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diff --git a/node_modules/compression/README.md b/node_modules/compression/README.md deleted file mode 100644 index a5d599d..0000000 --- a/node_modules/compression/README.md +++ /dev/null @@ -1,233 +0,0 @@ -# compression - -[![NPM Version][npm-image]][npm-url] -[![NPM Downloads][downloads-image]][downloads-url] -[![Build Status][travis-image]][travis-url] -[![Test Coverage][coveralls-image]][coveralls-url] -[![Gratipay][gratipay-image]][gratipay-url] - -Node.js compression middleware. - -The following compression codings are supported: - - - deflate - - gzip - -## Install - -```bash -$ npm install compression -``` - -## API - -```js -var compression = require('compression') -``` - -### compression([options]) - -Returns the compression middleware using the given `options`. The middleware -will attempt to compress response bodies for all request that traverse through -the middleware, based on the given `options`. - -This middleware will never compress responses that include a `Cache-Control` -header with the [`no-transform` directive](https://tools.ietf.org/html/rfc7234#section-5.2.2.4), -as compressing will transform the body. - -#### Options - -`compression()` accepts these properties in the options object. In addition to -those listed below, [zlib](http://nodejs.org/api/zlib.html) options may be -passed in to the options object. - -##### chunkSize - -The default value is `zlib.Z_DEFAULT_CHUNK`, or `16384`. - -See [Node.js documentation](http://nodejs.org/api/zlib.html#zlib_memory_usage_tuning) -regarding the usage. - -##### filter - -A function to decide if the response should be considered for compression. -This function is called as `filter(req, res)` and is expected to return -`true` to consider the response for compression, or `false` to not compress -the response. - -The default filter function uses the [compressible](https://www.npmjs.com/package/compressible) -module to determine if `res.getHeader('Content-Type')` is compressible. - -##### level - -The level of zlib compression to apply to responses. A higher level will result -in better compression, but will take longer to complete. A lower level will -result in less compression, but will be much faster. - -This is an integer in the range of `0` (no compression) to `9` (maximum -compression). The special value `-1` can be used to mean the "default -compression level", which is a default compromise between speed and -compression (currently equivalent to level 6). - - - `-1` Default compression level (also `zlib.Z_DEFAULT_COMPRESSION`). - - `0` No compression (also `zlib.Z_NO_COMPRESSION`). - - `1` Fastest compression (also `zlib.Z_BEST_SPEED`). - - `2` - - `3` - - `4` - - `5` - - `6` (currently what `zlib.Z_DEFAULT_COMPRESSION` points to). - - `7` - - `8` - - `9` Best compression (also `zlib.Z_BEST_COMPRESSION`). - -The default value is `zlib.Z_DEFAULT_COMPRESSION`, or `-1`. - -**Note** in the list above, `zlib` is from `zlib = require('zlib')`. - -##### memLevel - -This specifies how much memory should be allocated for the internal compression -state and is an integer in the range of `1` (minimum level) and `9` (maximum -level). - -The default value is `zlib.Z_DEFAULT_MEMLEVEL`, or `8`. - -See [Node.js documentation](http://nodejs.org/api/zlib.html#zlib_memory_usage_tuning) -regarding the usage. - -##### strategy - -This is used to tune the compression algorithm. This value only affects the -compression ratio, not the correctness of the compressed output, even if it -is not set appropriately. - - - `zlib.Z_DEFAULT_STRATEGY` Use for normal data. - - `zlib.Z_FILTERED` Use for data produced by a filter (or predictor). - Filtered data consists mostly of small values with a somewhat random - distribution. In this case, the compression algorithm is tuned to - compress them better. The effect is to force more Huffman coding and less - string matching; it is somewhat intermediate between `zlib.Z_DEFAULT_STRATEGY` - and `zlib.Z_HUFFMAN_ONLY`. - - `zlib.Z_FIXED` Use to prevent the use of dynamic Huffman codes, allowing - for a simpler decoder for special applications. - - `zlib.Z_HUFFMAN_ONLY` Use to force Huffman encoding only (no string match). - - `zlib.Z_RLE` Use to limit match distances to one (run-length encoding). - This is designed to be almost as fast as `zlib.Z_HUFFMAN_ONLY`, but give - better compression for PNG image data. - -**Note** in the list above, `zlib` is from `zlib = require('zlib')`. - -##### threshold - -The byte threshold for the response body size before compression is considered -for the response, defaults to `1kb`. This is a number of bytes, any string -accepted by the [bytes](https://www.npmjs.com/package/bytes) module, or `false`. - -**Note** this is only an advisory setting; if the response size cannot be determined -at the time the response headers are written, then it is assumed the response is -_over_ the threshold. To guarantee the response size can be determined, be sure -set a `Content-Length` response header. - -##### windowBits - -The default value is `zlib.Z_DEFAULT_WINDOWBITS`, or `15`. - -See [Node.js documentation](http://nodejs.org/api/zlib.html#zlib_memory_usage_tuning) -regarding the usage. - -#### .filter - -The default `filter` function. This is used to construct a custom filter -function that is an extension of the default function. - -```js -app.use(compression({filter: shouldCompress})) - -function shouldCompress(req, res) { - if (req.headers['x-no-compression']) { - // don't compress responses with this request header - return false - } - - // fallback to standard filter function - return compression.filter(req, res) -} -``` - -### res.flush - -This module adds a `res.flush()` method to force the partially-compressed -response to be flushed to the client. - -## Examples - -### express/connect - -When using this module with express or connect, simply `app.use` the module as -high as you like. Requests that pass through the middleware will be compressed. - -```js -var compression = require('compression') -var express = require('express') - -var app = express() - -// compress all requests -app.use(compression()) - -// add all routes -``` - -### Server-Sent Events - -Because of the nature of compression this module does not work out of the box -with server-sent events. To compress content, a window of the output needs to -be buffered up in order to get good compression. Typically when using server-sent -events, there are certain block of data that need to reach the client. - -You can achieve this by calling `res.flush()` when you need the data written to -actually make it to the client. - -```js -var compression = require('compression') -var express = require('express') - -var app = express() - -// compress responses -app.use(compression()) - -// server-sent event stream -app.get('/events', function (req, res) { - res.setHeader('Content-Type', 'text/event-stream') - res.setHeader('Cache-Control', 'no-cache') - - // send a ping approx every 2 seconds - var timer = setInterval(function () { - res.write('data: ping\n\n') - - // !!! this is the important part - res.flush() - }, 2000) - - res.on('close', function () { - clearInterval(timer) - }) -}) -``` - -## License - -[MIT](LICENSE) - -[npm-image]: https://img.shields.io/npm/v/compression.svg -[npm-url]: https://npmjs.org/package/compression -[travis-image]: https://img.shields.io/travis/expressjs/compression/master.svg -[travis-url]: https://travis-ci.org/expressjs/compression -[coveralls-image]: https://img.shields.io/coveralls/expressjs/compression/master.svg -[coveralls-url]: https://coveralls.io/r/expressjs/compression?branch=master -[downloads-image]: https://img.shields.io/npm/dm/compression.svg -[downloads-url]: https://npmjs.org/package/compression -[gratipay-image]: https://img.shields.io/gratipay/dougwilson.svg -[gratipay-url]: https://www.gratipay.com/dougwilson/ |