Support Flatpak and Snap Discord; keep the timer when a game changes process

Look for discord-ipc sockets in the Flatpak and Snap runtime folders too. When a game moves to another
process (e.g. at Steam launch), keep its first start time and don't resend the activity. Bump version to 0.2.

PKGBUILD

@@ -12,7 +12,7 @@ makedepends=('git')
 checkdepends=('python-pytest')
 source=("git+$url?signed#tag=$pkgver")
 validpgpkeys=('7E12BC1FF3B6EDB2CD8053EB981A2B2A3BBF5514')
-sha256sums=('SKIP')
+sha256sums=('902f970ee1521e6bb7ca5bec0eb6057f476772b08f76eb23af83ede3f5807cb3')
 
 check()
 {

README.md

@@ -1,7 +1,7 @@
 # discord-game-presence
 
 Shows the game you're playing in Discord ("Playing Genshin Impact", with the game's icon and a timer) when Discord
-can't detect it by itself, for example because Discord runs in a firejail sandbox.
+can't detect it by itself because it runs in a sandbox: Flatpak, Snap or firejail.
 
 Discord normally detects games by looking at running processes. In a sandbox with its own PID namespace it sees only
 its own processes, so it never notices a game. discord-game-presence runs outside the sandbox, watches `/proc`, and
@@ -26,8 +26,10 @@ Discord then shows it the same way as a game it detected itself.
 ## Requirements
 
 - `python` (3.11 or newer; standard library only)
-- Discord's IPC socket (`$XDG_RUNTIME_DIR/discord-ipc-0`) reachable from outside the sandbox. With firejail's
-  `discord` profile, add this to `/etc/firejail/discord.local` (the blacklists keep the keyring private):
+- Discord's IPC socket reachable from outside the sandbox. Flatpak (`$XDG_RUNTIME_DIR/app/com.discordapp.Discord/`)
+  and Snap (`$XDG_RUNTIME_DIR/snap.discord/`) sockets are found as they are. firejail's `discord` profile hides
+  `$XDG_RUNTIME_DIR/discord-ipc-0`; add this to `/etc/firejail/discord.local` (the blacklists keep the keyring
+  private):
 
   ```
   ignore include whitelist-runuser-common.inc
@@ -39,10 +41,17 @@ Discord then shows it the same way as a game it detected itself.
 
 ## Installation
 
-Build and install the package with the included PKGBUILD, then enable the user service:
+Build and install the package with the included PKGBUILD, which builds the signed release tag set in `pkgver`:
 
