collect access.log to docker log driver

[1026524749]

Tomcat catalina.log is collected to stdout，but access.log is output to file in the container。
How do I to collect access.log by docker log driver？

[tianon]

I think the following section in the default conf/server.xml is probably relevant:

        <!-- Access log processes all example.
             Documentation at: /docs/config/valve.html
             Note: The pattern used is equivalent to using pattern="common" -->
        <Valve className="org.apache.catalina.valves.AccessLogValve" directory="logs"
               prefix="localhost_access_log" suffix=".txt"
               pattern="%h %l %u %t &quot;%r&quot; %s %b" />

If all else fails, you could create a short Dockerfile that's FROM tomcat:X.Y which creates a symlink from the access log file to /dev/stdout (like NGINX does: https://github.com/nginxinc/docker-nginx/blob/48a4c531fc4bfa80d4270f20a67e2e958856860c/stable/stretch/Dockerfile#L91-L93).

[srossross]

I've modified my conf/server.xml, this works for me:

        <Valve className="org.apache.catalina.valves.AccessLogValve" directory="/proc/self/fd"
               prefix="1" suffix="" rotatable="false"
               pattern="%h %l %u %t &quot;%r&quot; %s %b" />

[tianon]

Nice, thanks for confirming @srossross! 👍

[connachtguy]

I've modified my conf/server.xml, this works for me:

        <Valve className="org.apache.catalina.valves.AccessLogValve" directory="/proc/self/fd"
               prefix="1" suffix="" rotatable="false"
               pattern="%h %l %u %t &quot;%r&quot; %s %b" />

I have a containerized app that spews it's log messages to standard out. It runs on tomcat, and we created a symbolic link from the tomcat access log to /dev/stdout which seemed to work, but we found that occasionally the application messages were clashing with the access log messages. I'm wondering if there's any reason to think this /proc/self/fd approach would be any better?

[arulrajnet]

In server.xml

<Valve className="org.apache.catalina.valves.AccessLogValve" 
            directory="/dev" prefix="stdout" suffix="" pattern="%h %l %u %t &quot;%r&quot; %s %b" 
            buffered="false" fileDateFormat=""/>

This sends the accesslog into stdout.