[SOLVED] Why does service runs as root while USERNAME is set to something else

Why does service runs as root while USERNAME is set to something else

I am setting up a Linux service for my Python app using Upstart. Here is the conf file in /etc/init/

description "AAE client app"

start on runlevel [2345]
stop on runlevel [!2345]

respawn

env PATH=/home/ec2-user/aae_client/env/bin
env PROGRAM_NAME="aae"
env USERNAME="ec2-user"

# Main script to be run
script
    echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (sys) Ready to run..." >> /var/log/$PROGRAM_NAME.sys.log

    export HOME="/home/ec2-user"
    echo $$ > /var/run/$PROGRAM_NAME.pid

    cd /home/ec2-user/aae_client
    exec python -m app.run >> /var/log/$PROGRAM_NAME.sys.log 2>&1
end script

I already set the USERNAME to ec2-user. However when I run the service, it shows it is run by root. Apparently other variables such as PATH are set correctly. Why does it still run as root when USERNAME is specified?

Solution

Changing USERNAME or even the canonical USER variable does not change the context the processes run in. Have a look at the solutions over at SuperUser.