 ```
 makepkg -si
+```
+
+Or, with aurutils, build it into a local repository with `aur build` and install it with pacman.
+
+Then enable the user service:
+
+```
 systemctl --user enable --now discord-game-presence
 ```
 

discord_game_presence.py

@@ -16,17 +16,18 @@ import tomllib
 import urllib.request
 import uuid
 from collections.abc import Callable
-from dataclasses import dataclass, field
+from dataclasses import dataclass, field, replace
 from pathlib import Path
 from typing import Any
 
-__version__ = "0.1"
+__version__ = "0.2"
 
 NAME = "discord-game-presence"
 DETECTABLE_URL = "https://discord.com/api/v9/applications/detectable"
 CACHE_MAX_AGE = 7 * 24 * 3600  # seconds before the game list is downloaded again
 CACHE_CHECK = 3600  # seconds between cache age checks in the daemon
 CACHE_RETRY = 600  # seconds between download attempts while there is no game list at all
+SOCKET_DIRS = ("", "app/com.discordapp.Discord", "snap.discord")  # under XDG_RUNTIME_DIR: host/firejail, Flatpak, Snap
 
 OP_HANDSHAKE, OP_FRAME, OP_CLOSE, OP_PING, OP_PONG = range(5)
 
@@ -208,11 +209,11 @@ def scan(index: GameIndex, proc: Path = Path("/proc")) -> list[Game]:
 
 
 def choose(games: list[Game], current: Game | None) -> Game | None:
-    """Keep showing the current game while it runs, else the oldest one."""
+    """Keep showing the current game while it runs, timed from its first process, else the oldest one."""
     if current is not None:
         for game in games:
             if game.app.id == current.app.id:
-                return game
+                return replace(game, start=min(game.start, current.start))
     return games[0] if games else None
 
 
@@ -272,8 +273,7 @@ class DiscordIPC:
     @classmethod
     def connect(cls, client_id: str, runtime_dir: Path, timeout: float = 5.0) -> "DiscordIPC":
         error: OSError = FileNotFoundError(f"no discord-ipc socket in {runtime_dir}")
-        for i in range(10):
-            path = runtime_dir / f"discord-ipc-{i}"
+        for path in (runtime_dir / d / f"discord-ipc-{i}" for d in SOCKET_DIRS for i in range(10)):
             if not path.exists():
                 continue
             sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
@@ -363,8 +363,8 @@ class Presence:
         if game is None:
             self.failing = False
             return
-        if game == self.shown:
-            return
+        if self.shown is not None and game.start == self.shown.start:
+            return  # same app and timer: only the process changed
         try:
             if self.ipc is None:
                 self.ipc = DiscordIPC.connect(game.app.id, self.runtime_dir)
@@ -406,6 +406,8 @@ def run(config: Config, cache: Path, runtime_dir: Path, stop: threading.Event, p
                 log.info("%s exited", current.app.name)
             if game is not None and (current is None or game.app.id != current.app.id):
                 log.info("Detected %s (pid %d)", game.app.name, game.pid)
+            elif game is not None and current is not None and game.pid != current.pid:
+                log.debug("%s now pid %d", game.app.name, game.pid)
             current = game
             presence.update(game)
             stop.wait(config.interval)

tests/test_discord_game_presence.py

@@ -2,6 +2,7 @@ import json
 import os
 import socket
 import struct
+import tempfile
 import threading
 import time
 from collections.abc import Iterator
@@ -158,6 +159,9 @@ def test_choose() -> None:
     assert dgp.choose([], None) is None
     assert dgp.choose([a, b], None) == a
     assert dgp.choose([a, b], b) == b
+    # same app on a newer process: keep the first start so the timer doesn't restart
+    moved = dgp.Game(dgp.App("2", "B"), 3, 205)
+    assert dgp.choose([a, moved], b) == dgp.Game(dgp.App("2", "B"), 3, 200)
     assert dgp.choose([a], b) == a
 
 
@@ -291,9 +295,10 @@ class FakeDiscord:
 
 
 @pytest.fixture
-def runtime_dir(tmp_path: Path) -> Iterator[Path]:
-    # AF_UNIX paths are limited to ~108 bytes, so don't nest deeply
-    yield tmp_path
+def runtime_dir() -> Iterator[Path]:
+    # AF_UNIX paths are limited to 107 bytes: tmp_path plus the Flatpak subdir can exceed it
+    with tempfile.TemporaryDirectory(prefix="dgp-", dir="/tmp") as d:
+        yield Path(d)
 
 
 def test_ipc_set_activity(runtime_dir: Path) -> None:
@@ -316,6 +321,15 @@ def test_ipc_later_socket(runtime_dir: Path) -> None:
     dgp.DiscordIPC.connect("123", runtime_dir).close()
 
 
+@pytest.mark.parametrize("subdir", ["app/com.discordapp.Discord", "snap.discord"])
+def test_ipc_sandbox_socket(runtime_dir: Path, subdir: str) -> None:
+    (runtime_dir / subdir).mkdir(parents=True)
+    discord = FakeDiscord(runtime_dir / subdir / "discord-ipc-0")
+    dgp.DiscordIPC.connect("123", runtime_dir).close()
+    assert discord.received[0] == (dgp.OP_HANDSHAKE, {"v": 1, "client_id": "123"})
+    discord.stop()
+
+
 def test_ipc_no_socket(runtime_dir: Path) -> None:
     with pytest.raises(FileNotFoundError):
         dgp.DiscordIPC.connect("123", runtime_dir)
@@ -352,6 +366,7 @@ def test_presence(runtime_dir: Path) -> None:
     presence.update(genshin)
     assert presence.shown == genshin
     presence.update(genshin)  # unchanged: nothing sent
+    presence.update(dgp.Game(genshin.app, 11, 100))  # another process, same timer: nothing sent
     assert len(discord.received) == 2
 
     presence.update(neverwinter)  # another app needs a new connection