Output Lua Table To Html File

wiki

-- dontspamme_samlie@yahoo.com

-- Converts Lua table to HTML output in table.html file
function tohtml(x)
  ret = tohtml_table(x,1)
  writefile("table.html", ret)
  os.execute("table.html")
  return(ret)
end

-- Saves a string to file
function writefile(filename, value)
  if (value) then
    local file = io.open(filename,"w+")
    file:write(value)
    file:close()
  end
end

-- Flattens a table to html output
function tohtml_table(x, table_level)
  local k, s,  tcolor
  local html_colors = {
    "#339900","#33CC00","#669900","#666600","#FF3300",
    "#FFCC00","#FFFF00","#CCFFCC","#CCCCFF","#CC66FF",
    "#339900","#33CC00","#669900","#666600","#FF3300",
    "#FFCC00","#FFFF00","#CCFFCC","#CCCCFF","#CC66FF"
  }
  local lineout = {}
  local tablefound = false
    if type(x) == "table" then
    s = ""
    k = 1
    local i, v = next(x)
    while i do
      if (type(v) == "table") then
        if (table_level<10) then
          lineout[k] =  "<b>" .. flat(i) .. "</b>".. tohtml_table(v, table_level + 1)   
        else
          lineout[k] = "<b>MAXIMUM LEVEL BREACHED</b>"
        end
        tablefound = true
      else
        lineout[k] = flat(i) .. "=" .. tohtml_table(v)
      end
      k = k + 1
      i, v = next(x, i)
    end

    for k,line in ipairs(lineout) do
      if (tablefound) then
        s = s .. "<tr><td>" .. line .. "</td></tr>\n"
      else
        s = s .. "<td>" .. line .. "</td>\n"
      end
    end
    if not (tablefound) then
      s = "<table border='1' bgcolor='#FFFFCC' cellpadding='5' cellspacing='0'>" ..
        "<tr>" .. s .. "</tr></table>\n"
    else
      tcolor = html_colors[table_level]
      s = "<table border='3' bgcolor='"..tcolor.."' cellpadding='10' cellspacing='0'>" ..
          s ..  "</table>\n"
    end

    return s 
  end
  if type(x) == "function" then
    return "FUNC"
  end
  if type(x) == "file" then
    return "FILE"
  end

  return tostring(x) 
end

-- Flattens a table to string
function flat(x)  
  return toflat(x,1)
end

-- Flattens a table to string
function toflat(x, tlevel)
  local s
  tlevel = tlevel + 1

  if type(x) == "table" then
    s = "{"
    local i, v = next(x)
    while i do
      if (tlevel < 15) then
        s = s .. i .. "=" .. toflat(v, tlevel) 
      else
        s = s .. i .. "={#}" 
      end

      i, v = next(x, i)
      if i then
        s = s .. ", " 
      end
    end
    return s .. "}\n"
  end
  if type(x) == "function" then
    return "FUNC"
  end
  if type(x) == "file" then
    return "FILE"
  end

  return tostring(x) 
end

Take #2

Here is a more advanced implementation, with expand/collapsing and handling cycles. (See warning in comments before use.)

-- Example dumping Lua tables to HTML for debugging.
--
-- Warning: not complete or well tested.  This is only intended
-- as an example/starting point.  Clean it up if used in production.
--
-- (c) 2008 David Manura (2008-12)
-- Licensed under the same terms as Lua (MIT license).

local coroutine = coroutine
local next = next
local pairs = pairs
local string = string
local tostring = tostring
local type = type
local _G = _G

local format = string.format


-- Escape string to make suitable for embedding in HTML.
local function htmlize(s)
  s = s:gsub('&', '&')
  s = s:gsub('<', '&lt;')
  s = s:gsub('>', '&gt;')
  return s
end


-- iterator function for table pairs.
-- hash part, then array part.
-- used for display.
local function table_pairs(t)
  local keys = {}
  for k in pairs(t) do keys[#keys+1] = k end
  table.sort(keys, function(a,b)
    if type(a) == 'number' and type(b) == 'string' then
      return false
    elseif type(a) == 'string' and type(b) == 'number' then
      return true
    else
      return a < b
    end
  end)
  local i = 0
  return function()
    i = i + 1
    local k = keys[i]
    if k then return k, t[k] end
  end
end


-- Serialize object o.  Writes one or more substrings to function append.
local function obj_serialize(o, append)
  if type(o) == 'table' then
    append('{')
    for k,v in table_pairs(o) do
      append('[')
      obj_serialize(k, append)
      append(']=[')
      obj_serialize(v, append)
      append('];')
    end
    append('}')
  elseif type(o) == 'string' then
    append(string.format('%q', o))
  else
    append(tostring(o))
  end
end


