alexandrule

Ruby: The future of frozen string literals

What is a literal?

In programming languages, literals are textual representations of values in the source code. This is a syntactical concept.

Some examples:

7 # integer literal

alexandrule

JWT Auth + Refresh Tokens in Rails

This is just some code I recently used in my development application in order to add token-based authentication for my api-only rails app. The api-client was to be consumed by a mobile application, so I needed an authentication solution that would keep the user logged in indefinetly and the only way to do this was either using refresh tokens or sliding sessions.

I also needed a way to both blacklist and whitelist tokens based on a unique identifier (jti)

Before trying it out DIY, I considered using:

alexandrule

Based on this blogpost.

Install with Homebrew:

$ brew install postgresql@14

(The version number 14 needs to be explicitly stated. The @ mark designates a version number is specified. If you need an older version of postgres, use postgresql@13, for example.)

alexandrule

Installing pg gem on macOS

If you're trying to install the postgresql gem pg and it is failing with the following error message:

Installing pg 1.2.3 with native extensions
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

    current directory: ~/.rbenv/versions/3.0.0/lib/ruby/gems/3.0.0/gems/pg-1.2.3/ext
~/.rbenv/versions/3.0.0/bin/ruby -I ~/.rbenv/versions/3.0.0/lib/ruby/3.0.0 -r ./siteconf20210125-97201-pycpo.rb extconf.rb

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# /etc/systemd/system/foo.service
[Unit]
Description=Foo service
Wants=nginx.service
Requires=postgresql.service
After=postgresql.service

[Service]
Type=simple
User=foo

alexandrule

FROM ruby:2.3.1

# Install dependencies
RUN apt-get update -qq && apt-get install -y build-essential libpq-dev nodejs

# Set an environment variable where the Rails app is installed to inside of Docker image:
ENV RAILS_ROOT /var/www/app_name
RUN mkdir -p $RAILS_ROOT

# Set working directory, where the commands will be ran:

alexandrule

How to Run a Process in the Background with TMUX

There are times when you need to log off your Linux Desktop, and you want a process to run in the background. TMUX manages this very well.

For this example, let's suppose you're running a long running task like running rspecs on your project and it is 5pm, and you need to go home.

Run Your Process

alexandrule

Deploy Rails Application to AWS EC2

Creating AWS EC2 Instance

- login to 'AWS Management Console' (https://aws.amazon.com/console/)
- from 'Services'(in navbar) choose 'EC2'
- from 'Create Instance' section, click on 'Launch Instance'
- then select 'AMI' (Amazon Machine Image), we will be using 'Ubuntu Server 16.04 LTS (HVM)' as example
- select 'Instance Type' as per your requirement
- then click 'Next:Configure Instance Details' to continue
  change 'Configure Instance Details' or used as default settings

alexandrule

Africa/Abidjan
Africa/Accra
Africa/Addis_Ababa
Africa/Algiers
Africa/Asmara
Africa/Asmera
Africa/Bamako
Africa/Bangui
Africa/Banjul
Africa/Bissau

alexandrule

FROM ruby:2.6.5-alpine

RUN apk add --update --no-cache bash build-base nodejs sqlite-dev tzdata postgresql-dev yarn

RUN gem install bundler:2.1.4

WORKDIR /usr/src/app

COPY package.json yarn.lock ./
RUN yarn install --check-files