Skip to content

Commit

Permalink
fix: Replace buffer calls with non-deprecated variants
Browse files Browse the repository at this point in the history
  • Loading branch information
@Alorel
Alorel committed Nov 21, 2018
1 parent c479d5c commit a913591
Show file tree
Hide file tree
Showing 2 changed files with 191 additions and 187 deletions.
114 changes: 59 additions & 55 deletions index.js
View file
Original file line number Diff line number Diff line change
Expand Up @@ -44,6 +44,10 @@ const cacheControlNoTransformRegExp = /(?:^|,)\s*?no-transform\s*?(?:,|$)/;
// worry about compression runtime being slower than gzip
const BROTLI_DEFAULT_QUALITY = 4;

function stubTrue() {
return true;
}

/**
* Compress response data with gzip / deflate.
*
Expand All @@ -54,18 +58,18 @@ const BROTLI_DEFAULT_QUALITY = 4;

function compression(options) {
const opts = options || {};

// options
const filter = opts.filter || shouldCompress;
let threshold = bytes.parse(opts.threshold);

if (threshold === null) {
threshold = 1024;
}

const brotliOpts = opts.brotli || {};
brotliOpts.quality = brotliOpts.quality || BROTLI_DEFAULT_QUALITY;

const zlibOpts = opts.zlib || {};
const zlibOptNames = ['flush', 'chunkSize', 'windowBits', 'level', 'memLevel', 'strategy', 'dictionary'];
zlibOptNames.forEach(function (option) {
Expand All @@ -75,7 +79,7 @@ function compression(options) {
if (!opts.hasOwnProperty('cacheSize')) opts.cacheSize = '128mB';
const cache = opts.cacheSize ? createCache(bytes(opts.cacheSize.toString())) : null;

const shouldCache = opts.cache || function () { return true; };
const shouldCache = opts.cache || stubTrue;

return function compression(req, res, next) {
let ended = false;
Expand All @@ -93,109 +97,109 @@ function compression(options) {
stream.flush();
}
};

// proxy

res.write = function write(chunk, encoding) {
if (ended) {
return false;
}

if (!this._header) {
this._implicitHeader();
}

return stream
? stream.write(new Buffer(chunk, encoding))
? stream.write(Buffer.from(chunk, encoding))
: _write.call(this, chunk, encoding);
};

res.end = function end(chunk, encoding) {
if (ended) {
return false;
}

if (!this._header) {
// estimate the length
if (!this.getHeader('Content-Length')) {
length = chunkLength(chunk, encoding);
}

this._implicitHeader();
}

if (!stream) {
return _end.call(this, chunk, encoding);
}

// mark ended
ended = true;

// write Buffer for Node.js 0.8
return chunk
? stream.end(new Buffer(chunk, encoding))
? stream.end(Buffer.from(chunk, encoding))
: stream.end();
};

res.on = function on(type, listener) {
if (!listeners || type !== 'drain') {
return _on.call(this, type, listener);
}

if (stream) {
return stream.on(type, listener);
}

// buffer listeners for future stream
listeners.push([type, listener]);

return this;
};

function nocompress(msg) {
debug('no compression: %s', msg);
addListeners(res, _on, listeners);
listeners = null;
}

onHeaders(res, function onResponseHeaders() {
// determine if request is filtered
if (!filter(req, res)) {
nocompress('filtered');
return;
}

// determine if the entity should be transformed
if (!shouldTransform(req, res)) {
nocompress('no transform');
return;
}

// vary
vary(res, 'Accept-Encoding');

// content-length below threshold
if (Number(res.getHeader('Content-Length')) < threshold || length < threshold) {
nocompress('size below threshold');
return;
}

const encoding = res.getHeader('Content-Encoding') || 'identity';

// already encoded
if (encoding !== 'identity') {
nocompress('already encoded');
return;
}

// head
if (req.method === 'HEAD') {
nocompress('HEAD request');
return;
}

const contentType = res.getHeader('Content-Type');

