# Title:   supervisor environment varaibles broken on ubuntu18.04
# Subject: the packaged supervisor-3.3.1 does not respect environemtn variables

I am using supervisor to manage a few daemons.
I use environemnt variables to avoid hard coding paths.

Supervisor-3.2 and newer support this:
Environemnt variable X is accessable in supervisor config file via %(ENV_X)s

I installed supervisor 3.3.1-1.1 via the ubuntu 18.04 lts package
 apt install supervisor

This generated the following files in etc:
1. /etc/init.d/supervisor             
2. /etc/systemd/system/multi-user.target.wants/supervisor.service
3. /etc/supervisor/supervisord.conf
4. /etc/supervisor/conf.d
5. /etc/default/supervisor

Description of files:
1. is the legacy non-systemd init (not used)
2. is the systemd init (is used)
3. is the supervisor daemon config
4. is directory holing supervised damon configs
5. is an environemnet file, not used by systemd.

I must be able to feed environment variables to supervisord.

The file /etc/default/supervisor is there to serve this purpose:
sudo vi /etc/default/supervisor
Add:
 INST_USER="my_user"
 INST_PATH="/var/www/wsgi/app"

I see /etc/init.d/supervisor sources /etc/default/supervisor.

Problem:
The systemd service file ignores /etc/default/supervisor.

Solution:
Edit the systemd service file, and add a line to look at /etc/default/supervisor
sudo vi /etc/systemd/system/multi-user.target.wants/supervisor.service
 Under: [Service]
 Add: EnvironmentFile=-/etc/default/supervisor
systemctl daemon-reload
systemctl restart supervisor
systemctl status supervisor