aws env variable string from 'aws sts assume-role' cli

get_aws_env_from_sts_assume_role.sh

#!/bin/bash
set -e

# Using jq command, you can format json to key=value string
session=$(aws sts assume-role --role-arn $ARN --role-session-name $USER --query 'Credentials')
env_options=$(echo $session | jq -r 'del(.Expiration) | to_entries | map([" ", "AWS_" + (.key | gsub("(?<l>[a-z])(?<f>[A-Z])";.l+"_"+.f)|ascii_upcase), "=", .value] | add) | add')
echo $env_options
#=> AWS_SECRET_ACCESS_KEY=xxxx AWS_SESSION_TOKEN=yyyy AWS_ACCESS_KEY_ID=zzzz

# Execute another aws cli using above credentials
env $env_options aws s3api list-buckets

# For docker usage, add "-e" argument
env_options=$(echo $session | jq -r 'del(.Expiration) | to_entries | map([" -e ", "AWS_" + (.key | gsub("(?<l>[a-z])(?<f>[A-Z])";.l+"_"+.f)|ascii_upcase), "=", .value] | add) | add')
#=> -e AWS_SECRET_ACCESS_KEY=xxxx -e AWS_SESSION_TOKEN=yyyy -e AWS_ACCESS_KEY_ID=zzzz
docker run --rm -it ${env_options} $IMAGE bash