title: logstash - geoip in Kibana can not show any information using the IP addresses
body: <p>I want to display the number of users accessing my app in a World Map using ElasticSearch, Kibana and Logstash.</p>
  
  <p>Here is my log (Json format):</p>
  
  <pre><code>{
    "device": "",
    "public_ip": "70.90.17.210",
    "mac": "00:01:02:03:04:05",
    "ip": "192.16.1.10",
    "event": {
      "timestamp": "2014-08-15T00:00:00.000Z",
      "source": "system",
      "name": "status"
    },
    "status": {
      "channel": "channelname",
      "section": "pictures",
      "downlink": 1362930,
      "network": "Wi-Fi"
    }
  }
  </code></pre>
  
  <p>And this is my config file:</p>
  
  <pre><code>input {
    file { 
      path =&gt; ["/mnt/logs/stb.events"]
      codec =&gt; "json" 
      type =&gt; "event" 
    }
  }
  filter {
      date    {
          match =&gt; [ "timestamp", "yyyy-MM-dd HH:mm:ss", "ISO8601" ]
      }
  }
  
  filter {
      mutate  {
          convert =&gt; [ "downlink", "integer" ]
      }
  }
  filter {
      geoip {
        add_tag =&gt; [ "geoip" ]
        database =&gt; "/opt/logstash/vendor/geoip/GeoLiteCity.dat" 
        source =&gt; "public_ip"
        target =&gt; "geoip"
        add_field =&gt; [ "[geoip][coordinates]", "%{[geoip][longitude]}" ]
        add_field =&gt; [ "[geoip][coordinates]", "%{[geoip][latitude]}" ]
            }
      mutate {
        convert =&gt; [ "[geoip][coordinates]", "float" ]
      }
  }
  output { 
    elasticsearch {
      host =&gt; localhost
    }
  }
  </code></pre>
  
  <p>At the end in Kibana I see only an empty geoip tag</p>
  
  <p>Can someone help me and to point me where is my mistake?</p>