libs/web: dispatcher.lua: add support for external tree building and indexing

[project/luci.git] / libs / web / luasrc / dispatcher.lua

--[[
LuCI - Dispatcher

Description:
The request dispatcher and module dispatcher generators

FileId:
$Id$

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.

]]--

--- LuCI web dispatcher.
local fs = require "nixio.fs"
local sys = require "luci.sys"
local init = require "luci.init"
local util = require "luci.util"
local http = require "luci.http"
local nixio = require "nixio", require "nixio.util"

module("luci.dispatcher", package.seeall)
context = util.threadlocal()

authenticator = {}

-- Index table
local index = nil

-- Fastindex
local fi


--- Build the URL relative to the server webroot from given virtual path.
-- @param ...   Virtual path
-- @return              Relative URL
function build_url(...)
        local path = {...}
        local sn = http.getenv("SCRIPT_NAME") or ""
        for k, v in pairs(context.urltoken) do
                sn = sn .. "/;" .. k .. "=" .. http.urlencode(v)
        end
        return sn .. ((#path > 0) and "/" .. table.concat(path, "/") or "")
end

--- Send a 404 error code and render the "error404" template if available.
-- @param message       Custom error message (optional)
-- @return                      false
function error404(message)
        luci.http.status(404, "Not Found")
        message = message or "Not Found"

        require("luci.template")
        if not luci.util.copcall(luci.template.render, "error404") then
                luci.http.prepare_content("text/plain")
                luci.http.write(message)
        end
        return false
end

--- Send a 500 error code and render the "error500" template if available.
-- @param message       Custom error message (optional)#
-- @return                      false
function error500(message)
        luci.util.perror(message)
        if not context.template_header_sent then
                luci.http.status(500, "Internal Server Error")
                luci.http.prepare_content("text/plain")
                luci.http.write(message)
        else
                require("luci.template")
                if not luci.util.copcall(luci.template.render, "error500", {message=message}) then
                        luci.http.prepare_content("text/plain")
                        luci.http.write(message)
                end
        end
        return false
end

function authenticator.htmlauth(validator, accs, default)
        local user = luci.http.formvalue("username")
        local pass = luci.http.formvalue("password")

        if user and validator(user, pass) then
                return user
        end

        require("luci.i18n")
        require("luci.template")
        context.path = {}
        luci.template.render("sysauth", {duser=default, fuser=user})
        return false

end

--- Dispatch an HTTP request.
-- @param request       LuCI HTTP Request object
function httpdispatch(request, prefix, ext_tree)
        luci.http.context.request = request
        context.request = {}
        local pathinfo = http.urldecode(request:getenv("PATH_INFO") or "", true)

        for node in pathinfo:gmatch("[^/]+") do
                table.insert(context.request, node)
        end

        local stat, err = util.coxpcall(function()
                dispatch(context.request, ext_tree)
        end, error500)

        luci.http.close()

        --context._disable_memtrace()
end

--- Dispatches a LuCI virtual path.
-- @param request       Virtual path
function dispatch(request, ext_tree)
        context._disable_memtrace = require "luci.debug".trap_memtrace("l")
        local ctx = context
        ctx.path = request
        ctx.urltoken   = ctx.urltoken or {}

        local conf = require "luci.config"
        assert(conf.main,
                "/etc/config/luci seems to be corrupt, unable to find section 'main'")

        local lang = conf.main.lang
        if lang == "auto" then
                local aclang = http.getenv("HTTP_ACCEPT_LANGUAGE") or ""
                for lpat in aclang:gmatch("[%w-]+") do
                        lpat = lpat and lpat:gsub("-", "_")
                        if conf.languages[lpat] then
                                lang = lpat
                                break
                        end
                end
        end
        require "luci.i18n".setlanguage(lang)

        if ext_tree then
                ctx.index, ctx.tree, ctx.treecache, ctx.modifiers = unpack(ext_tree)
        elseif not ctx.tree then
                createtree()
        end

        local c = ctx.tree
        local stat
        local track = {}
        local args = {}
        ctx.args = args
        ctx.requestargs = ctx.requestargs or args
        local n
        local t = true
        local token = ctx.urltoken
        local preq = {}
        local freq = {}

        for i, s in ipairs(request) do
                local tkey, tval
                if t then
                        tkey, tval = s:match(";(%w+)=(.*)")
                end

                if tkey then
                        token[tkey] = tval
                else
                        t = false
                        preq[#preq+1] = s
                        freq[#freq+1] = s
                        c = c.nodes[s]
                        n = i
                        if not c then
                                break
                        end

                        util.update(track, c)

