From fa7ad2a24d808dd6f9c2126598def157431611d4 Mon Sep 17 00:00:00 2001
From: Chung Leong <chernyshevsky@hotmail.com>
Date: Fri, 21 Dec 2018 22:53:16 +0100
Subject: [PATCH] Added Docker and Nginx configs.

---
 server/docker-compose.yml |  51 +++++++++
 server/index.js           | 217 ++++++++++++++++++++++++++++++++++++++
 server/nginx/caching.conf |  14 +++
 server/nginx/default.conf |  44 ++++++++
 4 files changed, 326 insertions(+)
 create mode 100644 server/docker-compose.yml
 create mode 100644 server/index.js
 create mode 100644 server/nginx/caching.conf
 create mode 100644 server/nginx/default.conf

diff --git a/server/docker-compose.yml b/server/docker-compose.yml
new file mode 100644
index 0000000..cb9148b
--- /dev/null
+++ b/server/docker-compose.yml
@@ -0,0 +1,51 @@
+version: "2"
+services:
+  db:
+    image: mysql:5.7
+    ports:
+      - 3306:3306
+    volumes:
+      - db_data:/var/lib/mysql
+    environment:
+      MYSQL_ROOT_PASSWORD: somewordpress
+      MYSQL_DATABASE: wordpress
+      MYSQL_USER: wordpress
+      MYSQL_PASSWORD: wordpress
+    restart: always
+  wordpress:
+    depends_on:
+      - db
+    image: wordpress:latest
+    ports:
+      - 8888:80
+    environment:
+      WORDPRESS_DB_HOST: db:3306
+      WORDPRESS_DB_USER: wordpress
+      WORDPRESS_DB_PASSWORD: wordpress
+    restart: always
+  node:
+    image: node:8
+    ports:
+      - 8080:80
+    volumes:
+      - ..:/opt/example
+      - ./cache:/var/cache/nginx
+    command: [ node, /opt/example/server/index.js ]
+    environment:
+      WORDPRESS_HOST: wordpress
+      NGINX_HOST: nginx
+      NGINX_CACHE: /var/cache/nginx/data
+    restart: always
+  nginx:
+    depends_on:
+      - wordpress
+      - node
+    image: nginx:latest
+    volumes:
+      - ./nginx:/etc/nginx/conf.d
+      - ./cache:/var/cache/nginx
+    ports:
+      - "8000:80"
+    restart: always
+volumes:
+    db_data:
diff --git a/server/index.js b/server/index.js
new file mode 100644
index 0000000..c1be98f
--- /dev/null
+++ b/server/index.js
@@ -0,0 +1,217 @@
+const FS = require('fs');
+const OS = require('os');
+const Express = require('express');
+const CrossFetch = require('cross-fetch');
+const DNSCache = require('dnscache');
+const Crypto = require('crypto');
+const SpiderDetector = require('spider-detector')
+const ReactDOMServer = require('react-dom/server');
+const ClientApp = require('./client/app');
+
+// enable DNS caching
+let dnsCache = DNSCache({ enable: true, ttl: 300, cachesize: 100 });
+
+const basePath = `/`;
+const perPage = 10;
+const serverPort = 80;
+const wordpressHost = process.env.WORDPRESS_HOST;
+const nginxHost = process.env.NGINX_HOST;
+const nginxCache = process.env.NGINX_CACHE;
+
+let wordpressIP;
+dnsCache.lookup(wordpressHost, (err, result) => {
+    if (!err) {
+        wordpressIP = `::ffff:${result}`;
+    }
+});
+
+let app = Express();
+app.set('json spaces', 2);
+app.use(SpiderDetector.middleware());
+app.use(`/`, Express.static(`${__dirname}/www`));
+app.get('/.mtime', handleTimestampRequest);
+app.get(`/*`, handlePageRequest);
+app.purge(`/*`, handlePurgeRequest);
+app.use(handleError);
+app.listen(serverPort);
+
+async function handlePageRequest(req, res, next) {
+    try {
+        let host = `http://${nginxHost}`;
+        let path = req.url;
+        let noScript = (req.query.js === '0')
+        let target = (req.isSpider() || noScript) ? 'seo' : 'hydrate';
+        let sourceURLs = [];
