Systemd startup Broadway backend

[Ronald Skeoch]

I met a problem to use systemd to startup a program which needs to talk to GDK Broadway backend.

(We are prepared to contribute $Aus 1000 for speedy fix.)
Is this the correct location?

The whole story is that I am in the progress to migrate a GTK+3 application to web based on Nignx/Nodejs/Broadway. Using systemd to startup a Nodejs application which will "spawn" a Broadway instance and a GTK+3 application when user logins in. And the GTK+3 application will "display" on that Broadway instance.

Interesting thing is that when I execute that Nodejs application through terminal, everything works perfectly.

When I use systemd to startup that Nodejs application, after user logins in, Broadway instance is up, the GTK+3 application is up then exit with the error message: "Gtk-WARNING **: cannot open display:"

I googled for a while and didn't find many useful information. So I am not sure it is that systemd doesn't support GUI or I just made a stupid mistake.

Anyway, thanks a lot in advance.

The systemd service file of the Nodejs application looks like this:

[Unit]
Description=XXXXXXXXX
After=Our-Nginx.service

[Service]
ExecStart=/usr/bin/nodejs /path/to/Nodejs/application
Restart=always
RestartSec=5
StandardOutput=syslog
StandardError=syslog
SyslogIdentifier=Nodejs_application

[Install]
WantedBy=multi-user.target

The Nodejs application code looks like this:

... ...

var spawn = require('child_process').spawn;

... ...

var env = Object.create(process.env);
env.LOGNAME = username;
env.GDK_BACKEND = 'broadway';
env.BROADWAY_DISPLAY = port_id;
env.SAL_USE_VCLPLUGIN = 'gtk3';
env.UBUNTU_MENUPROXY = '';
env.LIBOVERLAY_SCROLLBAR = '';
env.HOME = 'XXXXXXX';

const instance = spawn('/path/to/gtk3/application', [], { env: env });
instance.stdout.on('data', (data) => {
      console.log(`stdout: ${data}`);
});

instance.stderr.on('data', (data) => {
      console.log(`stderr: ${data}`);
});
instance.on('close', (code) => {
      console.log(`child process exited with code ${code}`);
});

[Gunnar Hjalmarsson (gunnarhj)]

Thanks for your report. However, what made you file it against the ubuntu-docs package? (It's for the user documentation of the Ubuntu desktop.)

Possibly it's not a bug at all. I'd recommend that you ask for help at <http://askubuntu.com>.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.