plugins/mod_http_errors.lua

   1 module:set_global();
   2
   3 local server = require "net.http.server";
   4 local codes = require "net.http.codes";
   5 local termcolours = require "util.termcolours";
   6
   7 local show_private = module:get_option_boolean("http_errors_detailed", false);
   8 local always_serve = module:get_option_boolean("http_errors_always_show", true);
   9 local default_message = { module:get_option_string("http_errors_default_message", "That's all I know.") };
  10 local default_messages = {
  11         [400] = { "What kind of request do you call that??" };
  12         [403] = { "You're not allowed to do that." };
  13         [404] = { "Whatever you were looking for is not here. %";
  14                 "Where did you put it?", "It's behind you.", "Keep looking." };
  15         [500] = { "% Check your error log for more info.";
  16                 "Gremlins.", "It broke.", "Don't look at me." };
  17 };
  18
  19 local messages = setmetatable(module:get_option("http_errors_messages", {}), { __index = default_messages });
  20
  21 local html = [[
  22 <!DOCTYPE html>
  23 <html>
  24 <head>
  25         <meta charset="utf-8">
  26         <style>
  27                 body{
  28                         margin-top:14%;
  29                         text-align:center;
  30                         background-color:#F8F8F8;
  31                         font-family:sans-serif;
  32                 }
  33                 h1{
  34                         font-size:xx-large;
  35                 }
  36                 p{
  37                         font-size:x-large;
  38                 }
  39                 p+p { font-size: large; font-family: courier }
  40         </style>
  41 </head>
  42 <body>
  43         <h1>$title</h1>
  44         <p>$message</p>
  45         <p>$extra</p>
  46 </body>
  47 </html>]];
  48 html = html:gsub("%s%s+", "");
  49
  50 local entities = {
  51         ["<"] = "&lt;", [">"] = "&gt;", ["&"] = "&amp;",
  52         ["'"] = "&apos;", ["\""] = "&quot;", ["\n"] = "<br/>",
  53 };
  54
  55 local function tohtml(plain)
  56         return (plain:gsub("[<>&'\"\n]", entities));
  57
  58 end
  59
  60 local function get_page(code, extra)
  61         local message = messages[code];
  62         if always_serve or message then
  63                 message = message or default_message;
  64                 return (html:gsub("$(%a+)", {
  65                         title = rawget(codes, code) or ("Code "..tostring(code));
  66                         message = message[1]:gsub("%%", function ()
  67                                 return message[math.random(2, math.max(#message,2))];
  68                         end);
  69                         extra = tohtml(extra or "");
  70                 }));
  71         end
  72 end
  73
  74 module:hook_object_event(server, "http-error", function (event)
  75         return get_page(event.code, (show_private and event.private_message) or event.message);
  76 end);