File

util/template.lua @ 10066:216ae100c04a

mod_pep: Only log when creating new pubsub services Once upon a time get_pep_service() would get called with random bare JIDs and remote hostnames, which is why it was logged this way. This seems to have been fixed, so it's not as useful anymore. It's still useful to know when it creates a new service object.
author Kim Alvefur <zash@zash.se>
date Tue, 09 Jul 2019 15:12:32 +0200
parent 8555:4f0f5b49bb03
child 12975:d10957394a3c
line wrap: on
line source

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