From a09f0255f71d2c06d748922aa2e5e6390a0d75a0 Mon Sep 17 00:00:00 2001
From: Jeremy Stanley <fungi@yuggoth.org>
Date: Fri, 10 Apr 2015 14:38:13 +0000
Subject: [PATCH] Change proposals fall back on proposed branches

During the RC period for a project, there may already be a stable
branch for the release on the triggering project and a proposed
branch on the target project. If so, we want stable changes proposed
to the proposed branch. That's not confusing!

Change-Id: I488bb9ff63daf9d012e41dbaa178b1656eaeffad
---
 jenkins/scripts/propose_update.sh | 70 ++++++++++++++++++-------------
 1 file changed, 40 insertions(+), 30 deletions(-)

diff --git a/jenkins/scripts/propose_update.sh b/jenkins/scripts/propose_update.sh
index c8ff6a7faf..22005e7a87 100755
--- a/jenkins/scripts/propose_update.sh
+++ b/jenkins/scripts/propose_update.sh
@@ -25,11 +25,10 @@ else
     TOPIC="openstack/openstack-manuals"
 fi
 USERNAME="proposal-bot"
-BRANCH=$ZUUL_REF
 ALL_SUCCESS=0
 
-if [ -z "$BRANCH" ] ; then
-    echo "No branch set, exiting."
+if [ -z "$ZUUL_REF" ] ; then
+    echo "No ZUUL_REF set, exiting."
     exit 1
 fi
 
@@ -39,38 +38,49 @@ git config gitreview.username "proposal-bot"
 
 for PROJECT in $(cat projects.txt); do
 
-    change_id=""
-    # See if there is an open change in the openstack/requirements topic
-    # If so, get the change id for the existing change for use in the
-    # commit msg.
-    change_info=$(ssh -p 29418 $USERNAME@review.openstack.org gerrit query --current-patch-set status:open project:$PROJECT topic:$TOPIC owner:$USERNAME branch:$BRANCH)
-    previous=$(echo "$change_info" | grep "^  number:" | awk '{print $2}')
-    if [ "x${previous}" != "x" ] ; then
-        change_id=$(echo "$change_info" | grep "^change" | awk '{print $2}')
-        # read return a non zero value when it reaches EOF. Because we use a
-        # heredoc here it will always reach EOF and return a nonzero value.
-        # Disable -e temporarily to get around the read.
-        # The reason we use read is to allow for multiline variable content
-        # and variable interpolation. Simply double quoting a string across
-        # multiple lines removes the newlines.
-        set +e
-        read -d '' COMMIT_MSG <<EOF
-$INITIAL_COMMIT_MSG
-
-Change-Id: $change_id
-EOF
-        set -e
-    else
-        COMMIT_MSG=$INITIAL_COMMIT_MSG
-    fi
-
     PROJECT_DIR=$(basename $PROJECT)
     rm -rf $PROJECT_DIR
     git clone ssh://$USERNAME@review.openstack.org:29418/$PROJECT.git
     pushd $PROJECT_DIR
 
-    # make sure the project even has this branch
-    if git branch -a | grep -q "^  remotes/origin/$BRANCH$" ; then
+    # check whether the project has this branch or a suitable fallback
+    BRANCH=""
+    if git branch -a | grep -q "^  remotes/origin/$ZUUL_REF$" ; then
+        BRANCH=$ZUUL_REF
+    elif echo $ZUUL_REF | grep -q "^stable/" ; then
+        FALLBACK=`echo $ZUUL_REF | sed s,^stable/,proposed/,`
+        if git branch -a | grep -q "^  remotes/origin/$FALLBACK$" ; then
+            BRANCH=$FALLBACK
+        fi
+    fi
+
+    # don't bother with this project if there's not a usable branch
+    if [ -n "$BRANCH" ] ; then
+        change_id=""
+        # See if there is an open change in the openstack/requirements topic
+        # If so, get the change id for the existing change for use in the
+        # commit msg.
+        change_info=$(ssh -p 29418 $USERNAME@review.openstack.org gerrit query --current-patch-set status:open project:$PROJECT topic:$TOPIC owner:$USERNAME branch:$BRANCH)
+        previous=$(echo "$change_info" | grep "^  number:" | awk '{print $2}')
+        if [ "x${previous}" != "x" ] ; then
+            change_id=$(echo "$change_info" | grep "^change" | awk '{print $2}')
+            # read return a non zero value when it reaches EOF. Because we use a
+            # heredoc here it will always reach EOF and return a nonzero value.
+            # Disable -e temporarily to get around the read.
+            # The reason we use read is to allow for multiline variable content
+            # and variable interpolation. Simply double quoting a string across
+            # multiple lines removes the newlines.
+            set +e
+            read -d '' COMMIT_MSG <<EOF
+$INITIAL_COMMIT_MSG
+
+Change-Id: $change_id
+EOF
+            set -e
+        else
+            COMMIT_MSG=$INITIAL_COMMIT_MSG
+        fi
+
         git checkout -B ${BRANCH} -t origin/${BRANCH}
         # Need to set the git config in each repo as we shouldn't
         # set it globally for the Jenkins user on the slaves.