Trigger listeners only for enabled plugin

Previously any plugin that would subscribe to notifications would be
always triggered, which made it impossible to isolate plugin configs

lib/rom/components/core.rb

@@ -72,7 +72,7 @@ def adapter
         )
       end
 
-      # @api public
+      # @api private
       def apply_plugins
         plugins.each do |plugin|
           plugin.apply_to(constant)

lib/rom/configuration.rb

@@ -53,29 +53,20 @@ def initialize(*args, &block)
       configure(*args, &block)
     end
 
-    # @api public
+    # This is called internally when you pass a block to ROM.container
+    #
+    # @api private
     def configure(*args)
-      unless args.empty?
-        gateways_config = args.first.is_a?(Hash) ? args.first : {default: args}
-
-        gateways_config.each do |name, value|
-          args = Array(value)
-
-          adapter, *rest = args
-
-          if rest.size > 1 && rest.last.is_a?(Hash)
-            load_config(config.gateways[name], {adapter: adapter, args: rest[0..-1], **rest.last})
-          else
-            options = rest.first.is_a?(Hash) ? rest.first : {args: rest.flatten(1)}
-            load_config(config.gateways[name], {adapter: adapter, **options})
-          end
-        end
-      end
+      infer_config(*args) unless args.empty?
 
       # Load adapters explicitly here to ensure their plugins are present already
       # while setup loads components and then triggers finalization
       setup.load_adapters
 
+      # TODO: this is tricky because if you want to tweak the config in the block
+      #       you end up doing `config.config.foo = "bar"` so it would be good
+      #       to yield configuration object + its config or rename this whole class
+      #       because it's a configuration *DSL* that builds up a config object too
       yield(self) if block_given?
 
       # No more changes allowed
@@ -89,10 +80,30 @@ def configure(*args)
 
     # @api private
     def finalize
+      attach_listeners
       setup.finalize
       self
     end
 
+    # @api private
+    def attach_listeners
+      # Anything can attach globally to certain events, including plugins, so here
+      # we're making sure that only plugins that are enabled in thi configuration
+      # will be
+      global_listeners = Notifications.listeners.to_a
+        .reject { |(src, *)| plugin_registry.mods.include?(src) }.to_h
+
+      plugin_listeners = Notifications.listeners.to_a
+        .select { |(src, *)| plugins.map(&:mod).include?(src) }.to_h
+
+      listeners.update(global_listeners).update(plugin_listeners)
+    end
+
+    # @api private
+    def listeners
+      notifications.listeners
+    end
+
     # Apply a plugin to the configuration
     #
     # @param [Mixed] plugin The plugin identifier, usually a Symbol
@@ -156,6 +167,27 @@ def respond_to_missing?(name, include_all = false)
 
     private
 
+    # This infers config based on arguments passed to either ROM.container
+    # or Configuration.ne
+    #
+    # @api private
+    def infer_config(*args)
+      gateways_config = args.first.is_a?(Hash) ? args.first : {default: args}
+
+      gateways_config.each do |name, value|
+        args = Array(value)
+
+        adapter, *rest = args
+
+        if rest.size > 1 && rest.last.is_a?(Hash)
+          load_config(config.gateways[name], {adapter: adapter, args: rest[0..-1], **rest.last})
+        else
+          options = rest.first.is_a?(Hash) ? rest.first : {args: rest.flatten(1)}
+          load_config(config.gateways[name], {adapter: adapter, **options})
+        end
+      end
+    end
+
     # @api private
     def load_config(config, hash)
       hash.each do |key, value|

lib/rom/plugin_registry.rb

@@ -12,9 +12,13 @@ class PluginRegistry
     # @api private
     attr_reader :types
 
+    # @api private
+    attr_reader :mods
+
     # @api private
     def initialize
       @types = ::Concurrent::Map.new
+      @mods = []
     end
 
     # Register a plugin for future use
@@ -27,6 +31,7 @@ def initialize
     # @option options [Symbol] :adapter (:default) which adapter this plugin
     # applies to. Leave blank for all adapters
     def register(name, mod, options = EMPTY_HASH)
+      mods << mod
       type(options.fetch(:type)).register(name, mod, options)
     end
 

lib/rom/support/notifications.rb

@@ -54,7 +54,7 @@ module Publisher
       #
       # @api public
       def subscribe(event_id, query = EMPTY_HASH, &block)
-        listeners[event_id] << [block, query]
+        listeners[self] << [event_id, block, query]
         self
       end
 
@@ -67,7 +67,11 @@ def subscribe(event_id, query = EMPTY_HASH, &block)
       def trigger(event_id, payload = EMPTY_HASH)
         event = events[event_id]
 
-        listeners[event.id].each do |(listener, query)|
+        event_listeners = listeners.values.flatten(1).group_by(&:first)
+
+        return unless event_listeners.key?(event_id)
+
+        event_listeners[event_id].each do |(_, listener, query)|
           event.payload(payload).trigger(listener, query)
         end
       end
@@ -178,7 +182,7 @@ def self.listeners
     #
     # @api public
     def self.event_bus(id)
-      EventBus.new(id, events: events.dup, listeners: listeners.dup)
+      EventBus.new(id, events: events.dup)
     end
 
     # Extension for objects that can listen to events
@@ -193,7 +197,7 @@ module Listener
       #
       # @api public
       def subscribe(event_id, query = EMPTY_HASH, &block)
-        Notifications.listeners[event_id] << [block, query]
+        Notifications.listeners[self] << [event_id, block, query]
       end
     end
 
@@ -224,9 +228,9 @@ class EventBus
       # @param [Hash] listeners A hash with listeners
       #
       # @api public
-      def initialize(id, events: EMPTY_HASH, listeners: LISTENERS_HASH.dup)
+      def initialize(id, events: EMPTY_HASH)
         @id = id
-        @listeners = listeners
+        @listeners = LISTENERS_HASH.dup
         @events = events
       end
     end

spec/shared/changeset/database.rb

@@ -15,7 +15,11 @@
 RSpec.shared_context "changeset / database setup" do
   include_context "changeset / db_uri"
 
-  let(:configuration) { ROM::Configuration.new(:sql, db_uri) }
+  let(:configuration) do
+    ROM::Configuration.new(:sql, db_uri) do |config|
+      config.plugin(:sql, relation: :auto_restrictions)
+    end
+  end
 
   let(:conn) { configuration.gateways[:default].connection }
 

spec/shared/repository/database.rb

@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require "rom/sql"
 RSpec.shared_context "repository / db_uri" do
   let(:base_db_uri) do
     ENV.fetch("BASE_DB_URI", "postgres@localhost/rom")
@@ -14,7 +15,9 @@
   include_context "repository / db_uri"
 
   let(:configuration) do
-    ROM::Configuration.new(:sql, db_uri)
+    ROM::Configuration.new(:sql, db_uri) do |config|
+      config.plugin(:sql, relation: :auto_restrictions)
+    end
   end
 
   let(:conn) do