Prometheus json/yaml URL to file_sd_config downloader.

url_sd_config.sh

#!/bin/bash
#
# Description: Download a URL and write out a file_sd_config.
# Author: Ben Kochie <superq@gmail.com>

set -o pipefail

if [[ $# -ne 2 || $1 == "-h" ]] ; then
  echo "usage $(basename $0) <url> <sd file>"
  exit
fi

url="$1"
sd_file="$2"

tmpfile="$(mktemp /tmp/url_sd_config.XXXXXXX)"

cleanup() {
  rm "${tmpfile}"
}
trap cleanup EXIT

# Use location to follow any redirects.
curl --silent --compressed --fail --location --output "${tmpfile}" "${url}"

if [[ $? -ne 0 ]] ; then
  echo "Failed to get ${url}"
  exit 1
fi

cat "${tmpfile}" | sponge "${sd_file}"