bug: ActivityWatch watchers always crash after startup

[ondt]

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• My Nixpkgs and Home Manager versions are in sync

Is there an existing issue for this?

• I have searched the existing issues

Issue description

Both aw-watcher-afk and aw-watcher-window are crashing on startup:

-- Boot d98014b0da0a4689aa35788c5e380235 --
říj 14 21:51:52 desktop systemd[2894]: Started ActivityWatch watcher 'aw-watcher-window'.
říj 14 21:51:53 desktop aw-watcher-window[2978]: Traceback (most recent call last):
říj 14 21:51:53 desktop aw-watcher-window[2978]:   File "/nix/store/69g5zb7z36cf04lazngghn4qykh2faz7-aw-watcher-window-0.12.2/bin/.aw-watcher-window-wrapped", line 9, in <module>
říj 14 21:51:53 desktop aw-watcher-window[2978]:     sys.exit(main())
říj 14 21:51:53 desktop aw-watcher-window[2978]:              ^^^^^^
říj 14 21:51:53 desktop aw-watcher-window[2978]:   File "/nix/store/69g5zb7z36cf04lazngghn4qykh2faz7-aw-watcher-window-0.12.2/lib/python3.12/site-packages/aw_watcher_window/main.py", line 40, in main
říj 14 21:51:53 desktop aw-watcher-window[2978]:     raise Exception("DISPLAY environment variable not set")
říj 14 21:51:53 desktop aw-watcher-window[2978]: Exception: DISPLAY environment variable not set
říj 14 21:51:53 desktop systemd[2894]: activitywatch-watcher-aw-watcher-window.service: Main process exited, code=exited, status=1/FAILURE
říj 14 21:51:53 desktop systemd[2894]: activitywatch-watcher-aw-watcher-window.service: Failed with result 'exit-code'.

When I start them manually using systemctl --user restart activitywatch-watcher-aw-watcher-afk.service activitywatch-watcher-aw-watcher-window.service or systemctl --user restart activitywatch.target, they crash again when the system is shutting down:

