Question

I’ve a bunch of rails app on my server that should be able to use Redis as cache engine.

Do I’ve to start one instance of Redis for each of my application, or does the Redis support scoping?

I’m worried that if I remove one value in one app, the value with the same key will be removed for all of my apps.

I do NOT for example want this to happen.

App 1
Rails.cache.write("key", "value")

App 2
Rails.cache.read("key") => "value"

App 3
Rails.cache.delete("key")

App 1
Rails.cache.read("key") => nil

Answer 1

The solution was to use redis-store with the namespace param.

Here is my config/production.rb file.

# App 1
config.cache_store = :redis_store, {path: "/tmp/redis.sock", db:1, namespace: "app1"}

# App 2
config.cache_store = :redis_store, {path: "/tmp/redis.sock", db:2, namespace: "app2"}