kredis VS Redis

This is where Kredis, a Redis client for Ruby, comes into play, offering a powerful and efficient caching solution.

# Use the Puma web server [https://github.com/puma/puma] gem "puma", "~> 5.0" # Build JSON APIs with ease [https://github.com/rails/jbuilder] # gem "jbuilder" gem 'rack-cors' gem "devise" gem "jsonapi-serializer" gem 'devise-jwt' gem 'active_model_serializers' gem 'followability' gem 'dotenv-rails', groups: [:development, :test, :production] gem 'sprockets' # Use Redis adapter to run Action Cable in production # gem "redis", "~> 4.0" # Use Kredis to get higher-level data types in Redis [https://github.com/rails/kredis] # gem "kredis" # Use Active Model has_secure_password [https://guides.rubyonrails.org/active_model_basics.html#securepassword] # gem "bcrypt", "~> 3.1.7" # Windows does not include zoneinfo files, so bundle the tzinfo-data gem gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ] # Reduces boot times through caching; required in config/boot.rb gem "bootsnap", require: false # Use Active Storage variants [https://guides.rubyonrails.org/active_storage_overview.html#transforming-images] # gem "image_processing", "~> 1.2" # Use Rack CORS for handling Cross-Origin Resource Sharing (CORS), making cross-origin AJAX possible # gem "rack-cors" group :development, :test do # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem gem "debug", platforms: %i[ mri mingw x64_mingw ] end group :development do gem "sqlite3", "~> 1.4" # Speed up commands on slow machines / big apps [https://github.com/rails/spring] # gem "spring" end group :production do gem 'pg' end

Now the connection is complete, back to our use case where we want to save the onboarded status for each user. We will use kredis in this case to make our life easier by connecting redis database to the application model. Open the user model app/models/user.rb and then add the kredis_boolean attribute because the type we need is a boolean.

In rate_limited? the method request_counter is called which brings us to the part where Kredis is used. We use Kredis to initialize a counter in Redis. Kredis 'instantiates' the value from Redis. In other words, when you call Kredis.counter("mykey") we have an object that points to a Redis value under mykey. On that object we can call #increment which increments the current value in Redis. As you can see we check if the Redis key exists so that we can decide to use the call with expires_in. Each time you call #counter with expires_in, the expire timer resets. We don't want that because then the key will never expire. Checkout the Kredis docs for more information about Kredis.

Let's anwser those questions by making a simple live counter with Turbo Streams and Kredis.

Would Kredis be helpful?

Didn't know about `kredis_hash` I didn't look too hard at the gem when it was announced. Looks like there's more too, how convenient: https://github.com/rails/kredis/blob/main/lib/kredis/attributes.rb

Kredis is a new gem that makes it easier to work with Redis keys in Ruby on Rails. Kredis was added a suggested gem for new Rails applications starting with the release of Rails 7.0 in December of 2021 and is likely to become a larger force in the Rails world in the coming years.

kredis readme

Redis

Redis - real time data storage with different data structures in a cache

[0] https://github.com/redis/redis/blob/unstable/CONTRIBUTING.md

Cache: a Redis cache

I'm curious about something: I suppose Salvatore still owns the copyright for most of the code? The old license does include his copyright, up to 2020: https://github.com/redis/redis/blob/7.2/COPYING So I think this change couldn't have been done without his explicit consent? Or did he transferred his rights to RedisLabs or a foundation?