Add script to compute diff in Jenkins job config changes

hack/jenkins/diff-job-config-patch.sh

@@ -0,0 +1,72 @@
+#!/bin/bash
+
+# Copyright 2016 The Kubernetes Authors 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.
+
+# Uses the kubekins-job-builder Docker image to compute the differences in
+# the Jenkins job config XML, comparing the current git branch against upstream
+# master. The filename containing the diff is printed at the end, assuming
+# everything parsed successfully.
+
+# Note: anecdotal evidence suggests this doesn't work correctly on OS X.
+# If you find that there is no diff being generated, you may want to try setting
+# OUTPUT_DIR to some directory in your home directory.
+
+# When running this script from inside Docker, you must set REPO_ROOT to point
+# to the path to the repository on the host, and DOCKER_VOLUME_OUTPUT_DIR must
+# point to the path of $OUTPUT_DIR on the host. This is due to the way volume
+# mounts work in Docker-in-Docker.
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+readonly JOB_CONFIGS_ROOT="hack/jenkins/job-configs"
+readonly JOB_BUILDER_IMAGE='gcr.io/google_containers/kubekins-job-builder:1'
+
+KUBE_ROOT=$(cd $(dirname "${BASH_SOURCE}")/../.. && pwd)
+REPO_DIR=${REPO_DIR:-"${KUBE_ROOT}"}
+
+readonly output_dir=${OUTPUT_DIR:=$(mktemp -d -t JJB-XXXXX)}
+readonly docker_volume_output_dir=${DOCKER_VOLUME_OUTPUT_DIR:="${output_dir}"}
+readonly diff_file="${output_dir}/diff.txt"
+
+mkdir -p "${output_dir}/upstream" "${output_dir}/patch"
+
+echo "Saving output in ${output_dir}"
+
+readonly common_commands="\
+  git describe --long --tags --abbrev=14 >/output/gitversion.txt && \
+  git rev-parse --abbrev-ref HEAD >/output/gitbranch.txt && \
+  jenkins-jobs test \
+    '${JOB_CONFIGS_ROOT}:${JOB_CONFIGS_ROOT}/kubernetes-jenkins' \
+    -o /output/kubernetes-jenkins && \
+  jenkins-jobs test \
+    '${JOB_CONFIGS_ROOT}:${JOB_CONFIGS_ROOT}/kubernetes-jenkins-pull' \
+    -o /output/kubernetes-jenkins-pull"
+
+docker run --rm=true -i \
+  -v "${docker_volume_output_dir}/upstream:/output" \
+  "${JOB_BUILDER_IMAGE}" \
+  bash -c "git checkout master && git pull && ${common_commands}"
+
+docker run --rm=true -i \
+  -v "${docker_volume_output_dir}/patch:/output" \
+  -v "${REPO_DIR}:/kubernetes:ro" \
+  "${JOB_BUILDER_IMAGE}" \
+  bash -c "${common_commands}"
+
+diff -ruN "${output_dir}/upstream" "${output_dir}/patch" >"${diff_file}" || true
+echo
+echo "  *** Diff saved in ${diff_file} ***"