keyd-application-mapper: Add Gnome 45 support (#639, #649)

Add support for Gnome 45, which breaks backward extension
compatibility. We now ship and maintain two extensions :/.

The main change in Gnome seems to be the switch from a custom
import implementation to 'standard' ES6 style imports.
The init method also seems to have inexplicably
been swapped out in favour of extending a magic
class.

This patch takes the opportunity to clean up some residual cruft
and move the extension code out of the mapper script.

Specifically:

 - Ship distinct extensions for Gnome 42-44 and Gnome 45 in /usr/local/share/keyd
 - Move the named pipe to XDG_RUNTIME_DIR
 - Initialize the pipe inside the extension instead of the script
   to avoid potential race conditions during initialization.

Makefile

@@ -73,6 +73,7 @@ install:
 	install -m644 docs/*.md $(DESTDIR)$(PREFIX)/share/doc/keyd/
 	install -m644 examples/* $(DESTDIR)$(PREFIX)/share/doc/keyd/examples/
 	install -m644 layouts/* $(DESTDIR)$(PREFIX)/share/keyd/layouts
+	cp -r data/gnome-* $(DESTDIR)$(PREFIX)/share/keyd
 	install -m644 data/*.1.gz $(DESTDIR)$(PREFIX)/share/man/man1/
 	install -m644 data/keyd.compose $(DESTDIR)$(PREFIX)/share/keyd/
 

data/gnome-extension-45/extension.js

@@ -0,0 +1,65 @@
+import * as Main from 'resource:///org/gnome/shell/ui/main.js';
+import GLib from 'gi://GLib';
+import Shell from 'gi://Shell';
+import Gio from 'gi://Gio';
+import { Extension } from 'resource:///org/gnome/shell/extensions/extension.js';
+
+let file = Gio.File.new_for_path(makePipe());
+let pipe = file.append_to_async(0, 0, null, on_pipe_open);
+
+function makePipe() {
+	let runtime_dir = GLib.getenv('XDG_RUNTIME_DIR');
+	if (!runtime_dir)
+		runtime_dir = '/run/user/'+new TextDecoder().decode(
+			GLib.spawn_command_line_sync('id -u')[1]
+		).trim();
+
+	let path = runtime_dir + '/keyd.fifo';
+	GLib.spawn_command_line_sync('mkfifo ' + path);
+
+	return path;
+}
+
+function send(msg) {
+	if (!pipe)
+		return;
+
+	try {
+		pipe.write(msg, null);
+	} catch {
+		log('pipe closed, reopening...');
+		pipe = null;
+		file.append_to_async(0, 0, null, on_pipe_open);
+	}
+}
+
+function on_pipe_open(file, res) {
+	log('pipe opened');
+	pipe = file.append_to_finish(res);
+}
+
+export default class KeydExtension extends Extension {
+	enable() {
+		Shell.WindowTracker.get_default().connect('notify::focus-app', () => {
+			const win = global.display.focus_window;
+			const cls = win ? win.get_wm_class() : 'root';
+			const title = win ? win.get_title() : '';
+
+			send(`${cls}	${title}\n`);
+		});
+
+		Main.layoutManager.connectObject(
+			'system-modal-opened', () => {
+				send(`system-modal	${global.stage.get_title()}\n`);
+			},
+			this
+		);
+
+		 GLib.spawn_command_line_async('keyd-application-mapper -d'); 
+	}
+
+	disable() {
+		GLib.spawn_command_line_async('pkill -f keyd-application-mapper');
+	}
+}
+

data/gnome-extension-45/metadata.json

@@ -0,0 +1,7 @@
+{
+	"name": "keyd",
+	"description": "Used by keyd to obtain active window information.",
+	"uuid": "keyd",
+	"shell-version": [ "45" ]
+}
+

data/gnome-extension/extension.js

@@ -0,0 +1,65 @@
+const Shell = imports.gi.Shell;
+const GLib = imports.gi.GLib;
+const Gio = imports.gi.Gio;
+const Main = imports.ui.main;
+
+let file = Gio.File.new_for_path(makePipe());
+let pipe = file.append_to_async(0, 0, null, on_pipe_open);
+
+function makePipe() {
+	let runtime_dir = GLib.getenv('XDG_RUNTIME_DIR');
+	if (!runtime_dir)
+		runtime_dir = '/run/user/'+new TextDecoder().decode(
+			GLib.spawn_command_line_sync('id -u')[1]
+		).trim();
+
+	let path = runtime_dir + '/keyd.fifo';
+	GLib.spawn_command_line_sync('mkfifo ' + path);
+
+	return path;
+}
+
+function send(msg) {
+	if (!pipe)
+		return;
+
+	try {
+		pipe.write(msg, null);
+	} catch {
+		log('pipe closed, reopening...');
+		pipe = null;
+		file.append_to_async(0, 0, null, on_pipe_open);
+	}
+}
+
+function on_pipe_open(file, res) {
+	log('pipe opened');
+	pipe = file.append_to_finish(res);
+}
+
+function init() {
+	return {
+		enable: function() {
+			Shell.WindowTracker.get_default().connect('notify::focus-app', () => {
+				const win = global.display.focus_window;
+				const cls = win ? win.get_wm_class() : 'root';
+				const title = win ? win.get_title() : '';
+
+				send(`${cls}	${title}\n`);
+			});
+
+			Main.layoutManager.connectObject(
+				'system-modal-opened', () => {
+					send(`system-modal	${global.stage.get_title()}\n`);
+				},
+				this
+			);
+
+			 GLib.spawn_command_line_async('keyd-application-mapper -d'); 
+		},
+
+		disable: function() {
+			GLib.spawn_command_line_async('pkill -f keyd-application-mapper');
+		}
+	}
+}

