util.signal: Add support for signalfd(2) on Linux
signalfd allows handling signal events using the same method as sockets,
via file descriptors. Thus all signal dispatch can go through the same
main event loop as everything else, removing need for thread-scary
signal handling where execution would just jump to the signal handler
regardless of the state of Lua, and needing to keep track of Lua
states/threads.
module:set_global();
local server = require "prosody.net.http.server";
local codes = require "prosody.net.http.codes";
local xml_escape = require "prosody.util.stanza".xml_escape;
local render = require "prosody.util.interpolation".new("%b{}", xml_escape);
local show_private = module:get_option_boolean("http_errors_detailed", false);
local always_serve = module:get_option_boolean("http_errors_always_show", true);
local default_message = { module:get_option_string("http_errors_default_message", "That's all I know.") };
local default_messages = {
[400] = { "What kind of request do you call that??" };
[403] = { "You're not allowed to do that." };
[404] = { "Whatever you were looking for is not here. %";
"Where did you put it?", "It's behind you.", "Keep looking." };
[500] = { "% Check your error log for more info.";
"Gremlins.", "It broke.", "Don't look at me." };
["/"] = {
"A study in simplicity.";
"Better catch it!";
"Don't just stand there, go after it!";
"Well, say something, before it runs too far!";
"Welcome to the world of XMPP!";
"You can do anything in XMPP!"; -- "The only limit is XML.";
"You can do anything with Prosody!"; -- the only limit is memory?
};
};
local messages = setmetatable(module:get_option("http_errors_messages", {}), { __index = default_messages });
local html = [[
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>{title}</title>
<style>
:root{color-scheme:light dark}
body{margin-top:14%;text-align:center;font-family:sans-serif}
h1{font-size:xx-large}
p{font-size:x-large}
p.warning>span{font-size:large;background-color:yellow}
p.extra{font-size:large;font-family:courier}
@media(prefers-color-scheme:dark){
p.warning>span{background-color:inherit;color:yellow}
}
</style>
</head>
<body>
<h1>{icon?{icon_raw!?}} {title}</h1>
<p>{message}</p>
{warning&<p class="warning"><span>⚠ {warning?} ⚠</span></p>}
{extra&<p class="extra">{extra?}</p>}
</body>
</html>
]];
local function get_page(code, extra)
local message = messages[code];
if always_serve or message then
message = message or default_message;
return render(html, {
title = rawget(codes, code) or ("Code "..tostring(code));
message = message[1]:gsub("%%", function ()
return message[math.random(2, math.max(#message,2))];
end);
extra = extra;
});
end
end
-- Main error page handler
module:hook_object_event(server, "http-error", function (event)
if event.response then
event.response.headers.content_type = "text/html; charset=utf-8";
end
return get_page(event.code, (show_private and event.private_message) or event.message or (event.error and event.error.text));
end);
-- Way to use the template for other things so to give a consistent appearance
module:hook("http-message", function (event)
if event.response then
event.response.headers.content_type = "text/html; charset=utf-8";
end
return render(html, event);
end, -1);
local icon = [[
<svg xmlns="http://www.w3.org/2000/svg" height="0.7em" viewBox="0 0 480 480" width="0.7em">
<rect fill="#6197df" height="220" rx="60" ry="60" width="220" x="10" y="10"></rect>
<rect fill="#f29b00" height="220" rx="60" ry="60" width="220" x="10" y="240"></rect>
<rect fill="#f29b00" height="220" rx="60" ry="60" width="220" x="240" y="10"></rect>
<rect fill="#6197df" height="220" rx="60" ry="60" width="220" x="240" y="240"></rect>
</svg>
]];
-- Something nicer shown instead of 404 at the root path, if nothing else handles this path
module:hook_object_event(server, "http-error", function (event)
local request, response = event.request, event.response;
if request and response and request.path == "/" and response.status_code == 404 then
response.status_code = 200;
response.headers.content_type = "text/html; charset=utf-8";
local message = messages["/"];
return render(html, {
icon_raw = icon,
title = "Prosody is running!";
message = message[math.random(#message)];
});
end
end, 1);