X-Git-Url: https://git.archive.openwrt.org/?p=project%2Fluci.git;a=blobdiff_plain;f=documentation%2FModulesHowTo.md;fp=documentation%2FModulesHowTo.md;h=3f70b788c5ddf8a00c855023d5373334d8b5b5ed;hp=0000000000000000000000000000000000000000;hb=4b11843e4ce3e7636d67cf3e987ae94ca8c8977d;hpb=37a9d6aee7ad944ea89754c31351ebae961793db diff --git a/documentation/ModulesHowTo.md b/documentation/ModulesHowTo.md new file mode 100644 index 000000000..3f70b788c --- /dev/null +++ b/documentation/ModulesHowTo.md @@ -0,0 +1,153 @@ +*Note:* If you plan to integrate your module into LuCI, you should read the [wiki:Documentation/Modules Module Reference] before. + +This tutorial describes how to write your own modules for the LuCI WebUI. +For this tutorial we refer to your LuCI installation direcotry as *lucidir_' (/usr/lib/lua/luci if you are working with an installed version) and assume your LuCI installation is reachable through your webserver via '_/cgi-bin/luci*. + +If you are working with the development environment replace *lucidir_' with '''''/path/to/your/luci/checkout''/applications/myapplication/luasrc''' (this is a default empty module you can use for your experiments) and your LuCI installation can probably be reached via http://localhost:8080/luci/ after you ran '_make runhttpd*. + + + +# Show me the way (The dispatching process) +To write a module you need to understand the basics of the dispatching process in LuCI. +LuCI uses a dispatching tree that will be built by executing the index-Function of every available controller. +The CGI-environment variable *PATH_INFO* will be used as the path in this dispatching tree, e.g.: /cgi-bin/luci/foo/bar/baz +will be resolved to foo.bar.baz + +To register a function in the dispatching tree, you can use the *entry*-function of _luci.dispatcher_. entry takes 4 arguments (2 are optional): + + entry(path, target, title=nil, order=nil) + + +* *path* is a table that describes the position in the dispatching tree: For example a path of {"foo", "bar", "baz"} would insert your node in foo.bar.baz. +* *target* describes the action that will be taken when a user requests the node. There are several predefined ones of which the 3 most important (call, template, cbi) are described later on on this page +* *title* defines the title that will be visible to the user in the menu (optional) +* *order* is a number with which nodes on the same level will be sorted in the menu (optional) + +You can assign more attributes by manipulating the node table returned by the entry-function. A few example attributes: + +* *i18n* defines which translation file should be automatically loaded when the page gets requested +* *dependent* protects plugins to be called out of their context if a parent node is missing +* *leaf* stops parsing the request at this node and goes no further in the dispatching tree +* *sysauth* requires the user to authenticate with a given system user account + + +# It's all about names (Naming and the module file) +Now that you know the basics about dispatching, we can start writing modules. But before you have to choose the category and name of your new digital child. + +We assume you want to create a new application "myapp" with a module "mymodule". + +So you have to create a new subdirectory *_lucidir''/controller/myapp''' with a file '_mymodule.lua* with the following content: + + module("luci.controller.myapp.mymodule", package.seeall) + + function index() + + end + + +The first line is required for Lua to correctly identify the module and create its scope. +The index-Function will be used to register actions in the dispatching tree. + + + +# Teaching your new child (Actions) +So it is there and has a name but it has no actions. + +We assume you want to reuse your module myapp.mymodule that you begun in the last step. + + +## Actions +Reopen *_lucidir_/controller/myapp/mymodule.lua* and just add a function to it so that its content looks like this example: + + + module("luci.controller.myapp.mymodule", package.seeall) + + function index() + entry({"click", "here", "now"}, call("action_tryme"), "Click here", 10).dependent=false + end + + function action_tryme() + luci.http.prepare_content("text/plain") + luci.http.write("Haha, rebooting now...") + luci.sys.reboot() + end + + +And now type */cgi-bin/luci/click/here/now_' ('_[http://localhost:8080/luci/click/here/now]* if you are using the development environment) in your browser. + +You see these action functions simple have to be added to a dispatching entry. + +As you might or might not know: CGI specification requires you to send a Content-Type header before you can send your content. You will find several shortcuts (like the one used above) as well as redirecting functions in the module *luci.http* + +## Views +If you only want to show the user a text or some interesting familiy photos it may be enough to use a HTML-template. These templates can also include some Lua code but be aware that writing whole office suites by only using these templates might be called "dirty" by other developers. + +Now let's create a little template *_lucidir_/view/myapp-mymodule/helloworld.htm* with the content: + + + <%+header%> +

<%:Hello World%>

+ <%+footer%> + + + +and add the following line to the index-Function of your module file. + + entry({"my", "new", "template"}, template("myapp-mymodule/helloworld"), "Hello world", 20).dependent=false + + +Now type */cgi-bin/luci/my/new/template_' ('_[http://localhost:8080/luci/my/new/template]* if you are using the development environment) in your browser. + +You may notice those fancy <% %>-Tags, these are [wiki:Documentation/Templates|template markups] used by the LuCI template processor. +It is always good to include header and footer at the beginning and end of a template as those create the default design and menu. + +## CBI models +The CBI is one of the uber coolest features of LuCI. It creates a formular based user interface and saves its contents to a specific UCI config file. You only have to describe the structure of the configuration file in a CBI model file and Luci does the rest of the work. This includes generating, parsing and validating a XHTML form and reading and writing the UCI file. + +So let's be serious at least for this paragraph and create a real pratical example *_lucidir_/model/cbi/myapp-mymodule/netifaces.lua* with the following contents: + + + m = Map("network", "Network") -- We want to edit the uci config file /etc/config/network + + s = m:section(TypedSection, "interface", "Interfaces") -- Especially the "interface"-sections + s.addremove = true -- Allow the user to create and remove the interfaces + function s:filter(value) + return value ~= "loopback" and value -- Don't touch loopback + end + s:depends("proto", "static") -- Only show those with "static" + s:depends("proto", "dhcp") -- or "dhcp" as protocol and leave PPPoE and PPTP alone + + p = s:option(ListValue, "proto", "Protocol") -- Creates an element list (select box) + p:value("static", "static") -- Key and value pairs + p:value("dhcp", "DHCP") + p.default = "static" + + s:option(Value, "ifname", "interface", "the physical interface to be used") -- This will give a simple textbox + + s:option(Value, "ipaddr", translate("ip", "IP Address")) -- Ja, das ist eine i18n-Funktion ;-) + + s:option(Value, "netmask", "Netmask"):depends("proto", "static") -- You may remember this "depends" function from above + + mtu = s:option(Value, "mtu", "MTU") + mtu.optional = true -- This one is very optional + + dns = s:option(Value, "dns", "DNS-Server") + dns:depends("proto", "static") + dns.optional = true + function dns:validate(value) -- Now, that's nifty, eh? + return value:match("[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+") -- Returns nil if it doesn't match otherwise returns match + end + + gw = s:option(Value, "gateway", "Gateway") + gw:depends("proto", "static") + gw.rmempty = true -- Remove entry if it is empty + + return m -- Returns the map + + +and of course don't forget to add something like this to your module's index-Function. + + entry({"admin", "network", "interfaces"}, cbi("myapp-mymodule/netifaces"), "Network interfaces", 30).dependent=false + + +There are many more features, see [wiki:Documentation/CBI the CBI reference] and the modules shipped with LuCI.