Add helper script to abandon open changes

To delete stable/<series> branches first we have to abandon all open
changes otherwise gerrit does not allow to delete the branch.
This script abandons all the open patches on a given project on a
specific branch.

Change-Id: I431fb305f998608889510f8ed2914583891d2167

doc/source/reference/using.rst

@@ -867,6 +867,19 @@ This script list these stable/branches and offers to delete them.
 
    Only release managers have the access rights to delete branches.
 
+tools/abandon_patches_on_branch.sh
+----------------------------------
+
+A script to help abandoning open patches when a given branch transitions
+to ``Unmaintained`` or ``End of Life`` and all patches on stable/<series>
+branch needs to be abandoned in order to be able to delete that branch.
+
+Example:
+
+::
+
+  tools/abandon_patches_on_branch.sh yoga $(list-deliverables --series yoga)
+
 tools/list_unbranched_projects.sh
 ---------------------------------
 

tools/abandon_patches_on_branch.sh

@@ -0,0 +1,82 @@
+#!/usr/bin/env bash
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+# This script helps to abandon open patches when a given branch transitions
+# to Unmaintained or End of Life and all patches on stable/<series> branch
+# needs to be abandoned in order to be able to delete that branch.
+
+set -e
+
+if [[ $# -lt 2 ]]; then
+    echo "Usage: $(basename $0) <branch> <repo> [<repo>...]"
+    echo "repo should be e.g. glance"
+    echo
+    echo "Example: $(basename $0) yoga \$(list-deliverables --series yoga --is-eom)"
+    echo "     or: $(basename $0) ussuri \$(list-deliverables --series ussuri --is-eol)"
+    echo "     or: $(basename $0) 2023.1 \$(list-deliverables --series antelope)"
+    echo
+    echo " !!! WARNING: please do not run this script without discussing it"
+    echo "              first with release managers!"
+    exit 1
+fi
+
+series="$1"
+shift
+repos="$@"
+
+function abandon_change {
+    gitid=$1
+    msg=$2
+    commit_message=$(ssh review.opendev.org "gerrit query $gitid --current-patch-set --format json" | head -n1 | jq .subject)
+    echo "Abandoning: $change -- $commit_message"
+    ssh review.opendev.org gerrit review $gitid --abandon --message \"$msg\"
+}
+
+
+
+if [[ -z "$TARGET" ]]; then
+    echo
+    read -p "> Is stable/$series transitioning to Unmaintained or End of Life? [u/e]: " TARGET
+fi
+
+if [ "${TARGET,,}" != "u" ] && [ "${TARGET,,}" != "e" ]; then
+    echo "Please choose either u or e."
+    exit 1
+fi
+
+for repo in $repos; do
+    echo "Processing repository: $repo..."
+    open_changes=$(
+        ssh review.opendev.org "gerrit query --current-patch-set --format json \
+        status:open branch:stable/${series} project:openstack/${repo}" | \
+        jq .currentPatchSet.revision | grep -v null | sed 's/"//g'
+    )
+
+    if [ "${TARGET,,}" == "u" ]; then
+        abandon_message="stable/$series branch of openstack/$repo is about to be deleted.
+To be able to do that, all open patches need to be abandoned.
+Please cherry pick the patch to unmaintained/$series if you want to
+further work on this patch."
+    else
+        abandon_message="
+stable/$series branch of openstack/$repo transitioned to End of Life
+and is about to be deleted.
+To be able to do that, all open patches need to be abandoned."
+    fi
+
+    for change in $open_changes; do
+        abandon_change $change "$abandon_message"
+    done
+done
+