Decouple Command from Relation

Gemfile

@@ -12,13 +12,9 @@ if ENV["USE_DRY_INITIALIZER_MASTER"].eql?("true")
   gem "dry-initializer", github: "dry-rb/dry-initializer", branch: "master"
 end
 
-if ENV["USE_ROM_SQL_MASTER"].eql?("true")
-  gem "rom-sql", github: "rom-rb/rom-sql", branch: "master"
-else
-  gem "rom-sql", "~> 3.3", ">= 3.3.1"
-end
-
 group :sql do
+  gem "rom-sql", github: "rom-rb/rom-sql", branch: "decouple-commands-from-relations"
+  # TODO: >= 5.32.0 breaks mysql schema inference in some cases
   gem "dry-monitor"
   gem "jdbc-postgres", platforms: :jruby
   gem "jdbc-sqlite3", platforms: :jruby

lib/rom/command.rb

@@ -194,18 +194,22 @@ class Command
 
     # @!attribute [r] relation
     #   @return [Relation] Command's relation
-    param :relation
+    param :dataset
 
     CommandType = Types::Strict::Symbol.enum(:create, :update, :delete)
     Result = Types::Strict::Symbol.enum(:one, :many)
 
+    # @!attribute [r] schema
+    #   @return [Schema] Relation's schema
+    option :schema, optional: true
+
     # @!attribute [r] type
     #   @return [Symbol] The command type, one of :create, :update or :delete
     option :type, type: CommandType, optional: true
 
     # @!attribute [r] source
-    #   @return [Relation] The source relation
-    option :source, default: -> { relation }
+    #   @return [Dataset] The source dataset
+    option :source, default: -> { dataset }
 
     # @!attribute [r] result
     #   @return [Symbol] Result type, either :one or :many
@@ -227,26 +231,18 @@ class Command
     #   @return [Array<Hash>] An array with after hooks configuration
     option :after, Types::Coercible::Array, reader: false, default: -> { self.class.after }
 
-    input Hash
-    result :many
-
-    # Return name of this command's relation
-    #
-    # @return [ROM::Relation::Name]
-    #
+    # !@attribute :name
+    # @return [ROM::Relation::Name] Return name of this command's relation
     # @api public
-    def name
-      relation.name
-    end
+    option :name, optional: true
 
-    # Return gateway of this command's relation
-    #
-    # @return [Symbol]
-    #
+    # !@attribute :gateway
+    # @return [Symbol] Return gateway of this command's relation
     # @api public
-    def gateway
-      relation.gateway
-    end
+    option :gateway, optional: true
+
+    input Hash
+    result :many
 
     # Execute the command
     #
@@ -314,7 +310,7 @@ def curry(*args)
       if curry_args.empty? && args.first.is_a?(Graph::InputEvaluator)
         Lazy[self].new(self, *args)
       else
-        self.class.build(relation, **options, curry_args: args)
+        self.class.build(dataset, **options, curry_args: args)
       end
     end
 
@@ -346,7 +342,7 @@ def curried?
     #
     # @api public
     def before(*hooks)
-      self.class.new(relation, **options, before: before_hooks + hooks)
+      self.class.new(dataset, **options, before: before_hooks + hooks)
     end
 
     # Return a new command with appended after hooks
@@ -357,7 +353,7 @@ def before(*hooks)
     #
     # @api public
     def after(*hooks)
-      self.class.new(relation, **options, after: after_hooks + hooks)
+      self.class.new(dataset, **options, after: after_hooks + hooks)
     end
 
     # List of before hooks
@@ -378,15 +374,15 @@ def after_hooks
       options[:after]
     end
 
-    # Return a new command with other source relation
+    # Return a new command with other source dataset
     #
-    # This can be used to restrict command with a specific relation
+    # This can be used to restrict command with a specific dataset
     #
     # @return [Command]
     #
     # @api public
-    def new(new_relation)
-      self.class.build(new_relation, **options, source: relation)
+    def new(new_dataset)
+      self.class.build(new_dataset, **options, source: dataset)
     end
 
     # Check if this command has any hooks
@@ -432,22 +428,13 @@ def many?
       result.equal?(:many)
     end
 
-    # Check if this command is restrictible through relation
-    #
-    # @return [TrueClass,FalseClass]
-    #
-    # @api private
-    def restrictible?
-      self.class.restrictable.equal?(true)
-    end
-
     # Yields tuples for insertion or return an enumerator
     #
     # @api private
     def map_input_tuples(tuples, &mapper)
       return enum_for(:with_input_tuples, tuples) unless mapper
 
-      if tuples.respond_to? :merge
+      if tuples.respond_to?(:merge)
         mapper[tuples]
       else
         tuples.map(&mapper)

lib/rom/command_compiler.rb

@@ -217,9 +217,9 @@ def register_command(rel_name, type, rel_meta, parent_relation = nil)
           command: klass, gateway: gateway, dataset: relation.dataset, adapter: adapter
         )
 
