1 files changed, 49 insertions, 0 deletions
diff --git a/lib/gitlab/sherlock/collection.rb b/lib/gitlab/sherlock/collection.rb
new file mode 100644
index 00000000000..66bd6258521
--- /dev/null
+++ b/lib/gitlab/sherlock/collection.rb
@@ -0,0 +1,49 @@
+module Gitlab
+  module Sherlock
+    # A collection of transactions recorded by Sherlock.
+    #
+    # Method calls for this class are synchronized using a mutex to allow
+    # sharing of a single Collection instance between threads (e.g. when using
+    # Puma as a webserver).
+    class Collection
+      include Enumerable
+
+      def initialize
+        @transactions = []
+        @mutex = Mutex.new
+      end
+
+      def add(transaction)
+        synchronize { @transactions << transaction }
+      end
+
+      alias_method :<<, :add
+
+      def each(&block)
+        synchronize { @transactions.each(&block) }
+      end
+
+      def clear
+        synchronize { @transactions.clear }
+      end
+
+      def empty?
+        synchronize { @transactions.empty? }
+      end
+
+      def find_transaction(id)
+        find { |trans| trans.id == id }
+      end
+
+      def newest_first
+        sort { |a, b| b.finished_at <=> a.finished_at }
+      end
+
+      private
+
+      def synchronize(&block)
+        @mutex.synchronize(&block)
+      end
+    end
+  end
+end