holmberd

In production, it is recommended to minify any JavaScript code that is included with your application. Minification can help your website load several times faster, especially as the size of your JavaScript source code grows.

Here's one way to set it up:

1. Install Node.js
2. Run npm init -y in your project folder (don't skip this step!)
3. Run npm install terser

Now, to minify a file called like_button.js, run in the terminal:

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/** Quick and dirty Cart pub/sub example */

class CartStore {
  add(item) {}
  remove(index) {}
  update(index, item) {}
  get(index) {}
  getAll() {}
}

holmberd

Setup Automatic Security Updates On Ubuntu

Install unattended-upgrade pkg

• (Might already be installed depending on your Ubuntu release)

sudo apt update
sudo apt install unattended-upgrades

Configure unattended-upgrade for security updates only

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/**
 * Retries a async function recursively n times.
 *
 * @param {function} fn
 * @param {Number} [retries=3]
 * @returns {Promise}
 */
function retry(fn, retries=3, err=null) {
  if (retries === 0) {
    return Promise.reject(err);

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Move Redis data to new EBS volume (/mnt/data-01)

• sudo vim /etc/systemd/system/redis.service
  

• Set ReadWriteDirectories=-/mnt/data-01

• sudo mkdir /mnt/data-01/redis

• Set chown and chmod
  The permissons on /var/lib/redis are 755 and it's owned by redis:redis.
  The permissons on /var/lib/redis/dump.rdb are 644 and it's owned by redis:redis.

• Switch configurations while redis is running

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Move MySQL data to new EBS volume (/mnt/data-01)

• mysql -u root -p
• mysql> select @@datadir;
• sudo service mysql stop
• sudo service mysql status
• Move files: sudo rsync -av /var/lib/mysql /mnt/data-01
• Create backup: sudo mv /var/lib/mysql /var/lib/mysql.bak
• Change datadir to point to the new volume:
  • sudo vim /etc/mysql/mysql.conf.d/mysqld.cnf
• datadir=/mnt/data-01/mysql

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Debug Nginx access log

log_format debug_format '$remote_addr - $remote_user [$time_local] "$request" $status $body_bytes_sent "$http_referer" "$http_user_agent" "$http_x_forwarded_for" host:"$host"';
access_log /var/log/nginx/access.log debug_format;

sudo service nginx reload

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Kill user tty/pts sessions in Linux

Commands

• w: show who is logged on and what they are doing
• who: show who is logged on
• tty: show current users pseudo terminal
• ps -ft pts/1: get process id for the pseudo terminal
• pkill: signal process based on name and other attributes

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Responses

POST /api/v1/products

success-status: 201

failure-status: 400 (bad request), 500

{
  id: 1,

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/**
 * Binds a component to one or more decorator functions.
 * @param {Object} component
 * @param {[function]} decorators
 * @returns {Object}
 * @throws {Error}
 */
function Decorator(component, decorators) {
  if (!component || !decorators) {
    throw new Error('Failed to create decorator, arguments invalid.');