| /src/cache.js |
|---|
| @@ -0,0 +1,149 @@ |
|---|
| #!/usr/bin/env node |
| |
| /*************************************************************************/ |
| /* Copyright (C) 2017 Wizardry and Steamworks - License: GNU GPLv3 */ |
| /*************************************************************************/ |
| |
| const fs = require('fs'); |
| const stream = require('stream'); |
| const util = require('util'); |
| const tz = require('moment-timezone'); |
| const forge = require('node-forge'); |
| const EventEmitter = require('events').EventEmitter; |
| |
| // Cache constructor. |
| function Cache(config, client, request, response) { |
| // Create events emitters for logging and data. |
| EventEmitter.call(this); |
| |
| // Pass through objects needed for caching. |
| this.config = config; |
| this.client = client; |
| this.request = request; |
| this.response = response; |
| }; |
| |
| // Cache handling. |
| Cache.prototype.process = function(resource, input, type) { |
| EventEmitter.call(this); |
| const self = this; |
| |
| fs.stat(resource, (error, stats) => { |
| var expires = 0; |
| Object.keys(self.config.site.cache).forEach((key) => { |
| self.config.site.cache[key].forEach((expire) => { |
| if (expire.test(resource)) { |
| expires = key; |
| } |
| }); |
| }); |
| |
| switch (self.request.httpVersion) { |
| case '1.1': // HTTP 1.1 |
| self.response.setHeader('Cache-Control', |
| "max-age=" + expires + ", public" |
| ); |
| const sha1 = forge.md.sha1.create(); |
| const data = new stream.Readable({ |
| objectMode: true, |
| read(size) {} |
| }); |
| input |
| .on('data', (chunk) => { |
| sha1.update(chunk); |
| data.push(chunk); |
| }) |
| .on('end', () => { |
| const etag = sha1.digest().toHex(); |
| |
| // Set the ETag for the resource. |
| self.response.setHeader('ETag', etag); |
| |
| const ifNoneMatch = Object |
| .getOwnPropertyNames(self.request.headers) |
| .filter((header) => header.toUpperCase() === |
| 'If-None-Match'.toUpperCase()); |
| |
| const ifModifiedSince = Object |
| .getOwnPropertyNames(self.request.headers) |
| .filter((header) => header.toUpperCase() === |
| 'If-Modified-Since'.toUpperCase()); |
| |
| if ((ifNoneMatch.length !== 0 && |
| self.request.headers[ifNoneMatch].toUpperCase() === etag.toUpperCase()) || |
| (ifModifiedSince.length !== 0 && |
| tz(self.request.headers[ifModifiedSince]).tz('UTC') < tz(stat.mtime).tz('UTC'))) { |
| // Send a cache hit response. |
| self.emit('log', { |
| message: 'Client: ' + |
| self.client.address + ':' + |
| self.client.port + |
| ' cached resource: ' + |
| resource, |
| severity: 'info' |
| }); |
| self.emit('data', { |
| status: 304, |
| data: new stream.Readable({ |
| read(size) { |
| this.push(null); |
| } |
| }), |
| type: type |
| }); |
| return; |
| } |
| |
| // Send the resource. |
| self.emit('log', { |
| message: 'Client: ' + |
| self.client.address + ':' + |
| self.client.port + |
| ' sent resource: ' + |
| resource, |
| severity: 'info' |
| }); |
| data.push(null); |
| self.emit('data', { |
| status: 200, |
| data: data, |
| type: type |
| }); |
| }); |
| |
| return; |
| default: |
| self.response.setHeader('Last-Modified', |
| tz(stats.mtime) |
| .tz('UTC') |
| .format("ddd, DD MMM YYYY HH:mm:ss z") |
| ); |
| self.response.setHeader('Expires', |
| tz() |
| .tz('UTC') |
| .add(expires, 'seconds') |
| .format("ddd, DD MMM YYYY HH:mm:ss z") |
| ); |
| // Send the resource. |
| self.emit('log', { |
| message: 'Client: ' + |
| self.client.address + ':' + |
| self.client.port + |
| ' sent resource: ' + |
| resource, |
| severity: 'info' |
| }); |
| self.emit('data', { |
| status: 200, |
| data: input, |
| type: type |
| }); |
| break; |
| } |
| }); |
| |
| return this; |
| }; |
| |
| util.inherits(Cache, EventEmitter); |
| module.exports = Cache; |
