libre-service.eu/pad.libre-service.eu-etherpad
libre-service.eu/pad.libre-service.eu-etherpad
1
0
Fork 0
mirror of https://github.com/ether/etherpad-lite.git synced 2025-01-31 19:02:59 +01:00
Code Issues Projects Releases Wiki Activity

CachingMiddleware: Asyncify

Browse source
This commit is contained in:
Richard Hansen 2021-02-27 00:08:29 -05:00 committed by webzwo0i
parent 0284d49522
commit f86df5322e
2 changed files with 99 additions and 112 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
src/node/hooks/express/static.js
View file

@ -31,7 +31,7 @@ const getTar = async () => {
exports.expressCreateServer = async (hookName, args) => {
// Cache both minified and static.
const assetCache = new CachingMiddleware();
args.app.all(/\/javascripts\/(.*)/, assetCache.handle);
args.app.all(/\/javascripts\/(.*)/, assetCache.handle.bind(assetCache));
// Minify will serve static files compressed (minify enabled). It also has
// file-specific hacks for ace/require-kernel/etc.

209
src/node/utils/caching_middleware.js
View file

@ -16,13 +16,14 @@
* limitations under the License.
*/
const async = require('async');
const Buffer = require('buffer').Buffer;
const fs = require('fs');
const fsp = fs.promises;
const path = require('path');
const zlib = require('zlib');
const settings = require('./Settings');
const existsSync = require('./path_exists');
const util = require('util');
/*
* The crypto module can be absent on reduced node installations.
@ -79,6 +80,10 @@ if (_crypto) {
module.exports = class CachingMiddleware {
handle(req, res, next) {
this._handle(req, res, next).catch((err) => next(err || new Error(err)));
}
async _handle(req, res, next) {
if (!(req.method === 'GET' || req.method === 'HEAD') || !CACHE_DIR) {
return next(undefined, req, res);
}
@ -92,125 +97,107 @@ module.exports = class CachingMiddleware {
const url = new URL(req.url, 'http://localhost');
const cacheKey = generateCacheKey(url.pathname + url.search);
fs.stat(`${CACHE_DIR}minified_${cacheKey}`, (error, stats) => {
const modifiedSince = (req.headers['if-modified-since'] &&
new Date(req.headers['if-modified-since']));
const lastModifiedCache = !error && stats.mtime;
if (lastModifiedCache && responseCache[cacheKey]) {
req.headers['if-modified-since'] = lastModifiedCache.toUTCString();
const stats = await fsp.stat(`${CACHE_DIR}minified_${cacheKey}`).catch(() => {});
const modifiedSince =
req.headers['if-modified-since'] && new Date(req.headers['if-modified-since']);
if (stats != null && stats.mtime && responseCache[cacheKey]) {
req.headers['if-modified-since'] = stats.mtime.toUTCString();
} else {
delete req.headers['if-modified-since'];
}
// Always issue get to downstream.
oldReq.method = req.method;
req.method = 'GET';
// This handles read/write synchronization as well as its predecessor,
// which is to say, not at all.
// TODO: Implement locking on write or ditch caching of gzip and use
// existing middlewares.
const respond = () => {
req.method = oldReq.method || req.method;
res.write = oldRes.write || res.write;
res.end = oldRes.end || res.end;
const headers = {};
Object.assign(headers, (responseCache[cacheKey].headers || {}));
const statusCode = responseCache[cacheKey].statusCode;
let pathStr = `${CACHE_DIR}minified_${cacheKey}`;
if (supportsGzip && /application\/javascript/.test(headers['content-type'])) {
pathStr += '.gz';
headers['content-encoding'] = 'gzip';
}
const lastModified = headers['last-modified'] && new Date(headers['last-modified']);
if (statusCode === 200 && lastModified <= modifiedSince) {
res.writeHead(304, headers);
res.end();
} else if (req.method === 'GET') {
const readStream = fs.createReadStream(pathStr);
res.writeHead(statusCode, headers);
readStream.pipe(res);
} else {
delete req.headers['if-modified-since'];
res.writeHead(statusCode, headers);
res.end();
}
};
// Always issue get to downstream.
oldReq.method = req.method;
req.method = 'GET';
const expirationDate = new Date(((responseCache[cacheKey] || {}).headers || {}).expires);
