add update_constraints.sh for use by new release job

This script is based on the existing steps in release.sh for updating
the constraints list after releasing one of our Python projects. It's
placed in its own commit so it is available on the release nodes when
the new job in the following commit is merged.

Change-Id: Ie3e6d0e3501fa0cba251e000430bd0740a2bd331
Signed-off-by: Doug Hellmann <doug@doughellmann.com>

jenkins/scripts/release-tools/update_constraints.sh

@@ -0,0 +1,120 @@
+#!/bin/bash
+#
+# Script to update the constraints file in the requirements repo when
+# a release is tagged.
+#
+# All Rights Reserved.
+#
+#    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.
+
+set -x
+
+TOOLSDIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+source $TOOLSDIR/functions
+
+function usage {
+    echo "Usage: update_constraints.sh version"
+    echo
+    echo "Example: update_constraints.sh 3.0.3"
+}
+
+if [ $# -lt 1 ]; then
+    usage
+    exit 2
+fi
+
+VERSION=$1
+
+# Extract the tag message by parsing the git show output, which looks
+# something like:
+#
+# tag 2.0.0
+# Tagger: Doug Hellmann <doug@doughellmann.com>
+# Date:   Tue Dec 1 21:45:44 2015 +0000
+#
+# python-keystoneclient 2.0.0 release
+#
+# meta:version: 2.0.0
+# meta:series: mitaka
+# meta:release-type: release
+# -----BEGIN PGP SIGNATURE-----
+# Comment: GPGTools - http://gpgtools.org
+#
+# iQEcBAABAgAGBQJWXhUIAAoJEDttBqDEKEN62rMH/ihLAGfw5GxPLmdEpt7gsLJu
+# ...
+#
+TAG_META=$(git show --no-patch "$VERSION" | grep '^meta:' || true)
+if [[ -z "$TAG_META" ]]; then
+    echo "WARNING: Missing meta lines in $VERSION tag message,"
+    echo "         skipping announcement."
+    echo
+    echo "Was the tag for $VERSION created with release.sh?"
+    exit 0
+fi
+
+function get_tag_meta {
+    typeset fieldname="$1"
+
+    echo "$TAG_META" | grep "^meta:$fieldname:" | cut -f2 -d' '
+}
+
+# Find the series information from the tag metadata in the comment.
+SERIES=$(get_tag_meta series)
+
+# Pick up the repository name from the git URL.
+SHORTNAME=$(basename $(git config --local remote.origin.url))
+
+# Apply the PEP 503 rules to turn the dist name into a canonical form,
+# in case that's the version that appears in upper-constraints.txt. We
+# have to try substituting both versions because we have a mix in that
+# file and if we rename projects we'll end up with bad references to
+# existing build artifacts.
+function pep503 {
+    echo $1 | sed -e 's/[-_.]\+/-/g' | tr '[:upper:]' '[:lower:]'
+}
+
+# Try to propose a constraints update.
+#
+# NOTE(dhellmann): If the setup_requires dependencies are not
+# installed yet, running setuptools commands will install
+# them. Capturing the output of a setuptools command that includes
+# the output from installing packages produces a bad dist_name, so
+# we first ask for the name without saving the output and then we
+# ask for it again and save the output to get a clean
+# version. This is why we can't have nice things.
+python setup.py --name
+dist_name=$(python setup.py --name)
+canonical_name=$(pep503 $dist_name)
+if [[ -z "$dist_name" ]]; then
+    echo "Could not determine the name of the constraint to update"
+else
+    setup_temp_space update-constraints-$SHORTNAME
+    # NOTE(dhellmann): zuul-cloner defaults to checking out master if
+    # the named branch doesn't exist.
+    clone_repo openstack/requirements stable/$SERIES
+    cd openstack/requirements
+    git checkout -b "$dist_name-$VERSION"
+    sed -e "s/^${dist_name}=.*/$dist_name===$VERSION/" --in-place upper-constraints.txt
+    sed -e "s/^${canonical_name}=.*/$canonical_name===$VERSION/" --in-place upper-constraints.txt
+    if git commit -a -m "update constraint for $dist_name to new release $VERSION
+
+$TAG_META
+"; then
+        git show
+        git review -t 'new-release'
+    else
+        echo "Skipping git review because there are no updates."
+    fi
+fi
+
+exit 0