Simple script that will use your MFA token to set AWS credentials

get-session-token.sh

#!/bin/bash -e

# $1 = token from your authenticator
#
# usage:
# ./get-session-token.sh 123456
#

# the profile name with your credentials
PROFILE=""

# your MFA ARN from AWS
MFA_ARN=""

# token expiration (seconds)
DURATION_SEC="129600"

# file to append session token creds
CRED_FILE=~/.aws/credentials

# set colors for output
NO_COLOR='\033[0m'
PRE_COLOR='\033[1;35m'

JSON=$(aws --profile $PROFILE sts get-session-token --duration-seconds $DURATION_SEC --serial-number $MFA_ARN --token-code $1)

AKID=$(echo $JSON | jq -r .Credentials.AccessKeyId)
ST=$(echo $JSON | jq -r .Credentials.SessionToken)
SAK=$(echo $JSON | jq -r .Credentials.SecretAccessKey)

cat >> $CRED_FILE <<EOF

## auto added `date`
[default]
aws_access_key_id = $AKID
aws_secret_access_key = $SAK
aws_session_token = $ST
EOF

if [ -n "$EDITOR" ]; then
  $EDITOR $CRED_FILE
else
  printf "Open $PRE_COLOR$CRED_FILE$NO_COLOR to see what was added\n"
fi