+        // create a fetch() that remembers the URLs used
+        let fetch = (url, options) => {
+            console.log(`Fetching: ${url}`);
+            if (url.startsWith(host)) {
+                var relURL = url.substr(host.length);
+                sourceURLs.push(relURL);
+            }
+            return CrossFetch(url, options);
+        };
+        let options = { host, path, target, fetch };
+        let rootNode = await ClientApp.render(options);
+        let appHTML = ReactDOMServer.renderToString(rootNode);
+        let indexHTMLPath = `${__dirname}/client/index.html`;
+        let html = await replaceHTMLComment(indexHTMLPath, 'APP', appHTML);
+
+        if (target === 'hydrate') {
+            // add <noscript> tag to redirect to SEO version
+            let meta = `<meta http-equiv=refresh content="0; url=?js=0">`;
+            html += `<noscript>${meta}</noscript>`;
+        } else if (target === 'seo') {
+            res.set({ 'X-Accel-Expires': 0 });
+        }
+        res.type('html').send(html);
+
+        recordDependencies(path, sourceURLs);
+    } catch (err) {
+        next(err);
+    }
+}
+
+function handleTimestampRequest(req, res, next) {
+    try {
+        let now = new Date;
+        let ts = now.toISOString();
+        res.type('text').send(ts);
+
+        let path = req.url;
+        recordDependencies(path, '*');
+    } catch (err) {
+        next(err);
+    }
+}
+
+function handleError(err, req, res, next) {
+    if (!res.headersSent) {
+        res.type('text').status(400).send(err.message);
+    } else {
+        console.error(err);
+    }
+}
+
+async function handlePurgeRequest(req, res) {
+    let remoteIP = req.connection.remoteAddress;
+    if (remoteIP === wordpressIP) {
+        let url = req.url;
+        let method = req.headers['x-purge-method'];
+        await purgeCachedFile(url, method);
+
+        let pattern = (method === 'regex') ? new RegExp(url) : url;
+        let isJSON;
+        if (pattern instanceof RegExp) {
+            isJSON = pattern.test('/wp-json');
+        } else {
+            isJSON = pattern.startsWith('/wp-json');
+        }
+        if (isJSON) {
+            await purgeDependentPages(pattern);
+        }
+    }
+    res.end();
+}
+
+let pageDependencies = {};
+
+function recordDependencies(url, sourceURLs) {
+    if (sourceURLs instanceof Array) {
+        sourceURLs = sourceURLs.map(removeTrailingSlash);
+    }
+    pageDependencies[url] = sourceURLs;
+}
+
+async function purgeDependentPages(host, pattern) {
+    for (let [ url, sourceURLs ] of Object.entries(pageDependencies)) {
+        let match = false;
+        if (sourceURLs === '*') {
+            match = true;
+        } else if (pattern instanceof RegExp) {
+            match = sourceURLs.some((sourceURL) => {
+                return pattern.test(sourceURL);
+            });
+        } else {
+            let url = removeTrailingSlash(pattern);
+            if (sourceURLs.indexOf(url)) {
+                match = true;
+            }
+        }
+        if (match) {
+            delete pageDependencies[pageURL];
+            await purgeCachedFile(pageURL);
+        }
+    }
+}
+
+async function purgeCachedFile(url, method) {
+    console.log(`Purging: ${url}`);
+    if (method === 'regex') {
+        // delete everything
+        let files = await new Promise((resolve, reject) => {
+            FS.readdir(nginxCache, (err, files) => {
+                if (!err) {
