hooks: Implement calling the reference-transaction hook

To enable the transition from voting on reference transaction via the
pre-receive hook towards the reference-transaction hook, we'll have to
start calling the latter from our Ruby sidecar. This commit thus
implements the logic to invoke the reference transaction hook, but
doesn't yet wire up this new hook implementation.

1 files changed, 11 insertions, 0 deletions

diff --git a/ruby/lib/gitlab/git/hook.rb b/ruby/lib/gitlab/git/hook.rb
index dd3875d2f..8a514da2c 100644
--- a/ruby/lib/gitlab/git/hook.rb
+++ b/ruby/lib/gitlab/git/hook.rb
@@ -35,6 +35,8 @@ module Gitlab
           case name
           when "pre-receive", "post-receive"
             call_receive_hook(gl_id, gl_username, oldrev, newrev, ref, push_options, transaction)
+          when "reference-transaction"
+            call_reference_transaction_hook(gl_id, gl_username, oldrev, newrev, ref, transaction)
           when "update"
             call_update_hook(gl_id, gl_username, oldrev, newrev, ref)
           end
@@ -85,6 +87,15 @@ module Gitlab
         call_stdin_hook([], changes, vars)
       end
 
+      def call_reference_transaction_hook(gl_id, gl_username, oldrev, newrev, ref, transaction)
+        changes = [oldrev, newrev, ref].join(" ")
+
+        vars = env_base_vars(gl_id, gl_username)
+        vars.merge!(transaction.env_vars) if transaction
+
+        call_stdin_hook(["prepared"], changes, vars)
+      end
+
       def call_update_hook(gl_id, gl_username, oldrev, newrev, ref)
         options = {
           chdir: repo_path