openresty and lua multi-function template, it can correct show your error line.
You can use lua-resty-aries to render template and safety run lua code string.The template or code string can be from any kind of data source, such as: file, redis, mysql or mongodb, any you like. And lua-resty-aries can correct postion your template's error line.
support openresty1.0.6+, lua5.1+
lua-resty-aries support linux/ubantu, windows and mac.
you need install lua/luajit first http://www.lua.org/
with luarocks
luarocks install lua-resty-aries
local Aries = require("resty.aries")
local aries1 = Aries:new()
local result, err = aries1:compile([=[
<% hello = "welcome to lua-resty-aries" %>
<h1><center><%= hello %></center></h1>
]=])
print(result) -- <h1><center><%= hello %></center></h1>
We create index.html file at {workdir}/tpl/index.html
<!DOCTYPE html>
<html>
<head>
<title><%= ctx.title %></title>
</head>
<body>
<% hello = "welcome to lua-resty-aries" %>
<h1><center><%= hello %></center></h1>
</body>
</html>
We can render the template like this:
local Aries = require("resty.aries")
local aries1 = Aries:new()
local result, err = aries1:render("index", {
title="lua-resty-aries title"
})
print(result)
We create tpl/index2.html like this
<!DOCTYPE html>
<html>
<head>
<title><%= ctx.title %></title>
</head>
<body>
<% hello = "welcome to lua-resty-aries" %>
<h1><center><%= hello %></center></h1>
<% if (ctx.loop or 0) > 0 then %>
<% for i=1,ctx.loop,1 do %>
<% include inc/loop %>
<% end %>
<% else %>
<% include inc/noloop %>
<% end %>
</body>
</html>
create inc/noloop.html
<h1>ctx noloop</h1>
this must be occur an error, undefined function <% ctx.error() %>
ctx.loop=<%= ctx.loop %>
create inc/loop.html
<h1>ctx doloop</h1>
ctx.loop=<%= ctx.loop %>
create render code:
local Aries = require("resty.aries")
local aries1 = Aries:new()
local result, err = aries1:render("index2", {
title="lua-resty-aries title",
loop=10, --change loop to control loop times
})
print(result)
if we change render code like this, this must be occur an error:
local Aries = require("resty.aries")
local aries1 = Aries:new()
local result, err = aries1:render("index2", {
title="lua-resty-aries title",
loop=-1, --not loop make an errror
})
print(err) -- index2.html: 14 >> inc/noloop.html: 2 have error attempt to call field 'error' (a nil value)
we can get error msg, correct to postion the error line, even it at include template:
index2.html: 14 >> inc/noloop.html: 2 have error attempt to call field 'error' (a nil value)
Aries Constructor method. Every time, you call Aries:new(opt) will return a new Aries instance.
local Aries = require("resty.aries")
local ariesInstance = Aries:new(opt)
opt all attribute, all of these attributes are option:
-- below is the default value
opt = {
-- custom left half tag
startTag = "<%",
-- custom right half tag
endTag = "%>",
-- custom the template file's suffix
fileSuffix = "html",
-- change root of template folder path
rootPath = "./tpl",
-- works fine at linux and windows
sep = "/",
-- if occur error, show the error line and msg, this must set off in production to increase performance
isShowDetailError = true,
-- tpl parse cache,default is true,
cache = true,
-- tpl parse cache time, default expire 30min, unit second
cacheTime = 1800,
-- template render timeout, unit second
-- default not timeout
timeout = -1,
-- instance level object to put to template
ctx = {},
-- change template data source, you can get template from redis or other data source.
-- default is from file system
getInclude = function(self, includeName)
-- simple example get template from redis
-- local data, err = redis_conn:get(includeName)
-- return data == ngx.null and "" or data
return self.readfile(string.format("%s%s%s.%s", self.rootPath, self.sep, includeName, self.fileSuffix))
end,
-- before return string ,you can minify the html or xml string
-- default do nothing
minify = function(self, renderStr)
return renderStr
end,
}
Aries Instance Method
-- get all the include template name by name
local includeNameTable, err = ariesInstance:getIncludesByName(tplName string)
-- get all the include template name by string code
local includeNameTable, err = ariesInstance:getIncludesByContent(tplName string)
-- render a template by name
-- here ctx inherit the ariesInstance.ctx
local renderStr, err = ariesInstance:render(tplName string, [ctx table])
-- render a template by string code
-- here ctx inherit the ariesInstance.ctx
local renderStr, err = ariesInstance:compile(tplName string, [ctx table, tplName string])
We can use include {templateName} to include other template, lua-resty-aries will call ariesInstance:getInclude({templateName}) everytime.(include first we call ariesInstance:render({templateName})). example:
<% include inc/header %> -- notice,default not to add file suffix
print on template example:
-- will show hello world < > " '
<%= string.format("hello world %s %s %s %s", "<", ">", '"', "'") %>
-- will show hello world < > " '
<%= string.format("hello world %s %s %s %s", "<", ">", '"', "'") %>
ctx table on template:
-- like <%= {str} %>
ctx.print(str string)
-- like <%- {str} %>
ctx.rawPrint(str string)
-- lock some ctx attribute, before excute ctx.unlock({field}), you can't change such {field} value
-- example:
-- ctx.a = 1
-- ctx.lock(a)
-- ctx.a = 2 -- occur error
ctx.lock({field})
-- unlock field
-- example
-- ctx.a = 1
-- ctx.lock(a)
-- ctx.unlock(a)
-- ctx.a = 2 -- ok
ctx.unlock({field})