1 files changed, 54 insertions, 0 deletions
diff --git a/app/services/merge_requests/mergeability/run_checks_service.rb b/app/services/merge_requests/mergeability/run_checks_service.rb
new file mode 100644
index 00000000000..c1d65fb65cc
--- /dev/null
+++ b/app/services/merge_requests/mergeability/run_checks_service.rb
@@ -0,0 +1,54 @@
+# frozen_string_literal: true
+module MergeRequests
+  module Mergeability
+    class RunChecksService
+      include Gitlab::Utils::StrongMemoize
+
+      # We want to have the cheapest checks first in the list,
+      # that way we can fail fast before running the more expensive ones
+      CHECKS = [
+        CheckCiStatusService
+      ].freeze
+
+      def initialize(merge_request:, params:)
+        @merge_request = merge_request
+        @params = params
+      end
+
+      def execute
+        CHECKS.each_with_object([]) do |check_class, results|
+          check = check_class.new(merge_request: merge_request, params: params)
+
+          next if check.skip?
+
+          check_result = run_check(check)
+          results << check_result
+
+          break results if check_result.failed?
+        end
+      end
+
+      private
+
+      attr_reader :merge_request, :params
+
+      def run_check(check)
+        return check.execute unless Feature.enabled?(:mergeability_caching, merge_request.project, default_enabled: :yaml)
+        return check.execute unless check.cacheable?
+
+        cached_result = results.read(merge_check: check)
+        return cached_result if cached_result.respond_to?(:status)
+
+        check.execute.tap do |result|
+          results.write(merge_check: check, result_hash: result.to_hash)
+        end
+      end
+
+      def results
+        strong_memoize(:results) do
+          Gitlab::MergeRequests::Mergeability::ResultsStore.new(merge_request: merge_request)
+        end
+      end
+    end
+  end
+end