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diff --git a/middleware/node_modules/iconv-lite/README.md b/middleware/node_modules/iconv-lite/README.md new file mode 100644 index 0000000..c981c37 --- /dev/null +++ b/middleware/node_modules/iconv-lite/README.md @@ -0,0 +1,156 @@ +## Pure JS character encoding conversion [](https://travis-ci.org/ashtuchkin/iconv-lite) + + * Doesn't need native code compilation. Works on Windows and in sandboxed environments like [Cloud9](http://c9.io). + * Used in popular projects like [Express.js (body_parser)](https://github.com/expressjs/body-parser), + [Grunt](http://gruntjs.com/), [Nodemailer](http://www.nodemailer.com/), [Yeoman](http://yeoman.io/) and others. + * Faster than [node-iconv](https://github.com/bnoordhuis/node-iconv) (see below for performance comparison). + * Intuitive encode/decode API + * Streaming support for Node v0.10+ + * [Deprecated] Can extend Node.js primitives (buffers, streams) to support all iconv-lite encodings. + * In-browser usage via [Browserify](https://github.com/substack/node-browserify) (~180k gzip compressed with Buffer shim included). + * Typescript [type definition file](https://github.com/ashtuchkin/iconv-lite/blob/master/lib/index.d.ts) included. + * React Native is supported (need to explicitly `npm install` two more modules: `buffer` and `stream`). + * License: MIT. + +[](https://npmjs.org/packages/iconv-lite/) + +## Usage +### Basic API +```javascript +var iconv = require('iconv-lite'); + +// Convert from an encoded buffer to js string. +str = iconv.decode(Buffer.from([0x68, 0x65, 0x6c, 0x6c, 0x6f]), 'win1251'); + +// Convert from js string to an encoded buffer. +buf = iconv.encode("Sample input string", 'win1251'); + +// Check if encoding is supported +iconv.encodingExists("us-ascii") +``` + +### Streaming API (Node v0.10+) +```javascript + +// Decode stream (from binary 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 + }); +}); +``` + +### [Deprecated] Extend Node.js own encodings +> NOTE: This doesn't work on latest Node versions. See [details](https://github.com/ashtuchkin/iconv-lite/wiki/Node-v4-compatibility). + +```javascript +// After this call all Node basic primitives will understand iconv-lite encodings. +iconv.extendNodeEncodings(); + +// Examples: +buf = new Buffer(str, 'win1251'); +buf.write(str, 'gbk'); +str = buf.toString('latin1'); +assert(Buffer.isEncoding('iso-8859-15')); +Buffer.byteLength(str, 'us-ascii'); + +http.createServer(function(req, res) { + req.setEncoding('big5'); + req.collect(function(err, body) { + console.log(body); + }); +}); + +fs.createReadStream("file.txt", "shift_jis"); + +// External modules are also supported (if they use Node primitives, which they probably do). +request = require('request'); +request({ + url: "http://github.com/", + encoding: "cp932" +}); + +// To remove extensions +iconv.undoExtendNodeEncodings(); +``` + +## 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. + * 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. + +See [all supported encodings on wiki](https://github.com/ashtuchkin/iconv-lite/wiki/Supported-Encodings). + +Most singlebyte encodings are generated automatically from [node-iconv](https://github.com/bnoordhuis/node-iconv). Thank you Ben Noordhuis and libiconv authors! + +Multibyte encodings are generated from [Unicode.org mappings](http://www.unicode.org/Public/MAPPINGS/) and [WHATWG Encoding Standard mappings](http://encoding.spec.whatwg.org/). Thank you, respective authors! + + +## Encoding/decoding speed + +Comparison with node-iconv module (1000x256kb, on MacBook Pro, Core i5/2.6 GHz, Node v0.12.0). +Note: your results may vary, so please always check on your hardware. + + operation iconv@2.1.4 iconv-lite@0.4.7 + ---------------------------------------------------------- + encode('win1251') ~96 Mb/s ~320 Mb/s + decode('win1251') ~95 Mb/s ~246 Mb/s + +## 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](https://github.com/danielgindi/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. + +## Other notes + +When decoding, be sure to supply a Buffer to decode() method, otherwise [bad things usually happen](https://github.com/ashtuchkin/iconv-lite/wiki/Use-Buffers-when-decoding). +Untranslatable characters are set to � or ?. No transliteration is currently supported. +Node versions 0.10.31 and 0.11.13 are buggy, don't use them (see #65, #77). + +## Testing + +```bash +$ git clone git@github.com:ashtuchkin/iconv-lite.git +$ cd iconv-lite +$ npm install +$ npm test + +$ # To view performance: +$ node test/performance.js + +$ # To view test coverage: +$ npm run coverage +$ open coverage/lcov-report/index.html +``` |