iCALL and Cert expiry dates

Here is the final code. periodic handler is calling the script every day. you can activate the script with "generate sys icall event CHECK_CERT". If cert is close to 45 days, log will be send in /var/log/ltm that you can syslog to you supervision infrastructure.

sys icall handler periodic certificate_periodic_handler {
    first-occurrence 2014-09-26:21:57:49
    interval 86400
    script monitor_certificate
}
sys icall handler triggered certificate_handler {
    script monitor_certificate
    subscriptions {
        sub1 {
            event-name CHECK_CERT
        }
    }
}
sys icall script monitor_certificate {
    app-service none
    definition {
        set current_date [exec date +%s]
        puts "date: $current_date"
        date offset for 45 days : 45x24x60x60 = 3888000
        set date_offset 3888000
        foreach certificate [tmsh::get_config sys crypto cert] {
            set expiration [tmsh::get_field_value $certificate "expiration"]
            puts "expiration: $expiration"
            set exp_unix [exec date --date=$expiration +"%s"]
            puts "exp unix: $exp_unix"
            set cert_name [tmsh::get_name $certificate]
            if { [expr ($exp_unix - $date_offset) < $current_date] }            {
                puts "cert warning: $cert_name close to expiration date"
                exec logger -p local0.notice "Certificate Warning: $cert_name close to expiration date"
            } else {
                puts "cert ok: $cert_name"
            }
        }
    }
    description none
    events none
}