flm01/mote/v1/openwrt/package/luci/libs/web/luasrc/template.lua

240 lines
6.3 KiB
Lua

--[[
LuCI - Template Parser
Description:
A template parser supporting includes, translations, Lua code blocks
and more. It can be used either as a compiler or as an interpreter.
FileId: $Id: template.lua 3246 2008-09-12 07:48:36Z Cyrus $
License:
Copyright 2008 Steven Barth <steven@midlink.org>
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
]]--
local fs = require"luci.fs"
local sys = require "luci.sys"
local util = require "luci.util"
local table = require "table"
local string = require "string"
local config = require "luci.config"
local coroutine = require "coroutine"
local tostring, pairs, loadstring = tostring, pairs, loadstring
local setmetatable, loadfile = setmetatable, loadfile
local getfenv, setfenv, rawget = getfenv, setfenv, rawget
local assert, type, error = assert, type, error
--- LuCI template library.
module "luci.template"
config.template = config.template or {}
viewdir = config.template.viewdir or util.libpath() .. "/view"
compiledir = config.template.compiledir or util.libpath() .. "/view"
-- Compile modes:
-- memory: Always compile, do not save compiled files, ignore precompiled
-- file: Compile on demand, save compiled files, update precompiled
compiler_mode = config.template.compiler_mode or "memory"
-- Define the namespace for template modules
context = util.threadlocal()
--- Manually compile a given template into an executable Lua function
-- @param template LuCI template
-- @return Lua template function
function compile(template)
local expr = {}
-- Search all <% %> expressions
local function expr_add(ws1, skip1, command, skip2, ws2)
expr[#expr+1] = command
return ( #skip1 > 0 and "" or ws1 ) ..
"<%" .. tostring(#expr) .. "%>" ..
( #skip2 > 0 and "" or ws2 )
end
-- Save all expressiosn to table "expr"
template = template:gsub("(%s*)<%%(%-?)(.-)(%-?)%%>(%s*)", expr_add)
local function sanitize(s)
s = "%q" % s
return s:sub(2, #s-1)
end
-- Escape and sanitize all the template (all non-expressions)
template = sanitize(template)
-- Template module header/footer declaration
local header = 'write("'
local footer = '")'
template = header .. template .. footer
-- Replacements
local r_include = '")\ninclude("%s")\nwrite("'
local r_i18n = '"..translate("%1","%2").."'
local r_i18n2 = '"..translate("%1", "").."'
local r_pexec = '"..(%s or "").."'
local r_exec = '")\n%s\nwrite("'
-- Parse the expressions
for k,v in pairs(expr) do
local p = v:sub(1, 1)
v = v:gsub("%%", "%%%%")
local re = nil
if p == "+" then
re = r_include:format(sanitize(string.sub(v, 2)))
elseif p == ":" then
if v:find(" ") then
re = sanitize(v):gsub(":(.-) (.*)", r_i18n)
else
re = sanitize(v):gsub(":(.+)", r_i18n2)
end
elseif p == "=" then
re = r_pexec:format(v:sub(2))
elseif p == "#" then
re = ""
else
re = r_exec:format(v)
end
template = template:gsub("<%%"..tostring(k).."%%>", re)
end
return loadstring(template)
end
--- Render a certain template.
-- @param name Template name
-- @param scope Scope to assign to template (optional)
function render(name, scope)
return Template(name):render(scope or getfenv(2))
end
-- Template class
Template = util.class()
-- Shared template cache to store templates in to avoid unnecessary reloading
Template.cache = setmetatable({}, {__mode = "v"})
-- Constructor - Reads and compiles the template on-demand
function Template.__init__(self, name)
local function _encode_filename(str)
local function __chrenc( chr )
return "%%%02x" % string.byte( chr )
end
if type(str) == "string" then
str = str:gsub(
"([^a-zA-Z0-9$_%-%.%+!*'(),])",
__chrenc
)
end
return str
end
self.template = self.cache[name]
self.name = name
-- Create a new namespace for this template
self.viewns = context.viewns
-- If we have a cached template, skip compiling and loading
if self.template then
return
end
-- Enforce cache security
local cdir = compiledir .. "/" .. sys.process.info("uid")
-- Compile and build
local sourcefile = viewdir .. "/" .. name
local compiledfile = cdir .. "/" .. _encode_filename(name) .. ".lua"
local err
if compiler_mode == "file" then
local tplmt = fs.mtime(sourcefile) or fs.mtime(sourcefile .. ".htm")
local commt = fs.mtime(compiledfile)
if not fs.mtime(cdir) then
fs.mkdir(cdir, true)
fs.chmod(fs.dirname(cdir), "a+rxw")
end
assert(tplmt or commt, "No such template: " .. name)
-- Build if there is no compiled file or if compiled file is outdated
if not commt or (commt and tplmt and commt < tplmt) then
local source
source, err = fs.readfile(sourcefile) or fs.readfile(sourcefile .. ".htm")
if source then
local compiled, err = compile(source)
fs.writefile(compiledfile, util.get_bytecode(compiled))
fs.chmod(compiledfile, "a-rwx,u+rw")
self.template = compiled
end
else
assert(
sys.process.info("uid") == fs.stat(compiledfile, "uid")
and fs.stat(compiledfile, "mode") == "rw-------",
"Fatal: Cachefile is not sane!"
)
self.template, err = loadfile(compiledfile)
end
elseif compiler_mode == "memory" then
local source
source, err = fs.readfile(sourcefile) or fs.readfile(sourcefile .. ".htm")
if source then
self.template, err = compile(source)
end
end
-- If we have no valid template throw error, otherwise cache the template
if not self.template then
error(err)
else
self.cache[name] = self.template
end
end
-- Renders a template
function Template.render(self, scope)
scope = scope or getfenv(2)
-- Put our predefined objects in the scope of the template
setfenv(self.template, setmetatable({}, {__index =
function(tbl, key)
return rawget(tbl, key) or self.viewns[key] or scope[key]
end}))
-- Now finally render the thing
local stat, err = util.copcall(self.template)
if not stat then
error("Error in template %s: %s" % {self.name, err})
end
end