diskimage-builder/elements/cache-url/bin/cache-url
Victor Lowther 43b70ce224 /bin/bash all the things.
Since we are using bash syntax in some of the element fragments,
we should make sure we use bash for all of them, so that things don't
break on systems where /bin/sh != /bin/bash.

Change-Id: If2f043c57aa4e1492b7f9839213ef6123f683612
2013-11-17 16:59:31 -06:00

63 lines
2.0 KiB
Bash
Executable File

#!/bin/bash
# Copyright 2012 Hewlett-Packard Development Company, L.P.
# All Rights Reserved.
# Copyright 2013 Red Hat, Inc.
#
# 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 -e
# Download a URL to a local cache
# e.g. cache-url http://.../foo ~/.cache/image-create/foo
url=$1
dest=$2
mkdir -p $(dirname $dest)
tmp=$(mktemp $(dirname $dest)/.download.XXXXXXXX)
if [ -f $dest -a -s $dest ] ; then
time_cond="-z $dest"
success="Server copy has changed. Using server version of $url"
else
success="Downloaded and cached $url for the first time"
fi
rcode=$(curl -L -o $tmp -w '%{http_code}' $url $time_cond)
if [ "$rcode" = "200" ] ; then
# In cases where servers ignore the Modified time,
# curl cancels the download, outputs a 200 and leaves
# the output file untouched, we don't want this empty file.
if [ -n "$time_cond" -a ! -s $tmp ] ; then
echo "Ignoring empty file returned by curl. Using locally cached $url"
rm -f $tmp
else
echo $success
mv $tmp $dest
fi
# 213 is the response to a ftp MDTM command, curl outputs a 213 as the status
# if the url redirected to a ftp server and Not-Modified
elif [ "$rcode" = "304" -o "$rcode" = "213" ] ; then
echo "Server copy has not changed. Using locally cached $url"
rm -f $tmp
else
echo "Server returned an unexpected response code. [$rcode]"
rm -f $tmp
# expose some error codes so the calling process might know what happened
if [ "$rcode" = "404" ] ; then
exit 44
fi
exit 1
fi