terraform init wrapper - backend switch and environment name export.

tfinist.sh

#!/usr/bin/env bash
#
# This script is used for configuring terraform and it's remote state backend
# for a specific environment. This is done by sourcing a backend config in the
# `dev` folder under the git root directory. Note that the backend config file
# name needs to end with a `.hcl` extension and the file basename is used as
# the environment name provided. It also sets a `TF_VAR_envname` with the
# environment name as value.
#
# For distinguishing the different environments the script also sets `PS1`.
#
# To unset the current environment the user can call the exported
# `deactivate` function.
#
# Usage: `source tfinit.sh <envname>`

deactivate() {
    PS1="$_OLD_PS1"
    export PS1
    unset _OLD_PS1
    unset TF_VAR_envname
    unset TF_DATA_DIR
    unset -f deactivate
}

usage="Usage: source ${BASH_SOURCE:-$0} <envname> [--empty]"
if [[ "${BASH_SOURCE-}" = "$0" ]]; then
    echo "$usage" >&2
    exit 1
fi

if (( $# > 2 )); then
    echo "${usage}" >&2
    return 1
fi

envname="$1"
export TF_VAR_envname="${envname}"
export TF_DATA_DIR=".terraform-${envname}"

if [[ "$2" = "--empty" ]]; then
    terraform init
else
    backendconfig="$(git rev-parse --show-toplevel)/env/${envname}.hcl"
    terraform init -reconfigure -backend-config "${backendconfig}"
fi

if [[ "$?" -ne 0 ]]; then
    return "$?"
fi

export _OLD_PS1="${_OLD_PS1:=$PS1}"
export PS1="(${envname})${_OLD_PS1}"