Custom Apache-style logging for Java-based applications

Problem this snippet solves:

I had a requirement to have the F5 BigIP produce logs which replicated our current custom Apache Logs. The Apache custom log format was:

CustomLog /../apache/logs/ssl_request_log "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" 
  \"%{User-Agent}i\" %T %{JSESSIONID}C %{SSL_PROTOCOL}x %{SSL_CIPHER}x %D"

This was used for logging a Tomcat based web application. We have scripts which parse through the logs and create .csv baed documents to aid in the creation of reports (hence the use of commas as separators and quotations around values which could contain commas such as URLs and SessionIDs). Thanks to a lot of help from the contributors at the forums here I have had success.

I hope you find this useful.

Code :

when HTTP_REQUEST {
  set http_request_time [clock clicks -milliseconds]
  set request_log_line "\
[HTTP::request_num],\
[IP::remote_addr],\
[HTTP::method],\
[HTTP::version],\
[HTTP::host],\
\"[HTTP::uri]\",\
\"[HTTP::header value Referer]\",
\"[HTTP::header User-Agent]\",\
\"[HTTP::cookie value JSESSIONID]\",\
[SSL::cipher name],\
[SSL::cipher version],\
[SSL::cipher bits]"
}

when HTTP_RESPONSE {
  set http_response_time [ clock clicks -milliseconds ]
  log local0. "$request_log_line,\
[HTTP::status],\
[HTTP::payload length],\
[expr $http_response_time - $http_request_time]"
}