Use Redis as caching mechanism

Gemfile

@@ -3,7 +3,7 @@ ruby "2.5.1"
 
 gem "active_model_serializers"
 gem "bunny"
-gem "delayed_job_active_record"
+gem "delayed_job_active_record" # TODO: Get off of SQL backed jobs. Use Redis
 gem "delayed_job"
 gem "devise"
 gem "discard"
@@ -31,7 +31,7 @@ gem "webpack-rails"
 # Still working out the bugs. - RC 5 Jul 18
 gem "rabbitmq_http_api_client"
 gem "zero_downtime_migrations"
-# gem "digest-murmurhash"
+gem "redis", "~> 4.0"
 
 group :development, :test do
   gem "thin"

Gemfile.lock

@@ -262,6 +262,7 @@ GEM
       rake (>= 0.8.7)
       thor (>= 0.19.0, < 2.0)
     rake (12.3.1)
+    redis (4.0.2)
     representable (3.0.4)
       declarative (< 0.1.0)
       declarative-option (< 0.2.0)
@@ -389,6 +390,7 @@ DEPENDENCIES
   rails
   rails-erd
   rails_12factor
+  redis (~> 4.0)
   request_store
   rollbar
   rspec
@@ -409,4 +411,4 @@ RUBY VERSION
    ruby 2.5.1p57
 
 BUNDLED WITH
-   1.16.2
+   1.16.5

app/lib/rmq_config_writer.rb

@@ -25,6 +25,8 @@ class RmqConfigWriter
                     "using 3rd party MQTT hosting, please set this value and "\
                     "re-build the server image."
   TEMPLATE        = <<~END
+    # THIS FILE WAS GENERATED BY THE `RmqConfigWriter` CLASS IN THE RAILS APP
+    # == DO NOT ATTEMPT TO MODIFY MANUALLY - IT WILL BE OVERWRITTEN ===
     auth_backends.1                 = cache
     auth_cache.cache_ttl            = 600000
     auth_cache.cached_backend       = http
@@ -41,7 +43,6 @@ class RmqConfigWriter
   END
 
   def self.do_render
-    puts "Writing RMQ Config ================================================="
     raise BAD_PASSWORD if ADMIN_PASSWORD.length < 5
     FileUtils.mkdir_p CONFIG_PATH
     File.open(CONFIG_OUTPUT, "w+") { |f| f.write(TEMPLATE % CFG_DATA) }

config/application.rb

@@ -9,12 +9,11 @@ Bundler.require(:default, Rails.env)
 module FarmBot
   class Application < Rails::Application
     Delayed::Worker.max_attempts = 4
-    # config.after_initialize do
-    #   Bullet.enable  = true
-    #   Bullet.console = true
-    # end
+    REDIS_ENV_KEY = ENV.fetch("WHERE_IS_REDIS_URL", "REDIS_URL")
+    REDIS_URL     = ENV.fetch(REDIS_ENV_KEY, "redis://redis:6379/0")
+    config.cache_store                 = :redis_cache_store, { url: REDIS_URL }
     config.active_record.schema_format = :sql
-    config.active_job.queue_adapter = :delayed_job
+    config.active_job.queue_adapter    = :delayed_job
     config.action_dispatch.perform_deep_munge = false
     I18n.enforce_available_locales = false
     LOCAL_API_HOST = ENV["API_HOST"] || "localhost"

config/environments/production.rb

@@ -1,10 +1,10 @@
 FarmBot::Application.configure do
+
   config
     .action_mailer
     .default_url_options = { host: ENV.fetch("API_HOST", "my.farmbot.io") }
   config.active_support.deprecation  = :notify
   config.cache_classes               = true
-  config.cache_store                 = :null_store
   config.consider_all_requests_local = false
   config.eager_load                  = true
   config.force_ssl                   = true if ENV["FORCE_SSL"]

config/initializers/config_writers.rb

@@ -0,0 +1,4 @@
+# Some services do not use ENV vars as the configuration mechanism (I wish they
+# would). To simplify setup for self-hosters, we perform magic in the background
+# that converts ENV vars into config files. - RC
+RmqConfigWriter.render

config/initializers/rmq_config.rb

@@ -1,2 +0,0 @@
-
-RmqConfigWriter.render

docker-compose.yml

@@ -1,6 +1,6 @@
 version: '3.4'
 x-db_user: &db_user
-  depends_on: ["db"]
+  depends_on: ["db", "redis"]
 x-rails: &rails
   image:    farmbot_web
   env_file: .env
@@ -9,9 +9,11 @@ x-rails: &rails
     - ./docker_volumes/bundle_cache:/bundle
 services:
   redis:
-    image: redis:4.0.11
-    environment: ["REDIS_PASS=mypass"]
-    ports:       ["6379:6379"]
+    image: redis
+    volumes:
+     - ./docker_volumes/redis/data:/data
+     - ./docker_volumes/redis/conf:/usr/local/etc/redis
+    ports: ["6379:6379"]
   db:          # ====================
     image: postgres
     volumes: ["./docker_volumes/db:/var/lib/postgresql/data"]

example.env

@@ -63,7 +63,14 @@ FORCE_SSL=Remove this if not using HTTPS://
 # If running a FarmBot setup for personal use or none of the above apply, you
 # can safely delete the rest of this file.
 
-
+# Only relevant if you use Heroku or pay a 3rd party vendor for Redis hosting.
+# Most users can delete this.
+# If your Heroku Redis vendor uses a custom `REDIS_URL` ENV var such as
+# `REDISTOGO_URL`, set the value here. If you  delete this line, the app will
+# default to `REDIS_URL`.
+WHERE_IS_REDIS_URL=REDISTOGO_URL # Just an example. Change or delete.
+# Delete this if you  don't use 3rd party Redis hosting. See WHERE_IS_REDIS_URL
+REDIS_URL=redis://redis:6379/0
 
 # For email delivery. Who is your email host?
 SMTP_HOST=smtp.sendgrid.net