max / alloy

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1	#!/bin/sh
2	# alloy-open — open a link, or say why it cannot.
3	#
4	# Alloy may ship without a browser. `BROWSER=none` is a supported build value
5	# and under [[alloy-byo-principle]] it may become the default, so "no browser
6	# installed" is a state the system has to handle rather than an error state.
7	# Measured on 2026-08-17, before this existed, that state looked like:
8	#
9	# $ xdg-open https://example.com ; echo $?
10	# /usr/sbin/xdg-open: line 1045: www-browser: command not found
11	# ...five more of those...
12	# xdg-open: no method available for opening 'https://example.com'
13	# 3
14	#
15	# All of it on stderr. Invoked from yazi's Open bind, from a mako action, or
16	# from a click in shop, the person sees NOTHING. That is the silent-failure
17	# class this repo hunts, and it is the reason this script exists: for the
18	# message far more than for the launching, the same way alloy-shot exists for
19	# the notification more than for the capture.
20	#
21	# Registered as the system default for http, https and text/html in
22	# /etc/xdg/mimeapps.list. That is the sysadmin level, which sits ABOVE the
23	# vendor file and BELOW the user's own, so `xdg-settings set
24	# default-web-browser` still wins and a person who has chosen a browser never
25	# comes through here again.
26	#
27	# Testing this in a container will make it look broken, and it is not. xdg-open
28	# consults the scheme-handler registration only inside `if has_display`
29	# (open_generic, /usr/sbin/xdg-open), so with no WAYLAND_DISPLAY or DISPLAY it
30	# skips straight to its hardcoded list of text browsers and prints the wall of
31	# "command not found" this script exists to prevent. Set WAYLAND_DISPLAY to
32	# test it, or read the wrong conclusion.
33	#
34	# It also fixes a smaller thing that worked by luck. The vendor mimeapps.list
35	# ships from shared-mime-info and names `org.mozilla.firefox.desktop`, which
36	# this image does not contain under any BROWSER value: Fedora's Firefox rpm is
37	# firefox.desktop, while that id belongs to the Flatpak. It resolved correctly
38	# anyway, by falling through to mimeinfo.cache where exactly one candidate
39	# declared the scheme. One browser is not a thing to rely on: a `BROWSER=none`
40	# image has none, and a user's own Flatpak is a second.
41
42	set -eu
43
44	self=alloy-open.desktop
45
46	# The same directory list alloy-menu uses, and for the same reason: a browser
47	# the user installed as a Flatpak exports its desktop entry into the flatpak
48	# tree, not into /usr/share/applications. Looking only at the latter would
49	# make BYO-via-Flatpak invisible to the thing whose whole job is to find it.
50	dirs="/usr/share/applications
51	${XDG_DATA_HOME:-$HOME/.local/share}/applications
52	/var/lib/flatpak/exports/share/applications
53	${XDG_DATA_HOME:-$HOME/.local/share}/flatpak/exports/share/applications"
54
55	# Find a desktop entry that claims https, skipping this one.
56	#
57	# Excluding self is not defensive tidiness: without it this script is the
58	# handler that finds itself and execs itself, which is an unkillable loop
59	# behind a keybind. Matched on the filename rather than on Exec= because the
60	# filename is what the mimeapps entry names.
61	browser_entry() {
62	printf '%s\n' "$dirs" \| while IFS= read -r dir; do
63	[ -d "$dir" ] \|\| continue
64	for f in "$dir"/*.desktop; do
65	[ -f "$f" ] \|\| continue
66	[ "${f##*/}" = "$self" ] && continue
67	grep -q '^MimeType=.*x-scheme-handler/https' "$f" \|\| continue
68	grep -q '^NoDisplay=true' "$f" && continue
69	printf '%s\n' "$f"
70	return 0
71	done
72	done \| head -n 1
73	}
74
75	# Exec= carries field codes (%u %U %f %F and friends) that are placeholders
76	# rather than arguments. Strip them all and append the URL ourselves, which is
77	# what a launcher is supposed to do and what alloy-menu already does for the
78	# same reason.
79	#
80	# Flatpak wraps its own markers around them, and they have to go too. A real
81	# exported entry reads:
82	#
83	# Exec=/usr/bin/flatpak run --branch=stable org.mozilla.firefox @@u %U @@
84	#
85	# `@@u` and the closing `@@` are flatpak's way of saying "the file or URI
86	# arguments belong here". Strip only the field code and the browser is
87	# launched with two literal arguments of `@@u` and `@@`, which it treats as
88	# URLs to open. Caught by testing against an exported entry rather than a
89	# hand-written one, which is the only reason it was visible.
90	exec_line() {
91	sed -n 's/^Exec=//p' "$1" \| head -n 1 \
92	\| sed 's/ @@[uUfF]//g; s/ @@//g; s/ *%[a-zA-Z]//g'
93	}
94
95	say() {
96	# Both channels on purpose. A link opened from the file manager or a
97	# notification has no terminal to read, and a link opened from a shell has
98	# no reason to raise a desktop notification.
99	printf '%s\n' "$1" >&2
100	if command -v notify-send >/dev/null 2>&1; then
101	notify-send -u normal -a Alloy "No browser installed" "$1" 2>/dev/null \|\| true
102	fi
103	}
104
105	url="${1:-}"
106	if [ -z "$url" ]; then
107	echo "usage: alloy-open URL" >&2
108	exit 2
109	fi
110
111	entry="$(browser_entry \|\| true)"
112
113	if [ -n "$entry" ]; then
114	cmd="$(exec_line "$entry")"
115	[ -n "$cmd" ] \|\| { say "The browser entry ${entry##*/} has no Exec line, so it cannot be launched."; exit 1; }
116	# shellcheck disable=SC2086
117	exec $cmd "$url"
118	fi
119
120	# No browser. This is the branch the script is for.
121	#
122	# Both routes named are ones that work today. `alloy browser` is the intended
123	# front door and does not exist yet, so it is deliberately NOT mentioned:
124	# telling someone to run a command that is not there is the same silent
125	# failure this script was written to remove, one level up. When that verb
126	# ships it replaces the flatpak line here.
127	#
128	# The layering route is named because it works: Firefox is in Fedora's own
129	# repos, and those stay enabled after install. That is the whole reason it is
130	# Alloy's pick (wiki `alloy-byo-principle`), so a machine that chose `none` is
131	# one command from the browser the image would have carried.
132	printf 'No browser is installed, so this link cannot be opened: %s\n' "$url" >&2
133	say "Install one with: rpm-ostree install firefox
134	Or, sandboxed: flatpak install org.mozilla.firefox, from a remote you have added
135	Or rebuild the image with BROWSER=firefox to bake one in."
136	exit 3
137