var iconv, inherits = require('util').inherits, stream = require('stream'); var regex = /(?:charset|encoding)\s*=\s*['"]? *([\w\-]+)/i; inherits(StreamDecoder, stream.Transform); function StreamDecoder(charset) { if (!(this instanceof StreamDecoder)) return new StreamDecoder(charset); stream.Transform.call(this, charset); this.charset = charset; this.parsed_chunk = false; } StreamDecoder.prototype._transform = function(chunk, encoding, done) { var res, found; // try get charset from chunk, just once if (this.charset == 'utf8' && !this.parsed_chunk) { this.parsed_chunk = true; var matches = regex.exec(chunk.toString()); if (matches) { found = matches[1].toLowerCase(); this.charset = found == 'utf-8' ? 'utf8' : found; } } try { res = iconv.decode(chunk, this.charset); } catch(e) { // something went wrong, just return original chunk res = chunk; } this.push(res); done(); } module.exports = function(charset) { try { if (!iconv) iconv = require('iconv-lite'); } catch(e) { /* iconv not found */ } if (iconv) return new StreamDecoder(charset); else return new stream.PassThrough; }