1 files changed, 101 insertions, 0 deletions
diff --git a/lib/system_check/simple_executor.rb b/lib/system_check/simple_executor.rb
new file mode 100644
index 00000000000..e5986612908
--- /dev/null
+++ b/lib/system_check/simple_executor.rb
@@ -0,0 +1,101 @@
+module SystemCheck
+  # Simple Executor is current default executor for GitLab
+  # It is a simple port from display logic in the old check.rake
+  #
+  # There is no concurrency level and the output is progressively
+  # printed into the STDOUT
+  #
+  # @attr_reader [Array<BaseCheck>] checks classes of corresponding checks to be executed in the same order
+  # @attr_reader [String] component name of the component relative to the checks being executed
+  class SimpleExecutor
+    attr_reader :checks
+    attr_reader :component
+
+    # @param [String] component name of the component relative to the checks being executed
+    def initialize(component)
+      raise ArgumentError unless component.is_a? String
+
+      @component = component
+      @checks = Set.new
+    end
+
+    # Add a check to be executed
+    #
+    # @param [BaseCheck] check class
+    def <<(check)
+      raise ArgumentError unless check < BaseCheck
+      @checks << check
+    end
+
+    # Executes defined checks in the specified order and outputs confirmation or error information
+    def execute
+      start_checking(component)
+
+      @checks.each do |check|
+        run_check(check)
+      end
+
+      finished_checking(component)
+    end
+
+    # Executes a single check
+    #
+    # @param [SystemCheck::BaseCheck] check_klass
+    def run_check(check_klass)
+      $stdout.print "#{check_klass.display_name} ... "
+
+      check = check_klass.new
+
+      # When implements skip method, we run it first, and if true, skip the check
+      if check.can_skip? && check.skip?
+        $stdout.puts check_klass.skip_reason.color(:magenta)
+        return
+      end
+
+      # When implements a multi check, we don't control the output
+      if check.is_multi_check?
+        check.multi_check
+        return
+      end
+
+      if check.check?
+        $stdout.puts check_klass.check_pass.color(:green)
+      else
+        $stdout.puts check_klass.check_fail.color(:red)
+
+        if check.can_repair?
+          $stdout.print 'Trying to fix error automatically. ...'
+          if check.repair!
+            $stdout.puts 'Success'.color(:green)
+            return
+          else
+            $stdout.puts 'Failed'.color(:red)
+          end
+        end
+
+        check.show_error
+      end
+    rescue StandardError => e
+      $stdout.puts "Exception: #{e.message}".color(:red)
+    end
+
+    private
+
+    # Prints header content for the series of checks to be executed for this component
+    #
+    # @param [String] component name of the component relative to the checks being executed
+    def start_checking(component)
+      $stdout.puts "Checking #{component.color(:yellow)} ..."
+      $stdout.puts ''
+    end
+
+    # Prints footer content for the series of checks executed for this component
+    #
+    # @param [String] component name of the component relative to the checks being executed
+    def finished_checking(component)
+      $stdout.puts ''
+      $stdout.puts "Checking #{component.color(:yellow)} ... #{'Finished'.color(:green)}"
+      $stdout.puts ''
+    end
+  end
+end