A simple script to approximate Azure spendings. This is far from accurate. Please comment if you know a better way

Monitor Azure Costs.sh

#! /usr/bin/env bash 
set -e

DAILY_SPENDING_LIMIT=3 # USD, per account

DATE_COMMAND="date"
if hash gdate 2>/dev/null
then
   DATE_COMMAND="gdate"
fi

subscriptions="$(az login -u "${AZURE_USERNAME}" -p "${AZURE_PASSWORD}" | jq -r '.[] | .id')"

get_costs () {
    subscription="$1"
    start_date="$2"
    end_date="$3"

    az account set --subscription "$subscription"

    # the sed piece converts scientific notation to a format that can be processed by `bc`
    # see https://stackoverflow.com/a/12882612/231644
    tmp_file="$(mktemp)"
    az consumption usage list --start-date "$start_date" --end-date "$end_date" | jq -r '.[] | .pretaxCost' \
    | sed -E 's/([+-]?[0-9.]+)[eE]\+?(-?)([0-9]+)/(\1*10^\2\3)/g' >> "$tmp_file"
    cost=$(paste -sd+ "$tmp_file" | bc | head -1 | sed 's/\\$//')
    rm -f "$tmp_file"
    
    printf "%.2f\n" "$cost"
}
   

for s in $subscriptions
do
    cost=$(get_costs "$s" "$($DATE_COMMAND --date='1 day ago' +%Y-%m-%d)" "$($DATE_COMMAND --date='today' +%Y-%m-%d)")
    if (( $(echo "$cost > "$DAILY_SPENDING_LIMIT"" | bc -l) )); then
        message="<!channel> :warning: Azure account ${s}\\n *Current cost \$$cost*. Cost since yesterday exceeds threshold \$${DAILY_SPENDING_LIMIT}."
	else
		message="ALL OK Azure account ${s}\\n *Current cost \$$cost* threshold \$${DAILY_SPENDING_LIMIT}."
	fi
	# Send to slack
        ...
	done