xprezzo-iconv: Pure JS character encoding conversion

• Intuitive character encode/decode API, including Streaming support.

Usage

Basic API

const iconv = require("xprezzo-iconv")

// Convert from an encoded buffer to a js string.
str = iconv.decode(Buffer.from([0x68, 0x65, 0x6c, 0x6c, 0x6f]), "win1251")

// Convert from a js string to an encoded buffer.
buf = iconv.encode("Sample input string", "win1251")

// Check if encoding is supported
iconv.encodingExists("us-ascii")

Streaming API

// Decode stream (from binary data stream to js strings)
http.createServer(function (req, res) {
    var converterStream = iconv.decodeStream("win1251")
    req.pipe(converterStream)

    converterStream.on("data", function (str) {
        console.log(str); // Do something with decoded strings, chunk-by-chunk.
    })
})

// Convert encoding streaming example
fs.createReadStream("file-in-win1251.txt")
    .pipe(iconv.decodeStream("win1251"))
    .pipe(iconv.encodeStream("ucs2"))
    .pipe(fs.createWriteStream("file-in-ucs2.txt"))

// Sugar: all encode/decode streams have .collect(cb) method to accumulate data.
http.createServer(function (req, res) {
    req.pipe(iconv.decodeStream("win1251")).collect(function (err, body) {
        assert(typeof body == "string")
        console.log(body) // full request body string
    });
});

Supported encodings

• All node.js native encodings: utf8, ucs2 / utf16-le, ascii, binary, base64, hex.
• Additional unicode encodings: utf16, utf16-be, utf-7, utf-7-imap, utf32, utf32-le, and utf32-be.
• All widespread singlebyte encodings: Windows 125x family, ISO-8859 family, IBM/DOS codepages, Macintosh family, KOI8 family, all others supported by iconv library. Aliases like 'latin1', 'us-ascii' also supported.
• All widespread multibyte encodings: CP932, CP936, CP949, CP950, GB2312, GBK, GB18030, Big5, Shift_JIS, EUC-JP.

BOM handling

• Decoding: BOM is stripped by default, unless overridden by passing stripBOM: false in options (f.ex. iconv.decode(buf, enc, {stripBOM: false})). A callback might also be given as a stripBOM parameter - it'll be called if BOM character was actually found.
• If you want to detect UTF-8 BOM when decoding other encodings, use node-autodetect-decoder-stream module.
• Encoding: No BOM added, unless overridden by addBOM: true option.

UTF-16 Encodings

This library supports UTF-16LE, UTF-16BE and UTF-16 encodings. First two are straightforward, but UTF-16 is trying to be smart about endianness in the following ways:

• Decoding: uses BOM and 'spaces heuristic' to determine input endianness. Default is UTF-16LE, but can be overridden with defaultEncoding: 'utf-16be' option. Strips BOM unless stripBOM: false.
• Encoding: uses UTF-16LE and writes BOM by default. Use addBOM: false to override.

UTF-32 Encodings

This library supports UTF-32LE, UTF-32BE and UTF-32 encodings. Like the UTF-16 encoding above, UTF-32 defaults to UTF-32LE, but uses BOM and 'spaces heuristics' to determine input endianness.

• The default of UTF-32LE can be overridden with the defaultEncoding: 'utf-32be' option. Strips BOM unless stripBOM: false.
• Encoding: uses UTF-32LE and writes BOM by default. Use addBOM: false to override. (defaultEncoding: 'utf-32be' can also be used here to change encoding.)

Testing

$ git clone [email protected]:xprezzo/xprezzo-iconv.git
$ cd xprezzo-iconv
$ npm install
$ npm run test

$ # To view performance:
$ node test/performance.js

$ # To view test coverage:
$ npm run test-cov

People

Xprezzo and related projects are maintained by Cloudgen Wong](mailto:[email protected]).

License

MIT