Install Amazon ECR Docker Credential Helper on GNU/Linux x86_64/amd64

install-docker-credential-ecr-login.sh

#!/usr/bin/env bash

# install-docker-credential-ecr-login.sh
#
#   Install and configure AWS CLI v2 and the Amazon ECR Docker Credential Helper


# Exit immediately on error
set -o errexit
# All variables should be explicitly declared
set -o nounset
# Exit on error in a loop
set -o pipefail
# Debug
#set -o xtrace


APT_UPDATED=
AWS_CLI_URL='https://awscli.amazonaws.com/awscli-exe-linux-x86_64.zip'
AWS_ECR_CRED_HLPR_URL='https://amazon-ecr-credential-helper-releases.s3.us-east-2.amazonaws.com/0.4.0/linux-amd64/docker-credential-ecr-login'
DOCKER_CONFIG="$HOME/.docker/config.json"
TMPDIR=

__check_command_exists() {
    command -v "$1" > /dev/null 2>&1
}

__exit_cleanup() {
    EXIT_CODE=$?
    # Cleanup temp dir if it was ever created
    if [[ -n $TMPDIR ]]; then
        rm --recursive  --interactive=never "$TMPDIR"
    fi
    exit $EXIT_CODE
}

__make_temp_dir() {
    TMPDIR=$(mktemp --directory)
    # Bail out if the temp directory wasn't created successfully
    if ! [[ -d $TMPDIR ]]; then
        >&2 echo "Failed to create temp directory"
        exit 1
    fi
}

__apt_install_missing() {
    if ! __check_command_exists "$1"; then
        if [[ -z $APT_UPDATED ]]; then
            $SUDO apt update
            APT_UPDATED=yes
        fi
        $SUDO sh -c "DEBIAN_FRONTEND=noninteractive \
            apt install -y -o DPkg::Options::=--force-confold $1"
    fi
}

install_dependencies() {
    __apt_install_missing unzip
    __apt_install_missing wget
}

install_awscli() {
    __check_command_exists aws && return 0
    install_dependencies
    __make_temp_dir
    AWS_CLI_ARCHIVE="${TMPDIR}/${AWS_CLI_URL##*/}"
    wget -q -O "$AWS_CLI_ARCHIVE" "$AWS_CLI_URL"
    unzip -q -d "$TMPDIR" "$AWS_CLI_ARCHIVE"
    $SUDO "${TMPDIR}/aws/install" >/dev/null
    echo
    echo 'AWS CLI installed successfully.'
}

configure_awscli() {
    if ! [[ -f $HOME/.aws/credentials ]]; then
        echo
        aws configure
    fi
}

install_credentials_helper() {
    AWS_ECR_CRED_HLPR_BIN="/usr/local/bin/${AWS_ECR_CRED_HLPR_URL##*/}"
    test -x "$AWS_ECR_CRED_HLPR_BIN" && return 0
    __apt_install_missing wget
    $SUDO wget -q -O "$AWS_ECR_CRED_HLPR_BIN" "$AWS_ECR_CRED_HLPR_URL"
    $SUDO chmod +x "$AWS_ECR_CRED_HLPR_BIN"
}

configure_credentials_helper() {
    __apt_install_missing jq
    if ! [[ -f $DOCKER_CONFIG ]]; then
        # shellcheck disable=SC2174
        mkdir -m 700 -p "${DOCKER_CONFIG%/*}"
        echo '{}' > "$DOCKER_CONFIG"
    fi
    CONFIG_JSON=$(jq -M --arg credsStore ecr-login \
        '. + {credsStore: $credsStore}' < "$DOCKER_CONFIG")
    echo "$CONFIG_JSON" >| "$DOCKER_CONFIG"
}

# Make sure to do cleanup even if the script exits abnormally
trap 'exit 1' HUP INT PIPE QUIT TERM
trap '__exit_cleanup' EXIT

# Use sudo when necessary
SUDO=sudo
if [[ $(id -u) == '0' ]] && ! __check_command_exists "$SUDO"; then
    SUDO=''
fi

install_awscli
configure_awscli
install_credentials_helper
configure_credentials_helper

aws ecr describe-repositories > /dev/null
echo
echo "AWS ECR credentials helper for Docker is installed and configured."