Merge pull request #62495 from rmmh/bzl-cache

Automatic merge from submit-queue (batch tested with PRs 62495, 63003, 62829, 62151, 62002). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Add a GCS mirror to WORKSPACE URLs, along with a script to update them.

**What this PR does / why we need it**:
We get occasional flakes when WORKSPACE downloads fail. This should make that much more unlikely, by having two independent endpoints to try.

**Release note**:
```release-note
NONE
```

hack/BUILD

@@ -72,3 +72,10 @@ go_library(
     srcs = ["e2e.go"],
     importpath = "k8s.io/kubernetes/hack",
 )
+
+sh_binary(
+    name = "update-mirror",
+    srcs = ["update-workspace-mirror.sh"],
+    args = ["$(location @workspace_urls//:urls.txt)"],
+    data = ["@workspace_urls//:urls.txt"],
+)

hack/update-workspace-mirror.sh

@@ -0,0 +1,43 @@
+#!/bin/bash
+
+# Copyright 2018 The Kubernetes Authors.
+#
+# 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 -o errexit
+set -o nounset
+set -o pipefail
+
+if [[ $# -ne 1 ]]; then
+    echo 'use "bazel run //build:update-mirror"'
+    echo "(usage: $0 <file with list of URLs to mirror>)"
+    exit 1
+fi
+
+BUCKET="gs://k8s-bazel-cache"
+
+gsutil acl get "${BUCKET}" > /dev/null
+
+tmpfile=$(mktemp bazel_workspace_mirror.XXXXXX)
+trap "rm ${tmpfile}" EXIT
+cat "$1" | while read url; do
+  echo "${url}"
+  if gsutil ls "${BUCKET}/${url}" &> /dev/null; then
+    echo present
+  else
+    echo missing
+    if curl -fLag "${url}" > "${tmpfile}"; then
+        gsutil cp -a public-read "${tmpfile}" "${BUCKET}/${url}"
+    fi
+  fi
+done