říj 15 16:32:46 desktop systemd[2894]: Started ActivityWatch watcher 'aw-watcher-window'.
říj 15 16:32:46 desktop aw-watcher-window[474433]: 2024-10-15 16:32:46 [INFO ]: aw-watcher-window started  (aw_watcher_window.main:62)
říj 15 16:32:47 desktop aw-watcher-window[474433]: 2024-10-15 16:32:47 [INFO ]: Connection to aw-server established by aw-watcher-window  (aw_client.client:447)
říj 20 20:01:34 desktop aw-watcher-window[474433]: 2024-10-20 20:01:34 [WARNING]: X server closed connection, exiting  (aw_watcher_window.xlib:52)
říj 20 20:01:34 desktop aw-watcher-window[474433]: 2024-10-20 20:01:34 [ERROR]: Fatal error, stopping  (aw_watcher_window.main:111)
říj 20 20:01:34 desktop aw-watcher-window[474433]: Traceback (most recent call last):
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/hlzfdwqhmglqxx9bdbm6b3g89bpx9qdk-python3.12-xlib-0.33/lib/python3.12/site-packages/Xlib/protocol/display.py", line 583, in send_and_recv
říj 20 20:01:34 desktop aw-watcher-window[474433]:     i = self.socket.send(self.data_send)
říj 20 20:01:34 desktop aw-watcher-window[474433]:         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
říj 20 20:01:34 desktop aw-watcher-window[474433]: BrokenPipeError: [Errno 32] Broken pipe
říj 20 20:01:34 desktop aw-watcher-window[474433]: During handling of the above exception, another exception occurred:
říj 20 20:01:34 desktop aw-watcher-window[474433]: Traceback (most recent call last):
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/69g5zb7z36cf04lazngghn4qykh2faz7-aw-watcher-window-0.12.2/lib/python3.12/site-packages/aw_watcher_window/xlib.py", line 43, in get_current_window
říj 20 20:01:34 desktop aw-watcher-window[474433]:     window_id = _get_current_window_id()
říj 20 20:01:34 desktop aw-watcher-window[474433]:                 ^^^^^^^^^^^^^^^^^^^^^^^^
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/69g5zb7z36cf04lazngghn4qykh2faz7-aw-watcher-window-0.12.2/lib/python3.12/site-packages/aw_watcher_window/xlib.py", line 22, in _get_current_window_id
říj 20 20:01:34 desktop aw-watcher-window[474433]:     window_prop = screen.root.get_full_property(atom, X.AnyPropertyType)
říj 20 20:01:34 desktop aw-watcher-window[474433]:                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/hlzfdwqhmglqxx9bdbm6b3g89bpx9qdk-python3.12-xlib-0.33/lib/python3.12/site-packages/Xlib/xobject/drawable.py", line 472, in get_full_property
říj 20 20:01:34 desktop aw-watcher-window[474433]:     prop = self.get_property(property, property_type, 0, sizehint)
říj 20 20:01:34 desktop aw-watcher-window[474433]:            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/hlzfdwqhmglqxx9bdbm6b3g89bpx9qdk-python3.12-xlib-0.33/lib/python3.12/site-packages/Xlib/xobject/drawable.py", line 455, in get_property
říj 20 20:01:34 desktop aw-watcher-window[474433]:     r = request.GetProperty(display = self.display,
říj 20 20:01:34 desktop aw-watcher-window[474433]:         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/hlzfdwqhmglqxx9bdbm6b3g89bpx9qdk-python3.12-xlib-0.33/lib/python3.12/site-packages/Xlib/protocol/rq.py", line 1368, in __init__
říj 20 20:01:34 desktop aw-watcher-window[474433]:     self.reply()
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/hlzfdwqhmglqxx9bdbm6b3g89bpx9qdk-python3.12-xlib-0.33/lib/python3.12/site-packages/Xlib/protocol/rq.py", line 1380, in reply
říj 20 20:01:34 desktop aw-watcher-window[474433]:     self._display.send_and_recv(request = self._serial)
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/hlzfdwqhmglqxx9bdbm6b3g89bpx9qdk-python3.12-xlib-0.33/lib/python3.12/site-packages/Xlib/protocol/display.py", line 586, in send_and_recv
říj 20 20:01:34 desktop aw-watcher-window[474433]:     raise self.socket_error
říj 20 20:01:34 desktop aw-watcher-window[474433]: Xlib.error.ConnectionClosedError: Display connection closed by server: [Errno 32] Broken pipe
říj 20 20:01:34 desktop aw-watcher-window[474433]: During handling of the above exception, another exception occurred:
říj 20 20:01:34 desktop aw-watcher-window[474433]: Traceback (most recent call last):
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/69g5zb7z36cf04lazngghn4qykh2faz7-aw-watcher-window-0.12.2/lib/python3.12/site-packages/aw_watcher_window/main.py", line 106, in heartbeat_loop
říj 20 20:01:34 desktop aw-watcher-window[474433]:     current_window = get_current_window(strategy)
říj 20 20:01:34 desktop aw-watcher-window[474433]:                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/69g5zb7z36cf04lazngghn4qykh2faz7-aw-watcher-window-0.12.2/lib/python3.12/site-packages/aw_watcher_window/lib.py", line 59, in get_current_window
říj 20 20:01:34 desktop aw-watcher-window[474433]:     return get_current_window_linux()
říj 20 20:01:34 desktop aw-watcher-window[474433]:            ^^^^^^^^^^^^^^^^^^^^^^^^^^
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/69g5zb7z36cf04lazngghn4qykh2faz7-aw-watcher-window-0.12.2/lib/python3.12/site-packages/aw_watcher_window/lib.py", line 10, in get_current_window_linux
říj 20 20:01:34 desktop aw-watcher-window[474433]:     window = xlib.get_current_window()
říj 20 20:01:34 desktop aw-watcher-window[474433]:              ^^^^^^^^^^^^^^^^^^^^^^^^^
říj 20 20:01:34 desktop aw-watcher-window[474433]:   File "/nix/store/69g5zb7z36cf04lazngghn4qykh2faz7-aw-watcher-window-0.12.2/lib/python3.12/site-packages/aw_watcher_window/xlib.py", line 55, in get_current_window
říj 20 20:01:34 desktop aw-watcher-window[474433]:     raise FatalError()
říj 20 20:01:34 desktop aw-watcher-window[474433]: aw_watcher_window.exceptions.FatalError
říj 20 20:01:34 desktop systemd[2894]: activitywatch-watcher-aw-watcher-window.service: Consumed 15min 27.513s CPU time, 35.1M memory peak, 0B memory swap peak.
-- Boot 07ade846107241ec9f670f1a4d469fdf --

It seems like the watchers are started before Xorg is started, and when shutting down they aren't stopped before Xorg is stopped.

This is my ActivityWatch config:

  services.activitywatch = {
    enable = true;
    package = pkgs.aw-server-rust;
    watchers = {
      aw-watcher-afk.package = pkgs.aw-watcher-afk;
      aw-watcher-window.package = pkgs.aw-watcher-window;
    };
  };

Workaround

The problem can be fixed by adding the following snippet to the home-manager config:

  systemd.user.targets.activitywatch = {
    Unit.After = lib.mkForce [ "graphical-session.target" ];
    Install.WantedBy = lib.mkForce [ "graphical-session.target" ];
  };

Note that this workaround is not ideal because activitywatch.target itself shouldn't really need a GUI. I'm not sure if there is a way to tell whether an arbitrary watcher needs to be started after graphical-session.target or not.

Maintainer CC

@foo-dogsquared

System information

 - system: `"x86_64-linux"`
 - host os: `Linux 6.11.4, NixOS, 24.05 (Uakari), 24.05.20241019.a9b86fc`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.18.8`
 - channels(root): `""`
 - nixpkgs: `/nix/store/lbqj1cndic4121whnx8xm0jgb1c8x4xx-source`