                        if c.leaf then
                                break
                        end
                end
        end

        if c and c.leaf then
                for j=n+1, #request do
                        args[#args+1] = request[j]
                        freq[#freq+1] = request[j]
                end
        end

        ctx.requestpath = freq
        ctx.path = preq

        if track.i18n then
                require("luci.i18n").loadc(track.i18n)
        end

        -- Init template engine
        if (c and c.index) or not track.notemplate then
                local tpl = require("luci.template")
                local media = track.mediaurlbase or luci.config.main.mediaurlbase
                if not tpl.Template("themes/%s/header" % fs.basename(media)) then 
                --if not pcall(tpl.Template, "themes/%s/header" % fs.basename(media)) then
                        media = nil
                        for name, theme in pairs(luci.config.themes) do
                                if name:sub(1,1) ~= "." and pcall(tpl.Template,
                                 "themes/%s/header" % fs.basename(theme)) then
                                        media = theme
                                end
                        end
                        assert(media, "No valid theme found")
                end

                tpl.context.viewns = setmetatable({
                        write       = luci.http.write;
                        include     = function(name) tpl.Template(name):render(getfenv(2)) end;
                        translate   = function(...) return require("luci.i18n").translate(...) end;
                        striptags   = util.striptags;
                        media       = media;
                        theme       = fs.basename(media);
                        resource    = luci.config.main.resourcebase
                }, {__index=function(table, key)
                        if key == "controller" then
                                return build_url()
                        elseif key == "REQUEST_URI" then
                                return build_url(unpack(ctx.requestpath))
                        else
                                return rawget(table, key) or _G[key]
                        end
                end})
        end

        track.dependent = (track.dependent ~= false)
        assert(not track.dependent or not track.auto, "Access Violation")

        if track.sysauth then
                local sauth = require "luci.sauth"

                local authen = type(track.sysauth_authenticator) == "function"
                 and track.sysauth_authenticator
                 or authenticator[track.sysauth_authenticator]

                local def  = (type(track.sysauth) == "string") and track.sysauth
                local accs = def and {track.sysauth} or track.sysauth
                local sess = ctx.authsession
                local verifytoken = false
                if not sess then
                        sess = luci.http.getcookie("sysauth")
                        sess = sess and sess:match("^[a-f0-9]+$")
                        verifytoken = true
                end

                local sdat = sauth.read(sess)
                local user

                if sdat then
                        sdat = loadstring(sdat)
                        setfenv(sdat, {})
                        sdat = sdat()
                        if not verifytoken or ctx.urltoken.stok == sdat.token then
                                user = sdat.user
                        end
                end

                if not util.contains(accs, user) then
                        if authen then
                                ctx.urltoken.stok = nil
                                local user, sess = authen(luci.sys.user.checkpasswd, accs, def)
                                if not user or not util.contains(accs, user) then
                                        return
                                else
                                        local sid = sess or luci.sys.uniqueid(16)
                                        if not sess then
                                                local token = luci.sys.uniqueid(16)
                                                sauth.write(sid, util.get_bytecode({
                                                        user=user,
                                                        token=token,
                                                        secret=luci.sys.uniqueid(16)
                                                }))
                                                ctx.urltoken.stok = token
                                        end
                                        luci.http.header("Set-Cookie", "sysauth=" .. sid.."; path="..build_url())
                                        ctx.authsession = sid
                                end
                        else
                                luci.http.status(403, "Forbidden")
                                return
                        end
                else
                        ctx.authsession = sess
                end
        end

        if track.setgroup then
                luci.sys.process.setgroup(track.setgroup)
        end

        if track.setuser then
                luci.sys.process.setuser(track.setuser)
        end

        local target = nil
        if c then
                if type(c.target) == "function" then
                        target = c.target
                elseif type(c.target) == "table" then
                        target = c.target.target
                end
        end

        if c and (c.index or type(target) == "function") then
                ctx.dispatched = c
                ctx.requested = ctx.requested or ctx.dispatched
        end

        if c and c.index then
                local tpl = require "luci.template"

                if util.copcall(tpl.render, "indexer", {}) then
                        return true
                end
        end

        if type(target) == "function" then
                util.copcall(function()
                        local oldenv = getfenv(target)
                        local module = require(c.module)
                        local env = setmetatable({}, {__index=

                        function(tbl, key)
                                return rawget(tbl, key) or module[key] or oldenv[key]
                        end})

                        setfenv(target, env)
                end)

                if type(c.target) == "table" then
                        target(c.target, unpack(args))
                else
                        target(unpack(args))
                end
        else
                error404()
        end
end

--- Generate the dispatching index using the best possible strategy.
function createindex()
        local path = luci.util.libpath() .. "/controller/"
        local suff = { ".lua", ".lua.gz" }

        if luci.util.copcall(require, "luci.fastindex") then
                return createindex_fastindex(path, suff)
        else
                return createindex_plain(path, suff)
        end
end

