fix(control_system): should only remove modules only in system [PPT-1…

…102] (#238)

spec/control_system_spec.cr

@@ -48,6 +48,35 @@ module PlaceOS::Model
       driver.destroy
     end
 
+    it "removes modules only when there is a single instance of it remaining" do
+      device_driver = Generator.driver(role: Driver::Role::Device)
+      device_mod2 = Generator.module(driver: device_driver).save!
+      device_mod = Generator.module(driver: device_driver).save!
+
+      control_system = Generator.control_system
+      control_system.modules = [device_mod.id.as(String), device_mod2.id.as(String)]
+      control_system.save!
+
+      driver = Generator.driver(role: Driver::Role::Logic)
+      mod = Generator.module(driver: driver, control_system: control_system).save!
+      control_system = mod.control_system!
+      control_system.modules.should contain(mod.id)
+      control_system.modules.size.should eq 3
+
+      control_system2 = Generator.control_system
+      control_system2.modules = [device_mod2.id.as(String)]
+      control_system2.save!
+
+      control_system = ControlSystem.find!(control_system.id.as(String))
+      control_system.destroy
+
+      Module.find?(mod.id.as(String)).should be_nil
+      Module.find?(device_mod.id.as(String)).should be_nil
+      Module.find!(device_mod2.id.as(String)).id.should eq device_mod2.id
+      device_driver.destroy
+      driver.destroy
+    end
+
     describe "generation of json data" do
       it "#module_data" do
         cs = Generator.control_system.save!

src/placeos-models/control_system.cr

@@ -190,26 +190,25 @@ module PlaceOS::Model
     def cleanup_modules
       return if self.modules.empty?
 
-      # Locate modules that have no other associated ControlSystems
-      args = [] of String
-      query = ""
-
-      self.modules.each_with_index do |v, i|
-        args << v
-        query += ", " unless i == 0
-        query += "$#{i + 1}"
-      end
-
-      lonesome_modules = Module.find_all_by_sql(<<-SQL, args: args)
-        select m.* from "#{Module.table_name}" m, "#{ControlSystem.table_name}" s where m.id in (#{query}) and m.id = ANY(s.modules)
-      SQL
-
-      # Asynchronously remove the modules
-      lonesome_modules.map do |m|
+      modules_with_single_occurrence.map do |m|
         future { m.destroy }
       end.each(&.get)
     end
 
+    def modules_with_single_occurrence : Array(Module)
+      Module.where(%[
+        id IN (
+        SELECT module
+        FROM (
+            SELECT UNNEST(modules) AS module
+            FROM sys
+        ) AS module_list
+        WHERE module IN ('#{self.modules.join("', '")}')
+        GROUP BY module
+        HAVING COUNT(*) = 1)
+      ]).to_a
+    end
+
     # ensure all the modules are valid and exist
     def check_modules
       # TODO:: escape the modules list