2 FFLuCI - Template Parser
5 A template parser supporting includes, translations, Lua code blocks
6 and more. It can be used either as a compiler or as an interpreter.
11 Copyright 2008 Steven Barth <steven@midlink.org>
13 Licensed under the Apache License, Version 2.0 (the "License");
14 you may not use this file except in compliance with the License.
15 You may obtain a copy of the License at
17 http://www.apache.org/licenses/LICENSE-2.0
19 Unless required by applicable law or agreed to in writing, software
20 distributed under the License is distributed on an "AS IS" BASIS,
21 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
22 See the License for the specific language governing permissions and
23 limitations under the License.
26 module("ffluci.template", package.seeall)
28 require("ffluci.config")
29 require("ffluci.util")
31 require("ffluci.i18n")
32 require("ffluci.model.uci")
34 viewdir = ffluci.fs.dirname(ffluci.util.__file__()) .. "view/"
38 -- none: Never compile, only use precompiled data from files
39 -- memory: Always compile, do not save compiled files, ignore precompiled
40 -- file: Compile on demand, save compiled files, update precompiled
41 compiler_mode = "memory"
44 -- This applies to compiler modes "always" and "smart"
46 -- Produce compiled lua code rather than lua sourcecode
47 -- WARNING: Increases template size heavily!!!
48 -- This produces the same bytecode as luac but does not have a strip option
49 compiler_enable_bytecode = false
52 -- Define the namespace for template modules
54 translate = ffluci.i18n.translate,
55 config = ffluci.model.uci.get,
56 controller = os.getenv("SCRIPT_NAME"),
57 media = ffluci.config.mediaurlbase,
59 include = function(name) Template(name):render(getfenv(2)) end,
62 -- Compiles a given template into an executable Lua module
63 function compile(template)
64 -- Search all <% %> expressions (remember: Lua table indexes begin with #1)
65 local function expr_add(command)
66 table.insert(expr, command)
67 return "<%" .. tostring(#expr) .. "%>"
70 -- As "expr" should be local, we have to assign it to the "expr_add" scope
72 ffluci.util.extfenv(expr_add, "expr", expr)
74 -- Save all expressiosn to table "expr"
75 template = template:gsub("<%%(.-)%%>", expr_add)
77 local function sanitize(s)
78 s = ffluci.util.escape(s)
79 s = ffluci.util.escape(s, "'")
80 s = ffluci.util.escape(s, "\n")
84 -- Escape and sanitize all the template (all non-expressions)
85 template = sanitize(template)
87 -- Template module header/footer declaration
88 local header = "write('"
91 template = header .. template .. footer
94 local r_include = "')\ninclude('%s')\nwrite('"
95 local r_i18n = "'..translate('%1','%2')..'"
96 local r_uci = "'..config('%1','%2','%3')..'"
97 local r_pexec = "'..%s..'"
98 local r_exec = "')\n%s\nwrite('"
100 -- Parse the expressions
101 for k,v in pairs(expr) do
102 local p = v:sub(1, 1)
105 re = r_include:format(sanitize(string.sub(v, 2)))
107 re = sanitize(v):gsub(":(.-) (.+)", r_i18n)
109 re = sanitize(v):gsub("~(.-)%.(.-)%.(.+)", r_uci)
111 re = r_pexec:format(string.sub(v, 2))
113 re = r_exec:format(v)
115 template = template:gsub("<%%"..tostring(k).."%%>", re)
118 if compiler_enable_bytecode then
119 tf = loadstring(template)
120 template = string.dump(tf)
126 -- Oldstyle render shortcut
127 function render(name, ...)
128 local s, t = pcall(Template, name)
130 error("Unable to load template: " .. name)
138 Template = ffluci.util.class()
140 -- Shared template cache to store templates in to avoid unnecessary reloading
144 -- Constructor - Reads and compiles the template on-demand
145 function Template.__init__(self, name)
146 if self.cache[name] then
147 self.template = self.cache[name]
152 -- Create a new namespace for this template
155 -- Copy over from general namespace
156 for k, v in pairs(viewns) do
160 -- If we have a cached template, skip compiling and loading
161 if self.template then
166 local sourcefile = viewdir .. name .. ".htm"
167 local compiledfile = viewdir .. name .. ".lua"
169 if compiler_mode == "file" then
170 local tplmt = ffluci.fs.mtime(sourcefile)
171 local commt = ffluci.fs.mtime(compiledfile)
173 -- Build if there is no compiled file or if compiled file is outdated
174 if ((commt == nil) and not (tplmt == nil))
175 or (not (commt == nil) and not (tplmt == nil) and commt < tplmt) then
176 local compiled = compile(ffluci.fs.readfile(sourcefile))
177 ffluci.fs.writefile(compiledfile, compiled)
178 self.template = loadstring(compiled)
180 self.template = loadfile(compiledfile)
183 elseif compiler_mode == "none" then
184 self.template = loadfile(self.compiledfile)
186 elseif compiler_mode == "memory" then
187 self.template = loadstring(compile(ffluci.fs.readfile(sourcefile)))
190 error("Invalid compiler mode: " .. compiler_mode)
194 -- If we have no valid template throw error, otherwise cache the template
195 if not self.template then
196 error("Unable to load template: " .. name)
198 self.cache[name] = self.template
203 -- Renders a template
204 function Template.render(self, scope)
205 scope = scope or getfenv(2)
207 -- Save old environment
208 local oldfenv = getfenv(self.template)
210 -- Put our predefined objects in the scope of the template
211 ffluci.util.updfenv(self.template, scope)
212 ffluci.util.updfenv(self.template, self.viewns)
214 -- Now finally render the thing
218 setfenv(self.template, oldfenv)