--- Generate the dispatching index using the fastindex C-indexer.
-- @param path          Controller base directory
-- @param suffixes      Controller file suffixes
function createindex_fastindex(path, suffixes)
        local index = {}

        if not fi then
                fi = luci.fastindex.new("index")
                for _, suffix in ipairs(suffixes) do
                        fi.add(path .. "*" .. suffix)
                        fi.add(path .. "*/*" .. suffix)
                end
        end
        fi.scan()

        for k, v in pairs(fi.indexes) do
                index[v[2]] = v[1]
        end

        return index
end

--- Generate the dispatching index using the native file-cache based strategy.
-- @param path          Controller base directory
-- @param suffixes      Controller file suffixes
function createindex_plain(path, suffixes)
        local controllers = { }
        for _, suffix in ipairs(suffixes) do
                nixio.util.consume((fs.glob(path .. "*" .. suffix)), controllers)
                nixio.util.consume((fs.glob(path .. "*/*" .. suffix)), controllers)
        end

        if indexcache then
                local cachedate = fs.stat(indexcache, "mtime")
                if cachedate then
                        local realdate = 0
                        for _, obj in ipairs(controllers) do
                                local omtime = fs.stat(path .. "/" .. obj, "mtime")
                                realdate = (omtime and omtime > realdate) and omtime or realdate
                        end

                        if cachedate > realdate then
                                assert(
                                        sys.process.info("uid") == fs.stat(indexcache, "uid")
                                        and fs.stat(indexcache, "modestr") == "rw-------",
                                        "Fatal: Indexcache is not sane!"
                                )

                                index = loadfile(indexcache)()
                                return index
                        end
                end
        end

        local index = {}

        for i,c in ipairs(controllers) do
                local module = "luci.controller." .. c:sub(#path+1, #c):gsub("/", ".")
                for _, suffix in ipairs(suffixes) do
                        module = module:gsub(suffix.."$", "")
                end

                local mod = require(module)
                local idx = mod.index

                if type(idx) == "function" then
                        index[module] = idx
                end
        end

        if indexcache then
                local f = nixio.open(indexcache, "w", 600)
                f:writeall(util.get_bytecode(index))
                f:close()
        end

        return index
end

--- Create the dispatching tree from the index.
-- Build the index before if it does not exist yet.
function createtree()
        local ctx   = context
        local tree  = {nodes={}}
        local cache = setmetatable({}, {__mode="v"})
        local modi  = {}

        if not ctx.index then
                ctx.index = createindex()
        end

        ctx.tree      = tree
        ctx.treecache = cache
        ctx.modifiers = modi

        -- Load default translation
        require "luci.i18n".loadc("default")

        local scope = setmetatable({}, {__index = luci.dispatcher})

        for k, v in pairs(ctx.index) do
                scope._NAME = k
                setfenv(v, scope)
                pcall(v)
        end

        local function modisort(a,b)
                return modi[a].order < modi[b].order
        end

        for _, v in util.spairs(modi, modisort) do
                scope._NAME = v.module
                setfenv(v.func, scope)
                pcall(v.func)
        end

        return { index, tree, cache, modi }
end

--- Register a tree modifier.
-- @param       func    Modifier function
-- @param       order   Modifier order value (optional)
function modifier(func, order)
        context.modifiers[#context.modifiers+1] = {
                func = func,
                order = order or 0,
                module
                        = getfenv(2)._NAME
        }
end

--- Clone a node of the dispatching tree to another position.
-- @param       path    Virtual path destination
-- @param       clone   Virtual path source
-- @param       title   Destination node title (optional)
-- @param       order   Destination node order value (optional)
-- @return                      Dispatching tree node
function assign(path, clone, title, order)
        local obj  = node(unpack(path))
        obj.nodes  = nil
        obj.module = nil

        obj.title = title
        obj.order = order

        setmetatable(obj, {__index = _create_node(clone)})

        return obj
end

--- Create a new dispatching node and define common parameters.
-- @param       path    Virtual path
-- @param       target  Target function to call when dispatched.
-- @param       title   Destination node title
-- @param       order   Destination node order value (optional)
-- @return                      Dispatching tree node
function entry(path, target, title, order)
        local c = node(unpack(path))

        c.target = target
        c.title  = title
        c.order  = order
        c.module = getfenv(2)._NAME

        return c
end

--- Fetch or create a dispatching node without setting the target module or
-- enabling the node.
-- @param       ...             Virtual path
-- @return                      Dispatching tree node
function get(...)
        return _create_node({...})
end

