How to escape ${PROGRAM} in syslog-ng destination file path

Question

I have syslog-ng 4.1 as syslog collector with configuration for remote logs storage

destination d_remote_logs {
    file(
        "/var/log/remote/${HOST_FROM}-${PROGRAM}.log"
        template("$(format-json --scope nv-pairs)\n")
        perm(0644)
    );
};

But some apps send ${PROGRAM} tag like a "postfix/smtp" and logs save to

/var/log/remote/192.168.10.50-postfix/smtp.log

How to escape '/' or replace it to '_' for destination file name set as

/var/log/remote/192.168.10.50-postfix_smtp.log

Answer 1

Use replace() to change characters. In your case, you can replace the / character with _ in the ${PROGRAM}.

Here is the sample:

destination d_remote_logs {
    file(
        "/var/log/remote/${HOST_FROM}-$(replace (\"/\", \"_\", \"${PROGRAM}\")).log"
        template("$(format-json --scope nv-pairs)\n")
        perm(0644)
    );
};