A new kitten to draw dock panels on X11 desktops showing the output from running arbitrary terminal programs

docs/index.rst

@@ -239,6 +239,10 @@ Some prominent kittens:
     filenames, words, lines, etc from the terminal screen.
 
 
+:doc:`Panel <kittens/panel>`
+    Draw a GPU accelerated dock panel on your desktop showing the output
+    from an arbitrary terminal program.
+
 .. _sessions:
 
 Startup Sessions

docs/kittens/panel.rst

@@ -0,0 +1,37 @@
+Draw a GPU accelerated dock panel on your desktop
+====================================================================================================
+
+.. highlight:: sh
+
+
+You can use this kitten to draw a GPU accelerated panel on the edge
+of your screen, that shows the output from an arbitrary terminal program.
+
+It is useful for showing status information or notifications on your desktop
+using terminal programs instead of GUI toolkits.
+
+
+.. figure:: ../screenshots/panel.png
+   :alt: Screenshot, showing a sample panel
+   :align: center
+   :scale: 100%
+
+   Screenshot, showing a sample panel
+
+
+The screenshot above shows a sample panel that displays the current desktop and
+window title as well as miscellaneous system information such as network
+activity, CPU load, date/time, etc.
+
+.. note::
+
+    This kitten currently only works on X11 desktops
+
+Using this kitten is simple, for example::
+
+    kitty +kitten panel sh -c 'printf "\n\n\nHello, world."; sleep 5s'
+
+This will show ``Hello, world.`` at the top edge of your screen for five
+seconds. Here the terminal program we are running is ``sh`` with a script to
+print out ``Hello, world!``. You can make the terminal program as complex as
+you like, as demonstrated in the screenshot above.

kittens/panel/main.py

@@ -0,0 +1,143 @@
+#!/usr/bin/env python
+# vim:fileencoding=utf-8
+# License: GPL v3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
+
+import subprocess
+import sys
+
+from kitty.constants import is_macos, is_wayland
+from kitty.cli import parse_args
+
+
+OPTIONS = r'''
+--lines
+type=int
+default=1
+The number of lines shown in the panel (the height of the panel). Applies to horizontal panels.
+
+
+--columns
+type=int
+default=20
+The number of columns shown in the panel (the width of the panel). Applies to vertical panels.
+
+
+--edge
+choices=top,bottom,left,right
+default=top
+Which edge of the screen to place the panel on. Note that some window managers
+(such as i3) do not support placing docked windows on the left and right edges.
+
+
+--config -c
+type=list
+Path to config file to use for kitty when drawing the panel.
+
+
+--override -o
+type=list
+Override individual kitty configuration options, can be specified multiple times.
+Syntax: :italic:`name=value`. For example: :option:`kitty +kitten panel -o` font_size=20
+'''.format
+
+
+args = None
+
+
+def parse_panel_args(args):
+    msg = 'Use a command line program to draw a GPU accelerated panel on your X11 desktop'
+    return parse_args(args, OPTIONS, 'program-to-run', msg, 'panel')
+
+
+def call_xprop(*cmd, silent=False):
+    cmd = ['xprop'] + list(cmd)
+    try:
+        cp = subprocess.run(cmd, stdout=subprocess.DEVNULL if silent else None)
+    except FileNotFoundError:
+        raise SystemExit('You must have the xprop program installed')
+    if cp.returncode != 0:
+        raise SystemExit(cp.returncode)
+
+
+def create_strut(
+    win_id,
+    left=0, right=0, top=0, bottom=0, left_start_y=0, left_end_y=0,
+    right_start_y=0, right_end_y=0, top_start_x=0, top_end_x=0,
+    bottom_start_x=0, bottom_end_x=0
+):
+    call_xprop(
+            '-id',
+            str(int(win_id)), '-format', '_NET_WM_STRUT_PARTIAL', '32cccccccccccc',
+            '-set', '_NET_WM_STRUT_PARTIAL',
+            '{left},{right},{top},{bottom},'
+            '{left_start_y},{left_end_y},{right_start_y},{right_end_y},'
+            '{top_start_x},{top_end_x},{bottom_start_x},{bottom_end_x}'.format(**locals())
+    )
+
+
+def create_top_strut(win_id, width, height):
+    create_strut(win_id, top=height, top_end_x=width)
+
+
+def create_bottom_strut(win_id, width, height):
+    create_strut(win_id, bottom=height, bottom_end_x=width)
+
+
+def create_left_strut(win_id, width, height):
+    create_strut(win_id, left=width, left_end_y=height)
+
+
+def create_right_strut(win_id, width, height):
+    create_strut(win_id, right=width, right_end_y=height)
+
+
+def setup_x11_window(win_id):
+    call_xprop(
+            '-id', str(win_id), '-format', '_NET_WM_WINDOW_TYPE', '32a',
+            '-set', '_NET_WM_WINDOW_TYPE', '_NET_WM_WINDOW_TYPE_DOCK'
+    )
+    func = globals()['create_{}_strut'.format(args.edge)]
+    func(win_id, initial_window_size_func.width, initial_window_size_func.height)
+
+
+def initial_window_size_func(opts, *a):
+    from kitty.fast_data_types import glfw_primary_monitor_size, set_smallest_allowed_resize
+
+    def initial_window_size(cell_width, cell_height, dpi_x, dpi_y):
+        monitor_width, monitor_height = glfw_primary_monitor_size()
+        if args.edge in {'top', 'bottom'}:
+            h = initial_window_size_func.height = cell_height * args.lines + 1
+            initial_window_size_func.width = monitor_width
+            set_smallest_allowed_resize(100, h)
+        else:
+            w = initial_window_size_func.width = cell_width * args.columns + 1
+            initial_window_size_func.height = monitor_height
+            set_smallest_allowed_resize(w, 100)
+        return initial_window_size_func.width, initial_window_size_func.height
+
+    return initial_window_size
+
+
+def main(sys_args):
+    global args
+    if is_macos or is_wayland:
+        raise SystemExit('Currently the panel kitten is supported only on X11 desktops')
+    call_xprop('-version', silent=True)  # ensure xprop is available
+    args, items = parse_panel_args(sys_args[1:])
+    if not items:
+        raise SystemExit('You must specify the program to run')
+    sys.argv = ['kitty']
+    if args.config:
+        sys.argv.append('--config={}'.format(args.config))
+    for override in args.override:
+        sys.argv.append('--override={}'.format(override))
+    sys.argv.extend(items)
+    from kitty.main import run_app, main
+    run_app.cached_values_name = 'panel'
+    run_app.first_window_callback = setup_x11_window
+    run_app.initial_window_size_func = initial_window_size_func
+    main()
+
+
+if __name__ == '__main__':
+    main(sys.argv)

kittens/runner.py

@@ -12,7 +12,7 @@ aliases = {'url_hints': 'hints'}
 
 
 def resolved_kitten(k):
-    return aliases.get(k, k)
+    return aliases.get(k, k).replace('-', '_')
 
 
 def import_kitten_main_module(config_dir, kitten):