--- Fetch or create a new dispatching node.
-- @param       ...             Virtual path
-- @return                      Dispatching tree node
function node(...)
        local c = _create_node({...})

        c.module = getfenv(2)._NAME
        c.auto = nil

        return c
end

function _create_node(path, cache)
        if #path == 0 then
                return context.tree
        end

        cache = cache or context.treecache
        local name = table.concat(path, ".")
        local c = cache[name]

        if not c then
                local new = {nodes={}, auto=true, path=util.clone(path)}
                local last = table.remove(path)

                c = _create_node(path, cache)

                c.nodes[last] = new
                cache[name] = new

                return new
        else
                return c
        end
end

-- Subdispatchers --

--- Create a redirect to another dispatching node.
-- @param       ...             Virtual path destination
function alias(...)
        local req = {...}
        return function(...)
                for _, r in ipairs({...}) do
                        req[#req+1] = r
                end

                dispatch(req)
        end
end

--- Rewrite the first x path values of the request.
-- @param       n               Number of path values to replace
-- @param       ...             Virtual path to replace removed path values with
function rewrite(n, ...)
        local req = {...}
        return function(...)
                local dispatched = util.clone(context.dispatched)

                for i=1,n do
                        table.remove(dispatched, 1)
                end

                for i, r in ipairs(req) do
                        table.insert(dispatched, i, r)
                end

                for _, r in ipairs({...}) do
                        dispatched[#dispatched+1] = r
                end

                dispatch(dispatched)
        end
end


local function _call(self, ...)
        if #self.argv > 0 then
                return getfenv()[self.name](unpack(self.argv), ...)
        else
                return getfenv()[self.name](...)
        end
end

--- Create a function-call dispatching target.
-- @param       name    Target function of local controller
-- @param       ...             Additional parameters passed to the function
function call(name, ...)
        return {type = "call", argv = {...}, name = name, target = _call}
end


local _template = function(self, ...)
        require "luci.template".render(self.view)
end

--- Create a template render dispatching target.
-- @param       name    Template to be rendered
function template(name)
        return {type = "template", view = name, target = _template}
end


local function _cbi(self, ...)
        local cbi = require "luci.cbi"
        local tpl = require "luci.template"
        local http = require "luci.http"

        local config = self.config or {}
        local maps = cbi.load(self.model, ...)

        local state = nil

        for i, res in ipairs(maps) do
                res.flow = config
                local cstate = res:parse()
                if cstate and (not state or cstate < state) then
                        state = cstate
                end
        end

        local function _resolve_path(path)
                return type(path) == "table" and build_url(unpack(path)) or path
        end

        if config.on_valid_to and state and state > 0 and state < 2 then
                http.redirect(_resolve_path(config.on_valid_to))
                return
        end

        if config.on_changed_to and state and state > 1 then
                http.redirect(_resolve_path(config.on_changed_to))
                return
        end

        if config.on_success_to and state and state > 0 then
                http.redirect(_resolve_path(config.on_success_to))
                return
        end

        if config.state_handler then
                if not config.state_handler(state, maps) then
                        return
                end
        end

        local pageaction = true
        http.header("X-CBI-State", state or 0)
        if not config.noheader then
                tpl.render("cbi/header", {state = state})
        end
        for i, res in ipairs(maps) do
                res:render()
                if res.pageaction == false then
                        pageaction = false
                end
        end
        if not config.nofooter then
                tpl.render("cbi/footer", {flow = config, pageaction=pageaction, state = state, autoapply = config.autoapply})
        end
end

--- Create a CBI model dispatching target.
-- @param       model   CBI model to be rendered
function cbi(model, config)
        return {type = "cbi", config = config, model = model, target = _cbi}
end


local function _arcombine(self, ...)
        local argv = {...}
        local target = #argv > 0 and self.targets[2] or self.targets[1]
        setfenv(target.target, self.env)
        target:target(unpack(argv))
end

--- Create a combined dispatching target for non argv and argv requests.
-- @param trg1  Overview Target
-- @param trg2  Detail Target
function arcombine(trg1, trg2)
        return {type = "arcombine", env = getfenv(), target = _arcombine, targets = {trg1, trg2}}
end


local function _form(self, ...)
        local cbi = require "luci.cbi"
        local tpl = require "luci.template"
        local http = require "luci.http"

        local maps = luci.cbi.load(self.model, ...)
        local state = nil

        for i, res in ipairs(maps) do
                local cstate = res:parse()
                if cstate and (not state or cstate < state) then
                        state = cstate
                end
        end

        http.header("X-CBI-State", state or 0)
        tpl.render("header")
        for i, res in ipairs(maps) do
                res:render()
        end
        tpl.render("footer")
end

--- Create a CBI form model dispatching target.
-- @param       model   CBI form model tpo be rendered
function form(model)
        return {type = "cbi", model = model, target = _form}
end