data/gnome-extension/metadata.json

@@ -0,0 +1,7 @@
+{
+	"name": "keyd",
+	"description": "Used by keyd to obtain active window information.",
+	"uuid": "keyd",
+	"shell-version": [ "42", "43", "44" ]
+}
+

scripts/keyd-application-mapper

@@ -6,6 +6,7 @@ import select
 import socket
 import struct
 import os
+import errno
 import shutil
 import re
 import sys
@@ -294,97 +295,37 @@ class GnomeMonitor():
 
         self.on_window_change = on_window_change
 
-        self.version = '1.4'
-        self.extension_dir = os.getenv('HOME') + '/.local/share/gnome-shell/extensions/keyd'
-        self.fifo_path = self.extension_dir + '/keyd.fifo'
-
-    def _install(self):
-        shutil.rmtree(self.extension_dir, ignore_errors=True)
-        os.makedirs(self.extension_dir, exist_ok=True)
-
-        extension = '''
-        const Shell = imports.gi.Shell;
-        const GLib = imports.gi.GLib;
-        const Main = imports.ui.main;
-
-        // We have to keep an explicit reference around to prevent garbage collection :/.
-        let file = imports.gi.Gio.File.new_for_path('%s');
-        let pipe = file.append_to_async(0, 0, null, on_pipe_open);
-
-        function send(msg) {
-            if (!pipe)
-                return;
-
-            try {
-                pipe.write(msg, null);
-            } catch {
-                log('pipe closed, reopening...');
-                pipe = null;
-                file.append_to_async(0, 0, null, on_pipe_open);
-            }
-        }
-
-        function on_pipe_open(file, res) {
-            log('pipe opened');
-            pipe = file.append_to_finish(res);
-        }
-
-        function init() {
-                Shell.WindowTracker.get_default().connect('notify::focus-app', () => {
-                    const win = global.display.focus_window;
-                    const cls = win ? win.get_wm_class() : 'root';
-                    const title = win ? win.get_title() : '';
-
-                    send(`${cls}\\t${title}\\n`);
-                });
-
-                Main.layoutManager.connectObject(
-                    'system-modal-opened', () => {
-                        send(`system-modal\\t${global.stage.get_title()}\\n`);
-                    },
-                    this
-                );
-
-                return {
-                    enable: ()=>{ GLib.spawn_command_line_async('keyd-application-mapper -d'); },
-                    disable: ()=>{ GLib.spawn_command_line_async('pkill -f keyd-application-mapper'); }
-                };
-
-        }
-        ''' % (self.fifo_path)
-
-        metadata = '''
-        {
-                "name": "keyd",
-                "description": "Used by keyd to obtain active window information.",
-                "uuid": "keyd",
-                "shell-version": [ "41", "42", "43" ]
-        }
-        '''
-
-        open(self.extension_dir + '/version', 'w').write(self.version)
-        open(self.extension_dir + '/metadata.json', 'w').write(metadata)
-        open(self.extension_dir + '/extension.js', 'w').write(extension)
-        os.mkfifo(self.fifo_path)
-
-    def _is_installed(self):
-        try:
-            return open(self.extension_dir + '/version', 'r').read() == self.version
-        except:
-            return False
+        self.fifo_path = (os.getenv('XDG_RUNTIME_DIR') or '/run/user/'+str(os.getuid())) + '/keyd.fifo'
 
     def init(self):
-        if not self._is_installed():
-            print('keyd extension not found, installing...')
-            self._install()
-            run_or_die('gsettings set org.gnome.shell disable-user-extensions false');
+        if not os.path.exists(self.fifo_path):
+            print("""Gnome extension doesn't appear to be running:
 
-            print('Success! Please restart Gnome and run this script one more time.')
-            exit(0)
+You will need to install the keyd gnome extension in order for the
+application mapper to work correctly.
+
+This can usually be achieved by running:
+
+rm -r ~/.local/share/gnome-shell/extensions/keyd # Remove any older versions of the extension
+mkdir -p ~/.local/share/gnome-shell/extensions
+
+Followed by:
 
-        if 'DISABLED' in run('gnome-extensions show keyd'):
-            run_or_die('gnome-extensions enable keyd', 'Failed to enable keyd extension.')
-            print(f'Successfully enabled keyd extension :). Output will be stored in {LOGFILE}')
+Gnome 42-44:
+    ln -s /usr/local/share/keyd/gnome-extension ~/.local/share/gnome-shell/extensions/keyd
+
+Gnome 45:
+    ln -s /usr/local/share/keyd/gnome-extension-45 ~/.local/share/gnome-shell/extensions/keyd
+
+Finally restart Gnome and run:
+
+            gnome-extensions enable keyd
+            gnome-extensions show keyd (verify the extension is enabled)
+
+NOTE:
+    You may need to adjust the above paths (e.g /usr/share/keyd/gnome-extension)
+    depending on your distro.
+""")
             exit(0)
 
     def run(self):
@@ -397,9 +338,13 @@ class GnomeMonitor():
                 self.on_window_change(last_cls, last_title)
                 continue
 
-            (cls, title) = line.strip('\n').split('\t')
-            last_cls = cls
-            last_title = title
+            try:
+                (cls, title) = line.strip('\n').split('\t')
+                last_cls = cls
+                last_title = title
+            except:
+                cls = ''
+                title = ''
 
             self.on_window_change(cls, title)