Fix REFNAME in propose_update.sh

ZUUL_REFNAME is not set in periodic pipelines.

Provide optionally branch and use that one instead if REFNAME is not set
to mimic how the script was used in v2.

Change-Id: I3a514b5ffd9d0797c1bd43a0762bd5709630b1cd

jenkins/scripts/propose_update.sh

@@ -20,6 +20,7 @@ if [ -z "$OWN_PROJECT" ] ; then
     echo "usage: $0 project"
     exit 1
 fi
+
 if [ "$OWN_PROJECT" == "requirements" ] ; then
     INITIAL_COMMIT_MSG="Updated from global requirements"
     TOPIC="openstack/requirements"
@@ -87,9 +88,16 @@ fi
 USERNAME="proposal-bot"
 ALL_SUCCESS=0
 
+# In periodic pipelines, ZUUL_REFNAME is not set, use BRANCH_NAME
+# instead here. The JJB scripts in v2 set always ZUUL_REFNAME, in v3
+# we pass in the branch as additional parameter.
 if [ -z "$ZUUL_REFNAME" ] ; then
-    echo "No ZUUL_REFNAME set, exiting."
-    exit 1
+    BRANCH_NAME=$2
+    if [ -z "$BRANCH_NAME" ] ; then
+        echo "usage: $0 project branch"
+        exit 1
+    fi
+    ZUUL_REFNAME=$BRANCH_NAME
 fi
 
 setup_git

playbooks/proposal/propose-updates.yaml

@@ -2,7 +2,7 @@
   tasks:
 
     - name: Run propose_update.sh script
-      command: "{{ ansible_user_dir }}/scripts/propose_update.sh {{ update_target }}"
+      command: "{{ ansible_user_dir }}/scripts/propose_update.sh {{ update_target }} {{zuul.branch}}"
       args:
         chdir: "src/{{ zuul.project.canonical_name }}"
       environment: '{{ zuul | zuul_legacy_vars }}'