1 files changed, 62 insertions, 0 deletions
diff --git a/lib/gitlab/gpg.rb b/lib/gitlab/gpg.rb
new file mode 100644
index 00000000000..e1d1724295a
--- /dev/null
+++ b/lib/gitlab/gpg.rb
@@ -0,0 +1,62 @@
+module Gitlab
+  module Gpg
+    extend self
+
+    module CurrentKeyChain
+      extend self
+
+      def add(key)
+        GPGME::Key.import(key)
+      end
+
+      def fingerprints_from_key(key)
+        import = GPGME::Key.import(key)
+
+        return [] if import.imported == 0
+
+        import.imports.map(&:fingerprint)
+      end
+    end
+
+    def fingerprints_from_key(key)
+      using_tmp_keychain do
+        CurrentKeyChain.fingerprints_from_key(key)
+      end
+    end
+
+    def primary_keyids_from_key(key)
+      using_tmp_keychain do
+        fingerprints = CurrentKeyChain.fingerprints_from_key(key)
+
+        GPGME::Key.find(:public, fingerprints).map { |raw_key| raw_key.primary_subkey.keyid }
+      end
+    end
+
+    def user_infos_from_key(key)
+      using_tmp_keychain do
+        fingerprints = CurrentKeyChain.fingerprints_from_key(key)
+
+        GPGME::Key.find(:public, fingerprints).flat_map do |raw_key|
+          raw_key.uids.map { |uid| { name: uid.name, email: uid.email } }
+        end
+      end
+    end
+
+    def using_tmp_keychain
+      Dir.mktmpdir do |dir|
+        @original_dirs ||= [GPGME::Engine.dirinfo('homedir')]
+        @original_dirs.push(dir)
+
+        GPGME::Engine.home_dir = dir
+
+        return_value = yield
+
+        @original_dirs.pop
+
+        GPGME::Engine.home_dir = @original_dirs[-1]
+
+        return_value
+      end
+    end
+  end
+end