help writing a service file for dropbox

[SternData]

There's an init.d file for Dropbox for non-GUI servers. I'd like to use
drobpox as a way to understand systemd a little better.

In the init.d file, it pulls in a list of users from /etc/sysconfig.
I'm trying to figure out how to do something like that with a service file.

My dropbox.service file is:

cat /etc/systemd/system/dropbox.service

---------------------------------------

[Unit]
Description=Dropbox as a system service

[Service]
ExecStart=/home/sdstern/.dropbox-dist/dropboxd
User=sdstern
# 'LANG' might be unnecessary, since systemd already sets the
# locale for all services according to "/etc/locale.conf".
# Run `systemctl show-environment` to make sure.
Environment=LANG=en_US.utf-8

[Install]
WantedBy=multi-user.target

---------------------------------------

Ideally, I'd look at a list of users entered in a file in /etc/sysconfig
and loop through ExecStart and User for each user, substituting the user
name for "sdstern" on each.

So, pointers on how to do things like this in a .service file?

[Richard Shaw]

On Sun, Aug 24, 2014 at 10:38 AM, Steven Stern <
[e-mail]> wrote:
> Ideally, I'd look at a list of users entered in a file in /etc/sysconfig
> and loop through ExecStart and User for each user, substituting the user
> name for "sdstern" on each.
>
> So, pointers on how to do things like this in a .service file?
>
> I don't think a dropbox like service really lends itself to system-wide

startup. What if one of your users isn't signed up, or doesn't want to be?

Richard

[SternData]

On 08/24/2014 08:52 PM, Richard Shaw wrote:
> On Sun, Aug 24, 2014 at 10:38 AM, Steven Stern
> <[e-mail] >
> wrote:
> Ideally, I'd look at a list of users entered in a file in /etc/sysconfig
> and loop through ExecStart and User for each user, substituting the user
> name for "sdstern" on each.
>
> So, pointers on how to do things like this in a .service file?
>
> I don't think a dropbox like service really lends itself to system-wide
> startup. What if one of your users isn't signed up, or doesn't want to be?

That's the function of the file in /etc/sysconfig. It lists the users
who are.  Actually, this is just my system but I run a couple of dropbox
user accounts on it -- one as my main one and one to backup client websites.

[Dan Mossor]

On 08/24/2014 08:52 PM, Richard Shaw wrote:
> On Sun, Aug 24, 2014 at 10:38 AM, Steven Stern
> <[e-mail] >
> wrote:
> Ideally, I'd look at a list of users entered in a file in /etc/sysconfig
> and loop through ExecStart and User for each user, substituting the user
> name for "sdstern" on each.
>
> So, pointers on how to do things like this in a .service file?
>
> I don't think a dropbox like service really lends itself to system-wide
> startup. What if one of your users isn't signed up, or doesn't want to be?
>
> Richard

Then the service file simply runs an if/then loop, only initiating for 
users that have ~/.dropbox-dist/ directory.

[SternData]

On 09/22/2014 09:18 AM, Dan Mossor wrote:
> On 08/24/2014 08:52 PM, Richard Shaw wrote:
> > On Sun, Aug 24, 2014 at 10:38 AM, Steven Stern
> > <[e-mail] >
> > wrote:
> > Ideally, I'd look at a list of users entered in a file in
> >
> > /etc/sysconfig
> >     and loop through ExecStart and User for each user, substituting
> > the user
> >     name for "sdstern" on each.
> > So, pointers on how to do things like this in a .service file?
> >
> > I don't think a dropbox like service really lends itself to system-wide
> > startup. What if one of your users isn't signed up, or doesn't want to
> > be?
> >
> > Richard
>
> Then the service file simply runs an if/then loop, only initiating for
> users that have ~/.dropbox-dist/ directory.

Can I treat a .service file like a bash script and  do all those "loop"
sorts of things?

[T.C. Hollingsworth]

On Mon, Sep 22, 2014 at 12:40 PM, Steven Stern
 wrote:
> Can I treat a .service file like a bash script and  do all those "loop"
> sorts of things?

No, but you can invoke a bash script from a service file that does
things in a loop.  But that doesn't buy you much^D anything really
over the initial initscript.  ;-)

A proper systemdish way to accomplish this would be to use an instance
service for dropbox and use the standard systemd tools to
enable/disable it for particular users instead of keeping the list in
an /etc/sysconfig file.

First, I'd suggest reading this nice introduction to instance
services; it's not very long and afterward you'll have a full
understanding of what's going on with my example below:
http://0pointer.de/blog/projects/instances.html

To create an instance service for dropbox, instead of using
"dropbox.service", create a "dropbox@.service" file (the @ is very
important), with the following contents:
--
[Unit]
Description=Dropbox service for user %I

[Service]
ExecStart=/home/%i/.dropbox-dist/dropboxd
User=%i

[Install]
WantedBy=multi-user.target

--

Once you have that, instead of managing the users it is started for
with a file in /etc/sysconfig, just use systemctl to enable/disable it
for users as appropriate.

To enable the dropbox service for the "sdstern" user:
# systemctl enable [e-mail]

To disable the dropbox service for the "sdstern" user later on:
# systemctl disable [e-mail]

And, to see all the users dropbox is enabled for:
% ls /etc/systemd/system/multi-user.target.wants/dropbox@*

-T.C.