OpenWrt_Luci_Lua/1_1.mi_Lua/luci/template.lua
2015-06-28 14:39:56 +08:00

108 lines
3.0 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 9558 2012-12-18 13:58:22Z jow $
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 util = require "luci.util"
local config = require "luci.config"
local tparser = require "luci.template.parser"
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"
-- Define the namespace for template modules
context = util.threadlocal()
--- 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)
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 not self.template then
-- Compile template
local err
local sourcefile = viewdir .. "/" .. name .. ".htm"
self.template, _, err = tparser.parse(sourcefile)
-- If we have no valid template throw error, otherwise cache the template
if not self.template then
error("Failed to load template '" .. name .. "'.\n" ..
"Error while parsing template '" .. sourcefile .. "':\n" ..
(err or "Unknown syntax error"))
else
self.cache[name] = self.template
end
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("Failed to execute template '" .. self.name .. "'.\n" ..
"A runtime error occured: " .. tostring(err or "(nil)"))
end
end