-        klass.extend_for_relation(relation) if klass.restrictable
+        command_input = meta[:input] || relation.input_schema
 
-        registry[rel_name][type] = klass.build(relation)
+        registry[rel_name][type] = klass.build(relation.dataset, input: command_input)
       end
     end
 

lib/rom/commands/class_interface.rb

@@ -71,8 +71,8 @@ def adapter_namespace(adapter)
       # @return [Command]
       #
       # @api public
-      def build(relation, **options)
-        new(relation, **self.options, **options)
+      def build(dataset, **options)
+        new(dataset, **self.options, **options)
       end
 
       # Create a command class with a specific type

lib/rom/core.rb

@@ -25,9 +25,9 @@
 # container factory
 require "rom/create_container"
 
-# register known plugin types
 require "rom/schema_plugin"
 
+# register known plugin types
 ROM::Plugins.register(:command)
 ROM::Plugins.register(:mapper)
 ROM::Plugins.register(:relation)
@@ -37,7 +37,6 @@
 # register core plugins
 require "rom/plugins/relation/registry_reader"
 require "rom/plugins/relation/instrumentation"
-require "rom/plugins/command/schema"
 require "rom/plugins/command/timestamps"
 require "rom/plugins/schema/timestamps"
 
@@ -48,7 +47,6 @@ module ROM
     register :timestamps, ROM::Plugins::Schema::Timestamps, type: :schema
     register :registry_reader, ROM::Plugins::Relation::RegistryReader, type: :relation
     register :instrumentation, ROM::Plugins::Relation::Instrumentation, type: :relation
-    register :schema, ROM::Plugins::Command::Schema, type: :command
     register :timestamps, ROM::Plugins::Command::Timestamps, type: :command
   end
 end

lib/rom/memory/commands.rb

@@ -13,13 +13,12 @@ module Commands
       # @api public
       class Create < ROM::Commands::Create
         adapter :memory
-        use :schema
 
         # @see ROM::Commands::Create#execute
         def execute(tuples)
           Array([tuples]).flatten.map { |tuple|
             attributes = input[tuple]
-            relation.insert(attributes.to_h)
+            dataset.insert(attributes.to_h)
             attributes
           }.to_a
         end
@@ -30,12 +29,11 @@ def execute(tuples)
       # @api public
       class Update < ROM::Commands::Update
         adapter :memory
-        use :schema
 
         # @see ROM::Commands::Update#execute
         def execute(params)
           attributes = input[params]
-          relation.map { |tuple| tuple.update(attributes.to_h) }
+          dataset.map { |tuple| tuple.update(attributes.to_h) }
         end
       end
 
@@ -47,7 +45,7 @@ class Delete < ROM::Commands::Delete
 
         # @see ROM::Commands::Delete#execute
         def execute
-          relation.to_a.map do |tuple|
+          dataset.to_a.map do |tuple|
             source.delete(tuple)
             tuple
           end

lib/rom/relation/commands.rb

@@ -54,11 +54,7 @@ def command(type, mapper: nil, use: EMPTY_ARRAY, plugins_options: EMPTY_HASH, **
             base_command
           end
 
-        if command.restrictible?
-          command.new(self)
-        else
-          command
-        end
+        command.new(dataset)
       end
     end
   end

lib/rom/setup/finalize/finalize_commands.rb

@@ -39,9 +39,12 @@ def run!
             command: klass, gateway: gateway, dataset: relation.dataset, adapter: relation.adapter
           )
 
-          klass.extend_for_relation(relation) if klass.restrictable
-
-          klass.build(relation)
+          klass.build(
+            relation.dataset,
+            input: relation.input_schema,
+            name: relation.name,
+            gateway: relation.gateway
+          )
         end
 
         registry = Registry.new
@@ -54,7 +57,7 @@ def run!
         )
 
         @relations.each do |(name, relation)|
-          rel_commands = commands.select { |c| c.relation.name == relation.name }
+          rel_commands = commands.select { |c| c.dataset.eql?(relation.dataset) }
 
           rel_commands.each do |command|
             identifier = command.class.register_as || command.class.default_name

spec/spec_helper.rb

@@ -20,6 +20,7 @@
 
 require "rom/core"
 require "rom-changeset"
+require "byebug"
 
 Dir[root.join("support/**/*.rb").to_s].each do |f|
   require f unless f.include?("coverage")

spec/unit/rom/commands/lazy_spec.rb

@@ -142,7 +142,7 @@ def associate(tuple, user)
         ROM::Commands::Lazy[update_task].new(
           update_task,
           evaluator,
-          -> cmd, user, task { cmd.by_user(user[:name]).by_title(task[:title]) }
+          -> cmd, user, task { relation.by_user(user[:name]).by_title(task[:title]).command(:update) }
         )
       end