#56 Redis Basics

Summary

Redis within a Ruby on Rails application has many benefits. Learn to interact with Redis Server and set it up for caching within your application.
rails cache performance 5:42

Resources

Summary

# MacOS Terminal
brew install redis
brew services start redis

# Ubuntu Terminal
sudo apt install redis-server

# irb
2.3.3 :001 > require 'redis'
 => true

2.3.3 :002 > redis = Redis.new
 => #

2.3.3 :003 > redis.set 'key', 'value'
 => "OK"

2.3.3 :004 > redis.get 'key'
 => "value"

Using Redis as a cache

# Gemfile
gem 'redis-rails'

# config/environments/development.rb
  config.cache_store = :redis_store, {
    host: 'localhost',
    port: 6379,
    db: 0,
    namespace: '056redis'
  }

You will also need to configure the production environment file with the Redis cache. Instead of specifying the values within each configuration file, I recommend using the secrets.yml file instead. For example, 

# config/environments/development.rb
  config.cache_store = :redis_store, {
    host: Rails.application.secrets.redis_server,
    port: Rails.application.secrets.redis_port,
    db: Rails.application.secrets.redis_cache_database,
    namespace: Rails.application.secrets.redis_cache_namespace
  }

# secrets.yml
development:
  secret_key_base: ...
  redis_server: localhost
  redis_port: 6379
  redis_cache_database: 0
  redis_cache_namespace: '056redis'

# index.html
<% cache 'word-of-the-hour', expires_in: Time.now.beginning_of_hour + 1.hour do %>
  <%= %w(happy developer watch drifting ruby screencasts about rails).sample %>
<% end %>