if (expirationDate > new Date()) {
// Our cached version is still valid.
return respond();
}
// This handles read/write synchronization as well as its predecessor,
// which is to say, not at all.
// TODO: Implement locking on write or ditch caching of gzip and use
// existing middlewares.
const respond = () => {
req.method = oldReq.method || req.method;
res.write = oldRes.write || res.write;
res.end = oldRes.end || res.end;
const _headers = {};
oldRes.setHeader = res.setHeader;
res.setHeader = (key, value) => {
// Don't set cookies, see issue #707
if (key.toLowerCase() === 'set-cookie') return;
const headers = {};
Object.assign(headers, (responseCache[cacheKey].headers || {}));
const statusCode = responseCache[cacheKey].statusCode;
_headers[key.toLowerCase()] = value;
oldRes.setHeader.call(res, key, value);
};
let pathStr = `${CACHE_DIR}minified_${cacheKey}`;
if (supportsGzip && /application\/javascript/.test(headers['content-type'])) {
pathStr += '.gz';
headers['content-encoding'] = 'gzip';
}
oldRes.writeHead = res.writeHead;
res.writeHead = (status, headers) => {
res.writeHead = oldRes.writeHead;
if (status === 200) {
// Update cache
let buffer = '';
const lastModified = (headers['last-modified'] &&
new Date(headers['last-modified']));
Object.keys(headers || {}).forEach((key) => {
res.setHeader(key, headers[key]);
});
headers = _headers;
if (statusCode === 200 && lastModified <= modifiedSince) {
res.writeHead(304, headers);
res.end();
} else if (req.method === 'GET') {
const readStream = fs.createReadStream(pathStr);
res.writeHead(statusCode, headers);
readStream.pipe(res);
} else {
res.writeHead(statusCode, headers);
res.end();
}
};
const expirationDate = new Date(((responseCache[cacheKey] || {}).headers || {}).expires);
if (expirationDate > new Date()) {
// Our cached version is still valid.
return respond();
oldRes.write = res.write;
oldRes.end = res.end;
res.write = (data, encoding) => {
buffer += data.toString(encoding);
};
res.end = async (data, encoding) => {
await Promise.all([
fsp.writeFile(`${CACHE_DIR}minified_${cacheKey}`, buffer).catch(() => {}),
util.promisify(zlib.gzip)(buffer)
.then((content) => fsp.writeFile(`${CACHE_DIR}minified_${cacheKey}.gz`, content))
.catch(() => {}),
]);
responseCache[cacheKey] = {statusCode: status, headers};
respond();
};
} else if (status === 304) {
// Nothing new changed from the cached version.
oldRes.write = res.write;
oldRes.end = res.end;
res.write = (data, encoding) => {};
res.end = (data, encoding) => { respond(); };
} else {
res.writeHead(status, headers);
}
};
const _headers = {};
oldRes.setHeader = res.setHeader;
res.setHeader = (key, value) => {
// Don't set cookies, see issue #707
if (key.toLowerCase() === 'set-cookie') return;
_headers[key.toLowerCase()] = value;
oldRes.setHeader.call(res, key, value);
};
oldRes.writeHead = res.writeHead;
res.writeHead = (status, headers) => {
res.writeHead = oldRes.writeHead;
if (status === 200) {
// Update cache
let buffer = '';
Object.keys(headers || {}).forEach((key) => {
res.setHeader(key, headers[key]);
});
headers = _headers;
oldRes.write = res.write;
oldRes.end = res.end;
res.write = (data, encoding) => {
buffer += data.toString(encoding);
};
res.end = (data, encoding) => {
async.parallel([
(callback) => {
const path = `${CACHE_DIR}minified_${cacheKey}`;
fs.writeFile(path, buffer, (error, stats) => {
callback();
});
},
(callback) => {
const path = `${CACHE_DIR}minified_${cacheKey}.gz`;
zlib.gzip(buffer, (error, content) => {
if (error) {
callback();
} else {
fs.writeFile(path, content, (error, stats) => {
callback();
});
}
});
},
], () => {
responseCache[cacheKey] = {statusCode: status, headers};
respond();
});
};
} else if (status === 304) {
// Nothing new changed from the cached version.
oldRes.write = res.write;
oldRes.end = res.end;
res.write = (data, encoding) => {};
res.end = (data, encoding) => { respond(); };
} else {
res.writeHead(status, headers);
}
};
next(undefined, req, res);
});
next(undefined, req, res);
}
};