Add ActiveStorage.service_configurations and ActiveStorage.service

* Allow plugins to access the global service and alternative service configs before ActiveStorage::Blob loads.

* Make ActiveStorage.service_configurations the default second argument to ActiveStorage::Service.configure. Plugins that just want to use an alternative service defined in config/storage.yml needn't pass in the config themselves.

4 files changed, 36 insertions, 30 deletions

diff --git a/activestorage/app/models/active_storage/blob.rb b/activestorage/app/models/active_storage/blob.rb
index c9fbafad1f..4da1605448 100644
--- a/activestorage/app/models/active_storage/blob.rb
+++ b/activestorage/app/models/active_storage/blob.rb
@@ -29,7 +29,7 @@ class ActiveStorage::Blob < ActiveRecord::Base
   has_secure_token :key
   store :metadata, accessors: [ :analyzed, :identified ], coder: ActiveRecord::Coders::JSON
 
-  class_attribute :service
+  class_attribute :service, default: ActiveStorage.service
 
   has_many :attachments
 
diff --git a/activestorage/lib/active_storage.rb b/activestorage/lib/active_storage.rb
index 5c5da551ae..c00c9f8037 100644
--- a/activestorage/lib/active_storage.rb
+++ b/activestorage/lib/active_storage.rb
@@ -41,19 +41,25 @@ module ActiveStorage
   autoload :Previewer
   autoload :Analyzer
 
-  mattr_accessor :logger
-  mattr_accessor :verifier
-  mattr_accessor :queues, default: {}
-  mattr_accessor :previewers, default: []
-  mattr_accessor :analyzers, default: []
+  mattr_accessor :service_configurations, default: {}
+  mattr_accessor :service
+
+  mattr_accessor :queues,            default: {}
+  mattr_accessor :previewers,        default: []
+  mattr_accessor :analyzers,         default: []
   mattr_accessor :variant_processor, default: :mini_magick
-  mattr_accessor :paths, default: {}
-  mattr_accessor :variable_content_types, default: []
+  mattr_accessor :paths,             default: {}
+
+  mattr_accessor :variable_content_types,           default: []
   mattr_accessor :content_types_to_serve_as_binary, default: []
-  mattr_accessor :content_types_allowed_inline, default: []
-  mattr_accessor :binary_content_type, default: "application/octet-stream"
+  mattr_accessor :content_types_allowed_inline,     default: []
+  mattr_accessor :binary_content_type,              default: "application/octet-stream"
+
   mattr_accessor :service_urls_expire_in, default: 5.minutes
-  mattr_accessor :routes_prefix, default: "/rails/active_storage"
+  mattr_accessor :routes_prefix,          default: "/rails/active_storage"
+
+  mattr_accessor :logger
+  mattr_accessor :verifier
 
   module Transformers
     extend ActiveSupport::Autoload
diff --git a/activestorage/lib/active_storage/engine.rb b/activestorage/lib/active_storage/engine.rb
index fc75a8f816..b27a027f3a 100644
--- a/activestorage/lib/active_storage/engine.rb
+++ b/activestorage/lib/active_storage/engine.rb
@@ -95,25 +95,25 @@ module ActiveStorage
     end
 
     initializer "active_storage.services" do
-      ActiveSupport.on_load(:active_storage_blob) do
-        if config_choice = Rails.configuration.active_storage.service
-          configs = Rails.configuration.active_storage.service_configurations ||= begin
-            config_file = Pathname.new(Rails.root.join("config/storage.yml"))
-            raise("Couldn't find Active Storage configuration in #{config_file}") unless config_file.exist?
-
-            require "yaml"
-            require "erb"
-
-            YAML.load(ERB.new(config_file.read).result) || {}
-          rescue Psych::SyntaxError => e
-            raise "YAML syntax error occurred while parsing #{config_file}. " \
-                  "Please note that YAML must be consistently indented using spaces. Tabs are not allowed. " \
-                  "Error: #{e.message}"
-          end
-
-          ActiveStorage::Blob.service =
+      config.after_initialize do |app|
+        ActiveStorage.service_configurations = begin
+          config_file = Pathname.new(Rails.root.join("config/storage.yml"))
+          raise("Couldn't find Active Storage configuration in #{config_file}") unless config_file.exist?
+
+          require "yaml"
+          require "erb"
+
+          YAML.load(ERB.new(config_file.read).result) || {}
+        rescue Psych::SyntaxError => e
+          raise "YAML syntax error occurred while parsing #{config_file}. " \
+                "Please note that YAML must be consistently indented using spaces. Tabs are not allowed. " \
+                "Error: #{e.message}"
+        end
+
+        if global_service_name = app.config.active_storage.service
+          ActiveStorage.service =
             begin
-              ActiveStorage::Service.configure config_choice, configs
+              ActiveStorage::Service.configure(global_service_name)
             rescue => e
               raise e, "Cannot load `Rails.config.active_storage.service`:\n#{e.message}", e.backtrace
             end
diff --git a/activestorage/lib/active_storage/service.rb b/activestorage/lib/active_storage/service.rb
index aac1e62e7f..f0d04153a1 100644
--- a/activestorage/lib/active_storage/service.rb
+++ b/activestorage/lib/active_storage/service.rb
@@ -45,7 +45,7 @@ module ActiveStorage
       # Configure an Active Storage service by name from a set of configurations,
       # typically loaded from a YAML file. The Active Storage engine uses this
       # to set the global Active Storage service when the app boots.
-      def configure(service_name, configurations)
+      def configure(service_name, configurations = ActiveStorage.service_configurations)
         Configurator.build(service_name, configurations)
       end