+                    resolve(files);
+                } else {
+                    resolve([]);
+                }
+            });
+        });
+        let isMD5 = /^[0-9a-f]{32}$/;
+        for (let file of files) {
+            if (isMD5.test(file)) {
+                await unlinkFile(`${nginxCache}/${file}`);
+            }
+        }
+    } else {
+        let hash = Crypto.createHash('md5').update(url);
+        let md5 = hash.digest("hex");
+        await unlinkFile(`${nginxCache}/${md5}`);
+    }
+}
+
+async function unlinkFile(path) {
+    console.log(`Unlinking ${path}`);
+    await new Promise((resolve, reject) => {
+        FS.unlink(path, (err) => {
+            if (!err) {
+                resolve(true);
+            } else {
+                resolve(false);
+            }
+        });
+    });
+}
+
+async function replaceHTMLComment(path, comment, newElement) {
+    let text = await new Promise((resolve, reject) => {
+        FS.readFile(path, 'utf-8', (err, text) => {
+            if (!err) {
+                resolve(text);
+            } else {
+                reject(err);
+            }
+        });
+    });
+    return text.replace(`<!--${comment}-->`, newElement).replace(`<!--${comment}-->`, newElement);
+}
+
+/**
+ * Remove trailing slash from URL
+ *
+ * @param  {String} url
+ *
+ * @return {String}
+ */
+function removeTrailingSlash(url) {
+    var lc = url.charAt(url.length - 1);
+    if (lc === '/') {
+        url = url.substr(0, url.length - 1);
+    }
+    return url;
+}
+
+process.on('unhandledRejection', (err) => {
+    console.error(err);
+});
diff --git a/server/nginx/caching.conf b/server/nginx/caching.conf
new file mode 100644
index 0000000..468c72c
--- /dev/null
+++ b/server/nginx/caching.conf
@@ -0,0 +1,14 @@
+proxy_buffering on;
+proxy_cache data;
+proxy_cache_key $uri$is_args$args;
+proxy_cache_min_uses 1;
+proxy_cache_valid 200 301 302 120m;
+proxy_cache_valid 404 1m;
+proxy_hide_header Cache-Control;
+proxy_hide_header Expires;
+proxy_hide_header Set-Cookie;
+proxy_ignore_headers Cache-Control Expires Set-Cookie;
+
+add_header Cache-Control "public,must-revalidate";
+add_header X-Cache-Date $upstream_http_date;
+add_header X-Cache-Status $upstream_cache_status;
diff --git a/server/nginx/default.conf b/server/nginx/default.conf
new file mode 100644
index 0000000..7b93cce
--- /dev/null
+++ b/server/nginx/default.conf
@@ -0,0 +1,44 @@
+gzip on;
+gzip_disable "msie6";
+
+gzip_vary on;
+gzip_proxied any;
+gzip_comp_level 6;
+gzip_buffers 16 8k;
+gzip_http_version 1.1;
+gzip_types text/plain text/css application/json application/javascript application/x-javascript text/xml application/xml application/xml+rss text/javascript image/svg+xml;
+gzip_min_length 256;
+
+proxy_cache_path /var/cache/nginx/data keys_zone=data:10m max_size=1g;
+proxy_temp_path /var/cache/nginx/tmp;
+
+server {
+    listen 80;
+    server_name _;
+
+    location ~ ^/wp-json/wp/v2/(categories) {
+        proxy_pass http://wordpress;
+        proxy_set_header Host $http_host;
+        include /etc/nginx/conf.d/caching.conf;
+    }
+
+    location ~ ^/wp-.* {
+        proxy_pass http://wordpress;
+        proxy_set_header Host $http_host;
+    }
+
+    location / {
+        proxy_pass http://node;
+        proxy_set_header Host $http_host;
+        include /etc/nginx/conf.d/caching.conf;
+    }
+}
+
+
+upstream node {
+    server node:80;
+}
+
+upstream wordpress {
+    server wordpress:80;
+}