Sanitizing and Japanese full/half-width character converting for Node.js

node-ja-sanitize.js

var validator = require('validator');
var hankaku = '1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ ';
var zenkaku = '１２３４５６７８９０ａｂｃｄｅｆｇｈｉｊｋｌｍｎｏｐｑｒｓｔｕｖｗｘｙｚＡＢＣＤＥＦＧＨＩＪＫＬＭＮＯＰＱＲＳＴＵＶＷＸＹＺ　';

var zenkakuToHankaku = function (word) {
  for (var i = 0, n = zenkaku.length; i < n; i++) {
    word = word.replace(new RegExp(zenkaku[i], 'gm'), hankaku[i]);
  }
  return word.replace(/^\s+|\s+$/g, ''); // trim head and tail white space
};
var sanitize = function (param) {
  return function (req, res, next) {
    var map = req[param];
    if (map) {
      for (var key in map) {
        var word = map[key];
        if (typeof word === 'string') {
          map[key] = validator.sanitize(zenkakuToHankaku(word)).xss();
        }
      }
    }
    next();
  };
};
app.get('*', sanitize('query'), function (req, res, next) {
  // do something
  next();
});
app.post('*', sanitize('body'), function (req, res, next) {
  // do something
  next();
});