lib/percheron/actions/start.rb in percheron-0.8.0 vs lib/percheron/actions/start.rb in percheron-0.8.1

@@ -1,43 +1,63 @@
 module Percheron
   module Actions
     class Start
       include Base
 
-      def initialize(unit, needed_units: [], cmd: false, exec_scripts: true)
+      def initialize(unit, needed_units: [], create: true, cmd: false, exec_scripts: true)
         @unit = unit
         @needed_units = needed_units
+        @create = create
         @cmd = cmd
         @exec_scripts = exec_scripts
       end
 
       def execute!
-        results = []
-        results << create!
-        unless unit.running?
+        return nil if unit.running?
+        results = [ create! ]
+        if unit.startable?
           results << start!
           results << execute_post_start_scripts!
         end
         results.compact.empty? ? nil : unit
       end
 
       private
 
-        attr_reader :unit, :needed_units, :cmd, :exec_scripts
+        attr_reader :unit, :needed_units, :create, :cmd, :exec_scripts
+        alias_method :create?, :create
 
         def exec_scripts?
           !unit.post_start_scripts.empty? && exec_scripts
         end
 
         def create!
-          return nil if unit.exists?
+          return nil unless create?
           Create.new(unit, cmd: cmd).execute!
         end
 
         def start!
-          return nil if !unit.startable? || unit.running?
-          $logger.info "Starting '#{unit.display_name}' unit"
-          unit.container.start!
+          return nil if unit_running?
+          if needed_unit_names_not_running.empty?
+            $logger.info "Starting '#{unit.display_name}' unit"
+            unit.container.start!
+          else
+            $logger.error "Cannot start '%s' unit, %s not running" %
+              [ unit.display_name, needed_unit_names_not_running ]
+          end
+        end
+
+        def unit_running?
+          !unit.startable? || unit.running?
+        end
+
+        def needed_unit_names_not_running
+          @needed_unit_names_not_running ||= begin
+            unit.startable_needed_units.each_with_object([]) do |unit_tuple, all|
+              _, unit = unit_tuple
+              all << unit.name unless unit.running?
+            end
+          end
         end
 
         def execute_post_start_scripts!
           scripts = unit.post_start_scripts
           Exec.new(unit, needed_units, scripts, 'POST start').execute! if exec_scripts?