Comment 6 for bug 1883656

Having /etc/juju-proxy.conf written to would only give us a way to write wrappers that would allow sourcing proxy variables for:

* cron jobs or timers;
  * which is what we have with glance-simplestreams-sync;
* software that periodically executes subprocesses (through wrappers that would load /etc/juju-proxy.conf).

For services that require a manual restart or reload to see a change to settings in /etc/juju-proxy.conf we would still need a hook to fire to make a charm do a restart/reload of the necessary services.

In summary:

* for the purposes of glance-simplestreams-sync, the easiest would be to have /etc/juju-proxy.conf written to via cloudinit-userdata/proxy updater since we use a cron job;
* writing proxy settings to a file such as /etc/glance-simplestreams-sync.conf would not solve the problem with asynchronous updates to proxy settings - we need hooks to fire for that.