-- Returns serialization of o, not exceeding maxlen characters.
local function obj_tostring_short(o, maxlen)
  local s = ''
  local function append(ss)
    s = s .. ss
    if #s > maxlen then
      s = s:sub(1,maxlen) .. '...'
      coroutine.yield()
    end
  end
  local f = coroutine.wrap(obj_serialize)
  f(o, append)
  return s
end


local function analyze_tree(o)
  local ids = {}
  local current_id = 0
  local count = {}
  local from = {}

  local function analyze_tree_helper(o)
    if type(o) == 'table' then
      if count[o] then
        count[o] = count[o] + 1
      else
        count[o] = 1
        current_id = current_id + 1
        ids[o] = current_id
  
        local this_id = current_id
        for k,v in pairs(o) do
          analyze_tree_helper(k)
          analyze_tree_helper(v)
          if type(k) == 'table' then
            from[k] = from[k] or {}; from[k][o] = this_id .. '.' .. ids[k]
          end
          if type(v) == 'table' then
            from[v] = from[v] or {};
            from[v][o] = this_id .. '.' .. (ids[k] or tostring(k))
          end
        end
      end
    end
  end
  analyze_tree_helper(o)

  for k,v in pairs(count) do
    if v == 1 then count[k] = nil end
  end

  return ids, count, from
end


local header = [[
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<title>FIX</title>
<style type="text/css">
.table {margin-left:1em; border: 1px solid black}
.table_row {border: 1px solid black}
</style>
<script type="text/javascript"><!--
function toggle(id) {
  if (document.getElementById) {
    var ele = document.getElementById(id);
    if (ele && ele.style) {
      ele.style.display = ele.style.display == 'none' ? '' : 'none';
    }
  }
}
function show_node(ele) {
  if (ele.style) {
    ele.style.display = '';
    if (ele.parentNode) show_node(ele.parentNode);
  }
}
function show(id) {
  if (document.getElementById) {
    var ele = document.getElementById(id);
    if (ele) show_node(ele);
  }
}
//--></script>
</head>
<body>
]]
local footer = [[</body></html>]]


-- Writes HTML representations of object o as one or more strings to
-- function output.
local function object_to_html(o, output)
  local ids, count, from = analyze_tree(o)

  local output_html

  local function output_header_html(o)
    if type(o) == 'table' then
      output(format('<a name="id%s"></a>', ids[o]))

      local is_empty = next(o) == nil
      output(is_empty and '(empty)' or
             '<a href="javascript:toggle(\'id' .. ids[o] .. '\')">[+]</a>')
      output(format([[Table ID %s]], ids[o]))
      output(type(o.tag) == 'string' and ' [Tag=' .. o.tag .. ']' or '')
      output(' ')
      output(htmlize(obj_tostring_short(o, 40)))
    elseif type(o) == 'string' then
      output(htmlize(string.format('%q', o)))
    else
      output(htmlize(tostring(o)))
    end  
  end

  local function output_body_html(o)
    if type(o) == 'table' then
      output(format('<div class="table" style="display:none" id="id%s">\n', ids[o]))

      -- xref
      if from[o] and next(from[o]) and next(from[o], next(from[o])) then
        output('<div>Referenced from: ')
        for _,from_id in pairs(from[o]) do
          output(format([[ <a onclick="show('id%s')" href="#id%s">%s</a> ]],
                 from_id, from_id, from_id))
        end
        output('</div>')
      end

      -- key/values
      for k,v in table_pairs(o) do
        local function prepare_output(oo)
          local f, is_long
          if count[oo] then
            f = function()
              output(format([[<a onclick="show('id%s')" href="#id%s">(see %s)</a>]],
                            ids[oo],ids[oo],ids[oo]))
            end
          elseif type(oo) ~= 'table' then
            f = function() output_header_html(oo) end
          else
            f = function() output_header_html(oo) end
            is_long = true
          end
          return f, is_long
        end
        local kf, klong = prepare_output(k)
        local vf, vlong = prepare_output(v)

        local field_id = ids[o] .. '.' .. (ids[k] or tostring(k))
        output(format([[<a name="id%s"></a>]], field_id))

        output(format('<div class="table_row" id="id%s">\n', field_id))
        kf()
        output('=')
        vf()
        if vlong then output_body_html(v) end
        output('</div>')
      end

      output('</div>\n')

    end
  end

  --local
  function output_html(o)
    output('<div>')
    output_header_html(o)
    output('</div>')
    output_body_html(o)
  end

  output(header)

  output_html(o)
  for oo in pairs(count) do
    if oo ~= o then
      output_html(oo)
    end
  end

  output(footer)
end


-- example usage

local function dump(obj)
  object_to_html(obj, function(s) io.stdout:write(s) end)
end

dump(_G)

-- metalua example
--[[
package.path = package.path .. ';/luaanalyze/lib/?.lua'
require "lexer"
require "gg"
require "mlp_lexer"
require "mlp_misc"
require "mlp_table"
require "mlp_meta"
require "mlp_expr"
require "mlp_stat"
require "mlp_ext"
mlc = {} -- make gg happy
local mlp = assert(_G.mlp)
local function string_to_ast(src, filename)
  filename = filename or '(string)'
  local  lx  = mlp.lexer:newstream (src, filename)
  local  ast = mlp.chunk(lx)
  return ast
end
local src_file = assert(io.open ('mydump.lua', 'r'))
local src = src_file:read '*a'; src_file:close()
local ast = string_to_ast(src, src_filename)
local function remove_lineinfo(o)
  if type(o) == 'table' then
    o.lineinfo = nil
    for k,v in pairs(o) do
      remove_lineinfo(k)
      remove_lineinfo(v)
    end
  end
end
remove_lineinfo(ast)
dump(ast)
--]]

See Also

• TableSerialization - Recursive table print/serialization