[Waybar] Add custom update manager

.config/waybar/config

@@ -1,7 +1,7 @@
 [{
     "spacing": 4, // Gaps between modules (4px)
     "modules-left": ["sway/workspaces", "sway/mode", "custom/media"],
-    "modules-right": ["pulseaudio", "memory", "cpu", "battery", "network", "clock", "tray"],
+    "modules-right": ["pulseaudio", "memory", "cpu", "battery", "network", "custom/pacman", "clock", "tray"],
     "memory": {
         "format": "\uf538 {used:0.1f}GiB",
     },
@@ -55,6 +55,17 @@
             "default": ["", "", ""]
         },
         "on-click": "pavucontrol"
+    },
+    "custom/pacman": {
+        "format": "{icon} {}",
+        "return-type": "json",
+        "escape": true,
+        "format-icons": {
+            "uptodate": "\uf00c",
+            "available": "\uf019"
+        },
+        "interval": 600,
+        "exec": "$HOME/.config/waybar/pacman.py '(?:^(?:linux-|sway|wl)|pipewire)' 2> /dev/null"
     }
 }]
 

.config/waybar/pacman.py

@@ -0,0 +1,85 @@
+#!/usr/bin/env python3
+
+import json
+import os
+import re
+import subprocess
+import sys
+
+
+PACMAN_UPDATES_DB = f'/tmp/checkup-db-{os.getlogin()}/'
+
+
+def write_output(packages, important_regex):
+    n_packages = packages.count('\n')
+    if n_packages == 0:
+        output_text = 'Up to date'
+        output_class = 'good'
+        output_alt = 'uptodate'
+    else:
+        if n_packages == 1:
+            output_text = '1 update available'
+        else:
+            output_text = f'{n_packages} updates available'
+        output_class = 'info'
+        output_alt = 'available'
+
+    if important_regex and re.search(important_regex, packages,
+                                     flags=re.MULTILINE):
+        output_class = 'important'
+
+    output = {'text': output_text,
+              'class': output_class,
+              'alt': output_alt}
+
+    sys.stdout.write(json.dumps(output) + '\n')
+    sys.stdout.flush()
+
+
+def generate_and_update_database():
+    if not os.path.isdir(PACMAN_UPDATES_DB):
+        os.mkdir(PACMAN_UPDATES_DB)
+
+    subprocess.run(['fakeroot',
+                    '--',
+                    'pacman',
+                    '-Sy',
+                    '--dbpath',
+                    PACMAN_UPDATES_DB,
+                    '--logfile',
+                    '/dev/null'],
+                   env={'LC_ALL': 'C'},
+                   stdout=subprocess.DEVNULL,
+                   stderr=subprocess.STDOUT)
+
+
+def check_updates(important_regex):
+    p = subprocess.run(['fakeroot',
+                        '--',
+                        'pacman',
+                        '-Qu',
+                        '--dbpath',
+                        PACMAN_UPDATES_DB],
+                       env={'LC_ALL': 'C'},
+                       capture_output=True)
+    packages = p.stdout.decode('utf-8')
+
+    p = subprocess.run(['yay',
+                        '-Qua',
+                        '--devel'],
+                       capture_output=True)
+    packages += p.stdout.decode('utf-8')
+
+    write_output(packages, important_regex)
+
+
+def main(important_regex=None):
+    generate_and_update_database()
+    check_updates(important_regex)
+
+
+if __name__ == '__main__':
+    if len(sys.argv) > 1:
+        main(sys.argv[1])
+    else:
+        main()

.config/waybar/style.css

@@ -136,6 +136,26 @@ label:focus {
     color: #002b36;
 }
 
+#custom-pacman {
+    padding-left: 5px;
+    padding-right: 5px;
+}
+
+#custom-pacman.good {
+    background-color: #859900;
+    color: #002b36;
+}
+
+#custom-pacman.info {
+    background-color: #268bd2;
+    color: #002b36;
+}
+
+#custom-pacman.important {
+    background-color: #d30102;
+    color: #002b36;
+}
+
 #custom-media {
     background-color: #66cc99;
     color: #2a5c45;