require "xmliter" -- require "util" --[[ Work in progress. Quick summary: xstring(node) => immediate string contents of node. returns nil,error on mixed content xtext(node) => recursive string contents of node Views v = xmlview.string(node) v.date => finds a child element named date and returns xstring(date) ]] --[[ INFO 12:50 upstream1 upstream2 This is a test message tree=lxptree.parsestring(s) sv = xmlview.string(tree) print(sv.type) -- "INFO" print(sv.time) -- "12:50" print(sv.empty) -- "" print(sv.receivedfrom) -- error "contains duplicate content" print(sv.body) -- error "contains mixed content" ]] local Public = {} xmlview = Public local tree_key = {"tree_key"} local cachecomplete_key = {"cachecomplete_key"} local populate_key = {"populate_key"} local error_key = {"error_key"} --local function text(tree) return tree[1] end function xtext(tree) if type(tree) == "string" then return tree end -- fast-path some common cases local first = tree[1] if not first then return "" end if type(first) == "string" and not tree[2] then return first end local s = "" for i, lz in xpairs(tree) do s = s..xtext(lz) end return s end function xstring(tree) if type(tree) == "string" then return tree end -- fast-path some common cases local first = tree[1] if not first then return "" end if type(first) == "string" and not tree[2] then return first end local s = "" for i, lz in xpairs(tree) do if type(lz) == "string" then s = s..lz else return nil, "contains mixed content" end end return s end local viewmetatable = {} function viewmetatable.__index(t, k) if not rawget(t, cachecomplete_key) then local populate = t[populate_key] populate(t) end local error_table = rawget(t, error_key) if error_table and error_table[k] then local tablename = t[tree_key].name error("in element "..tablename.." xmlview index "..k..": "..error_table[k]) end return rawget(t, k) end local function ensure_table(t) if type(t) ~= "table" then error("view must be on a table") end end local function populatestringcache(t) local error_table = {} t[error_key] = error_table local root = t[tree_key] for i, element, name in xnpairs(root) do if rawget(t, name) then error_table[name] = "contains duplicate content" else local s, msg = xstring(element) if s then t[name] = xstring(element) else error_table[name] = msg end end end for k,v in pairs(error_table) do t[k] = nil end t[cachecomplete_key] = true end local function string(x) ensure_table(x) local t = {[tree_key]=x, [populate_key]=populatestringcache} setmetatable(t, viewmetatable) return t end Public.string = string local function populatetextcache(t) local error_table = {} t[error_key] = error_table local root = t[tree_key] for i, element, name in xnpairs(root) do if rawget(t, name) then error_table[name] = "contains duplicate content" else t[name] = xtext(element) end end for k,v in pairs(error_table) do t[k] = nil end t[cachecomplete_key] = true end local function text(x) ensure_table(x) local t = {[tree_key]=x, [populate_key]=populatetextcache} setmetatable(t, viewmetatable) return t end Public.text = text local function populatenodecache(t) local error_table = {} t[error_key] = error_table local root = t[tree_key] for i, element, name in xnpairs(root) do if rawget(t, name) then error_table[name] = "contains duplicate content" else t[name] = element end end for k,v in pairs(error_table) do t[k] = nil end t[cachecomplete_key] = true end local function element(x) ensure_table(x) local t = {[tree_key]=x, [populate_key]=populatenodecache} setmetatable(t, viewmetatable) return t end Public.element = element local function populatenodescache(t) local root = t[tree_key] for i, element, name in xnpairs(root) do local existing = rawget(t, name) if not existing then t[name] = {n=0} end table.insert(t[name], element) end t[cachecomplete_key] = true end local function elements(x) ensure_table(x) local t = {[node_key]=x, [populate_key]=populatenodescache} setmetatable(t, viewmetatable) return t end Public.elements = elements