File

util/template.lua @ 13014:06453c564141

util.startup: Add prosody.started promise to easily execute code after startup To avoid a race where server-started fires before the promise function body is run (on next tick), I moved server-started to fire on the next tick, which seems sensible anyway. Errors are logged, I'm not sure if we ought to be doing something more here. I'm sure we'll find out.
author Matthew Wild <mwild1@gmail.com>
date Sat, 01 Apr 2023 11:56:38 +0100
parent 12975:d10957394a3c
line wrap: on
line source

-- luacheck: ignore 213/i
local stanza_mt = require "prosody.util.stanza".stanza_mt;
local setmetatable = setmetatable;
local pairs = pairs;
local ipairs = ipairs;
local error = error;
local envload = require "prosody.util.envload".envload;
local debug = debug;
local t_remove = table.remove;
local parse_xml = require "prosody.util.xml".parse;

local _ENV = nil;
-- luacheck: std none

local function trim_xml(stanza)
	for i=#stanza,1,-1 do
		local child = stanza[i];
		if child.name then
			trim_xml(child);
		else
			child = child:gsub("^%s*", ""):gsub("%s*$", "");
			stanza[i] = child;
			if child == "" then t_remove(stanza, i); end
		end
	end
end

local function create_string_string(str)
	str = ("%q"):format(str);
	str = str:gsub("{([^}]*)}", function(s)
		return '"..(data["'..s..'"]or"").."';
	end);
	return str;
end
local function create_attr_string(attr, xmlns)
	local str = '{';
	for name,value in pairs(attr) do
		if name ~= "xmlns" or value ~= xmlns then
			str = str..("[%q]=%s;"):format(name, create_string_string(value));
		end
	end
	return str..'}';
end
local function create_clone_string(stanza, lookup, xmlns)
	if not lookup[stanza] then
		local s = ('setmetatable({name=%q,attr=%s,tags={'):format(stanza.name, create_attr_string(stanza.attr, xmlns));
		-- add tags
		for i,tag in ipairs(stanza.tags) do
			s = s..create_clone_string(tag, lookup, stanza.attr.xmlns)..";";
		end
		s = s..'};';
		-- add children
		for i,child in ipairs(stanza) do
			if child.name then
				s = s..create_clone_string(child, lookup, stanza.attr.xmlns)..";";
			else
				s = s..create_string_string(child)..";"
			end
		end
		s = s..'}, stanza_mt)';
		s = s:gsub('%.%.""', ""):gsub('([=;])""%.%.', "%1"):gsub(';"";', ";"); -- strip empty strings
		local n = #lookup + 1;
		lookup[n] = s;
		lookup[stanza] = "_"..n;
	end
	return lookup[stanza];
end
local function create_cloner(stanza, chunkname)
	local lookup = {};
	local name = create_clone_string(stanza, lookup, "");
	local src = "local setmetatable,stanza_mt=...;return function(data)";
	for i=1,#lookup do
		src = src.."local _"..i.."="..lookup[i]..";";
	end
	src = src.."return "..name..";end";
	local f,err = envload(src, chunkname);
	if not f then error(err); end
	return f(setmetatable, stanza_mt);
end

local template_mt = { __tostring = function(t) return t.name end };
local function create_template(templates, text)
	local stanza, err = parse_xml(text);
	if not stanza then error(err); end
	trim_xml(stanza);

	local info = debug.getinfo(3, "Sl");
	info = info and ("template(%s:%d)"):format(info.short_src:match("[^\\/]*$"), info.currentline) or "template(unknown)";

	local template = setmetatable({ apply = create_cloner(stanza, info), name = info, text = text }, template_mt);
	templates[text] = template;
	return template;
end

local templates = setmetatable({}, { __mode = 'k', __index = create_template });
return function(text)
	return templates[text];
end;