  <pre><code>$ cat grok.conf
  program {
      file "./sample.log"
      match {
          pattern: "foo.*"
          reaction: "LINE MATCHED! %{@LINE}"
      }
  }
  </code></pre>
  
  <p>Plain grok's output:</p>
  
  <pre><code>$ echo "foo" &gt; ./sample.log; grok -f grok.conf 
  LINE MATCHED! foo
  </code></pre>
  
  <p>Thanks!</p>