Add script which helps abandon old patches in gerrit

This script is almost the same as script in neutron repo [1]
but without closing Launchpad bugs as Tobiko don't use Launchpad
as a bug tracker.

[1] https://opendev.org/openstack/neutron/src/branch/master/tools/abandon_old_reviews.sh

Change-Id: I790c6692b05382353e630d23e3b45245a09b678f

tools/abandon_old_reviews.sh

@@ -0,0 +1,112 @@
+#!/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.
+#
+# WARNING!
+# Please do not run this script without talking to the Tobiko Core team. Auto
+# abandoning people's changes is a good thing, but must be done with care.
+#
+# before you run this modify your .ssh/config to create a
+# review.opendev.org entry:
+#
+#   Host review.opendev.org
+#   User <yourgerritusername>
+#   Port 29418
+#
+
+# Note: due to gerrit bug somewhere, this double posts messages. :(
+
+# first purge all the reviews that are more than 4w old and blocked by a core -2
+
+DRY_RUN=0
+PROJECTS="(x/tobiko OR x/devstack-plugin-tobiko)"
+
+function print_help {
+    echo "Script to abandon patches without activity for more than 4 weeks."
+    echo "Usage:"
+    echo "      ./abandon_old_reviews.sh [--dry-run] [--help]"
+    echo " --dry-run                    In dry-run mode it will only print what patches would be abandoned "
+    echo "                              but will not take any real actions in gerrit"
+    echo " --help                       Print help message"
+}
+
+while [ $# -gt 0 ]; do
+    key="${1}"
+
+    case $key in
+        --dry-run)
+            echo "Enabling dry run mode"
+            DRY_RUN=1
+            shift # past argument
+        ;;
+        --help)
+            print_help
+            exit 2
+    esac
+done
+
+set -o errexit
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
+function abandon_review {
+    local gitid=$1
+    shift
+    local msg=$@
+    # echo ssh review.opendev.org gerrit review $gitid --abandon --message \"$msg\"
+    if [ $DRY_RUN -eq 1 ]; then
+        echo "Would abandon $gitid"
+    else
+        echo "Abandoning $gitid"
+        ssh review.opendev.org gerrit review $gitid --abandon --message \"$msg\"
+    fi
+}
+
+blocked_reviews=$(ssh review.opendev.org "gerrit query --current-patch-set --format json $PROJECTS status:open age:4w label:Code-Review<=-2" | jq .currentPatchSet.revision | grep -v null | sed 's/"//g')
+
+blocked_msg=$(cat <<EOF
+
+This review is > 4 weeks without comment and currently blocked by a
+core reviewer with a -2. We are abandoning this for now.
+
+Feel free to reactivate the review by pressing the restore button and
+contacting the reviewer with the -2 on this review to ensure you
+address their concerns.
+
+EOF
+)
+
+for review in $blocked_reviews; do
+    # echo ssh review.opendev.org gerrit review $review --abandon --message \"$msg\"
+    echo "Blocked review $review"
+    abandon_review $review $blocked_msg
+done
+
+# then purge all the reviews that are > 4w with no changes and Jenkins has -1ed
+
+failing_reviews=$(ssh review.opendev.org "gerrit query  --current-patch-set --format json $PROJECTS status:open age:4w NOT label:Verified>=1,Zuul" | jq .currentPatchSet.revision | grep -v null | sed 's/"//g')
+
+failing_msg=$(cat <<EOF
+
+This review is > 4 weeks without comment, and failed Jenkins the last
+time it was checked. We are abandoning this for now.
+
+Feel free to reactivate the review by pressing the restore button and
+leaving a 'recheck' comment to get fresh test results.
+
+EOF
+)
+
+for review in $failing_reviews; do
+    echo "Failing review $review"
+    abandon_review $review $failing_msg
+done