How to provide Wayland socket to docker container

How to provide Wayland socket to docker container

To run Wayland applications in docker, you need an already running Wayland compositor like Gnome-Wayland or Weston.

• Wayland compositors normally provide an X display with Xwayland, too. You can share access to Xwayland the same way as access to regular Xorg.
• You have to share the Wayland socket. You find it in XDG_RUNTIME_DIR and its name is stored in environment variable WAYLAND_DISPLAY.
• XDG_RUNTIME_DIR only allows access for its owner, so you need the same user in container as on host.
• Example similar to x11docker option --hostwayland:

docker run -e XDG_RUNTIME_DIR=/tmp \
           -e WAYLAND_DISPLAY=$WAYLAND_DISPLAY \
           -v $XDG_RUNTIME_DIR/$WAYLAND_DISPLAY:/tmp/$WAYLAND_DISPLAY  \
           --user=$(id -u):$(id -g) \
           imagename waylandapplication

• QT5 applications also need -e QT_QPA_PLATFORM=wayland and must be started with imagename dbus-launch waylandapplication.
• You can combine Wayland access and X access to provide both to docker container.
  • You can indicate that you prefer Wayland with -e XDG_SESSION_TYPE=wayland
• Collection of Wayland related environment variables for different toolkits:
  • GTK: GDK_BACKEND=wayland
  • QT5: QT_QPA_PLATFORM=wayland
  • Clutter/GTK3: CLUTTER_BACKEND=wayland
  • SDL: SDL_VIDEODRIVER=wayland
  • E / Enlightenment: ELM_DISPLAY=wl ELM_ACCEL=opengl ECORE_EVAS_ENGINE=wayland_egl