ImportError: Gtk3 requires X11, and no DISPLAY environment variable is set

[twisted-trac]

	@muelli reported
Trac ID	trac#9904
Type	enhancement
Created	2020-07-14 11:56:27Z

Traceback (most recent call last):
  File "/app/bin/gnome-keysign", line 10, in <module>
    sys.exit(main())
  File "/app/lib/python3.7/site-packages/keysign/__init__.py", line 22, in main
    from . import app
  File "/app/lib/python3.7/site-packages/keysign/app.py", line 31, in <module>
    from twisted.internet import gtk3reactor
  File "/app/lib/python3.7/site-packages/twisted/internet/gtk3reactor.py", line 38, in <module>
    "Gtk3 requires X11, and no DISPLAY environment variable is set")
ImportError: Gtk3 requires X11, and no DISPLAY environment variable is set

This seems to be hard coded

twisted/src/twisted/internet/gtk3reactor.py

Lines 34 to 37 in 7adb468

	if (runtime.platform.getType() == 'posix' and
	not runtime.platform.isMacOSX() and not os.environ.get("DISPLAY")):
	raise ImportError(
	"Gtk3 requires X11, and no DISPLAY environment variable is set")

clearly, people run wayland sessions.

flathub/org.gnome.Keysign#14

Searchable metadata

trac-id__9904 9904
type__enhancement enhancement
reporter__muelli muelli
priority__normal normal
milestone__None None
branch__ 
branch_author__ 
status__closed closed
resolution__fixed fixed
component__core core
keywords__None None
time__1594727787212418 1594727787212418
changetime__1599881875740526 1599881875740526
version__None None
owner__Tom_Most__twm_____ Tom Most <twm@...>

[twisted-trac]

	@muelli commented

I have just found this bug which introduced the check: #6170

[twisted-trac]

	@muelli commented

I have experimented a little bit.

My setup is a freshly installed Ubuntu 20.04 with a Wayland session.
xlsclients shows a few thing, namely:
ubuntu-Standard-PC-Q35-ICH9-2009 spice-vdagent
ubuntu-Standard-PC-Q35-ICH9-2009 gsd-xsettings
ubuntu-Standard-PC-Q35-ICH9-2009 ibus-x11
ubuntu-Standard-PC-Q35-ICH9-2009 gnome-shell

When starting a X11 application, e.g. xeyes, xlsclients shows:
ubuntu-Standard-PC-Q35-ICH9-2009 spice-vdagent
ubuntu-Standard-PC-Q35-ICH9-2009 gsd-xsettings
ubuntu-Standard-PC-Q35-ICH9-2009 ibus-x11
ubuntu-Standard-PC-Q35-ICH9-2009 gnome-shell
ubuntu-Standard-PC-Q35-ICH9-2009 xeyes

Now, I've run
$ env --unset DISPLAY gnome-keysign

to make sure that it doesn't use X.
Note that gnome-keysign makes use of the gtk3 reactor.
Of course, it crashes due to the test in /usr/lib/python3/dist-packages/twisted/internet/gtk3reactor.py.
But after I have simply patched the whole test out, it ran fine.

xlsclients does not show the additional app.

I conclude that the gtk3 reactor runs fine with the DISPLAY variable being set. And it runs fine on Wayland.

[twisted-trac]

	@muelli commented

#1379

[twisted-trac]

	@twm set owner to @twm @twm set status to assigned

[twisted-trac]

	@twm removed owner @twm set status to new

Approved: #1379 (review)

[twisted-trac]

	@twm set owner to @twm @twm set status to closed

In changeset 6546d06

#!CommitTicketReference repository="" revision="6546d06769e4ca93771608fd4cbdb81d0654aa95"
Merge pull request #1379 from muelli/9904-muelli-wayland

Author: muelli
Reviewer: twm
Fixes: ticket:9904

gtk3: remove check for DISPLAY variable