// compression method
const accept = accepts(req);
// send in each compression method separately to ignore client preference and
Expand All @@ -206,13 +210,13 @@ function compression(options) {
accept.encoding('gzip') ||
accept.encoding('deflate') ||
accept.encoding('identity');

// negotiation failed
if (!method || method === 'identity') {
nocompress('not acceptable');
return;
}

// do we have this coding/url/etag combo in the cache?
const etag = res.getHeader('ETag') || null;
const cacheable = cache && shouldCache(req, res) && etag && res.statusCode >= 200 && res.statusCode < 300;
Expand All @@ -224,7 +228,7 @@ function compression(options) {
stream = new BufferDuplex(buffer);
}
}

// if stream is not assigned, we got a cache miss and need to compress
// the result
if (!stream) {
Expand All @@ -241,7 +245,7 @@ function compression(options) {
stream = zlib.createDeflate(zlibOpts);
break;
}

// if it is cacheable, let's keep hold of the compressed chunks and cache
// them once the compression stream ends.
if (cacheable) {
Expand All @@ -254,30 +258,30 @@ function compression(options) {
});
}
}

// add buffered listeners to stream
addListeners(stream, stream.on, listeners);

// header fields
res.setHeader('Content-Encoding', method);
res.removeHeader('Content-Length');

// compression
stream.on('data', function onStreamData(chunk) {
if (_write.call(res, chunk) === false) {
stream.pause();
}
});

stream.on('end', function onStreamEnd() {
_end.call(res);
});

_on.call(res, 'drain', function onResponseDrain() {
stream.resume();
});
});

next();
};
}
Expand All @@ -301,7 +305,7 @@ function chunkLength(chunk, encoding) {
if (!chunk) {
return 0;
}

return !Buffer.isBuffer(chunk)
? Buffer.byteLength(chunk, encoding)
: chunk.length;
Expand All @@ -314,12 +318,12 @@ function chunkLength(chunk, encoding) {

function shouldCompress(req, res) {
const type = res.getHeader('Content-Type');

if (type === undefined || !compressible(type)) {
debug('%s not compressible', type);
return false;
}

return true;
}

Expand All @@ -330,7 +334,7 @@ function shouldCompress(req, res) {

function shouldTransform(req, res) {
const cacheControl = res.getHeader('Cache-Control');

// Don't compress for Cache-Control: no-transform
// https://tools.ietf.org/html/rfc7234#section-5.2.2.4
return !cacheControl ||
Expand All @@ -350,44 +354,44 @@ function createCache(size) {
dispose: function (key, item) {
// remove this particular representation (by etag)
delete index[item.coding][item.url][item.etag];

// if there are no more representations of the url left, remove the
// entry for the url.
if (Object.keys(index[item.coding][item.url]).length === 0) {
delete index[item.coding][item.url];
}
}
});

return {
add: function (coding, url, etag, buffer) {
// check to see if another request already filled the cache; avoids
// a lot of work if there's a thundering herd.
if (index[coding] && index[coding][url] && index[coding][url][etag]) {
return;
}

if (Array.isArray(buffer)) {
buffer = Buffer.concat(buffer);
}

const item = {
coding: coding,
url: url,
etag: etag,
buffer: buffer
};
const key = {};

index[coding] = index[coding] || {};
index[coding][url] = index[coding][url] || {};
index[coding][url][etag] = key;

lru.set(key, item);

// now asynchronously re-encode the entry at best quality
const result = new BufferWritable();

new BufferReadable(buffer)
.pipe(getBestQualityReencoder(coding))
.pipe(result)
Expand All @@ -398,7 +402,7 @@ function createCache(size) {
}
});
},

lookup: function (coding, url, etag) {
if (index[coding] && index[coding][url] && index[coding][url][etag]) {
return lru.get(index[coding][url][etag]).buffer;
Expand Down Expand Up @@ -455,7 +459,7 @@ BufferDuplex.prototype._read = function (size) {
this.push(null);
return;
}

const endIndex = Math.min(this.cursor + size, this.buffer.length);
this.push(this.buffer.slice(this.cursor, endIndex));
this.cursor = endIndex;
Expand Down

0 comments on commit a913591

Please sign in to comment.