LTSV style access log in tomcat
LTSV + fluentd is nice
LTSV is "Labeled Tab-separated Values", http://ltsv.org/.
A typical access log of Apache is like:
127.0.0.1 - frank [10/Oct/2000:13:55:36 -0700] "GET /apache_pb.gif HTTP/1.0" 200 2326 "http://www.example.com/start.html" "Mozilla/4.08 [en] (Win98; I ;Nav)"
In LTSV, it will be:
host:127.0.0.1<TAB>ident:-<TAB>user:frank<TAB>time:[10/Oct/2000:13:55:36 -0700]<TAB>req:GET /apache_pb.gif HTTP/1.0<TAB>status:200<TAB>size:2326<TAB>referer:http://www.example.com/start.html<TAB>ua:Mozilla/4.08 [en] (Win98; I ;Nav)
Very handleable if using fluentd.
LTSV for access log of tomcat
We can define the pattern of access log with with Value
element of server.xml
.
In detail, see this link http://tomcat.apache.org/tomcat-7.0-doc/config/valve.html#Access_Log_Valve.
We have to write the pattern in attribute of Value element. So if you use tomcat, how do you define your server.xml?
Then use entity 	
like:
<Value ...
pattern="host:%h&#9;ident:%l&#9;user:%u" />
You will get access logs like:
host:127.0.0.1<TAB>ident:-<TAB>user:frank