get a vault token using azure

azure-token.sh

#!/bin/bash -e
api_version="2018-02-01"
resource="https://<your resource URL>"

instance_data=$(curl -s -H 'Metadata: true' "http://169.254.169.254/metadata/instance?api-version=${api_version}")
offer_data=$(curl -s -H 'Metadata: true' "http://169.254.169.254/metadata/identity/oauth2/token?api-version=${api_version}&resource=${resource}")

rg=$(jq -r .compute.resourceGroupName <<< $instance_data)
type=vmss
name=$(jq -er .compute.vmScaleSetName <<< $instance_data)
if [[ $? -ne 0 || -z $name ]]; then
  type=vm
  name=$(jq -r .compute.name <<< $instance_data)
fi
subscription_id=$(jq -r .compute.subscriptionId <<< $instance_data)

jwt=$(jq -r .access_token <<< $offer_data)

vault write auth/azure/login role="$1" subscription_id="${subscription_id}" resource_group_name="${rg}" ${type}_name="${name}" jwt="${jwt}"