A Docker Image Build and EC2 Copy Script - v0.5

docker-build-copy.sh

#!/bin/bash
#
# A Docker Image Build and EC2 Copy Script for macOS
# Updated: 4/4/2024
#

# Logging function
log() {
    local log_level="${1}"
    local message="${2}"
    local timestamp=$(date "+%Y-%m-%d %H:%M:%S")
    
    # Color codes for different log levels
    local COLOR_OFF="\033[0m"
    local GREEN="\033[0;32m"
    local YELLOW="\033[0;33m"
    local RED="\033[0;31m"
    local BLUE="\033[0;34m"
    
    case "${log_level}" in
        "INFO")
            echo -e "${GREEN}[${timestamp}] [INFO]${COLOR_OFF} ${message}"
            ;;
        "WARN")
            echo -e "${YELLOW}[${timestamp}] [WARN]${COLOR_OFF} ${message}" >&2
            ;;
        "ERROR")
            echo -e "${RED}[${timestamp}] [ERROR]${COLOR_OFF} ${message}" >&2
            ;;
        "DEBUG")
            echo -e "${BLUE}[${timestamp}] [DEBUG]${COLOR_OFF} ${message}"
            ;;
        *)
            echo -e "[${timestamp}] ${message}"
            ;;
    esac
}

# Configuration Variables (MODIFY THESE)
IMAGE_NAME="your-image-name"
IMAGE_TAG="v1.0"
EC2_USER="ec2-user"
EC2_HOST="your-ec2-instance-public-dns"
EC2_KEY_PATH="${HOME}/.ssh/your-ec2-key.pem"
DOCKERFILE_PATH="."  # Path to directory containing Dockerfile

# Error handling function
error_exit() {
    log "ERROR" "$1"
    exit 1
}

# Dependency check function (macOS compatible)
check_dependencies() {
    log "INFO" "Checking system dependencies..."
    
    # Check Docker
    if ! command -v docker &> /dev/null; then
        error_exit "Docker is not installed. Please install Docker Desktop for macOS."
    fi
    log "DEBUG" "Docker is installed: $(docker --version)"

    # Check SSH (typically pre-installed on macOS)
    if ! command -v ssh &> /dev/null; then
        error_exit "SSH is not available. Ensure you have the latest macOS updates."
    fi
    log "DEBUG" "SSH is available"

    # Check SCP
    if ! command -v scp &> /dev/null; then
        error_exit "SCP is not available. Ensure you have the latest macOS updates."
    fi
    log "DEBUG" "SCP is available"
}

# Main script execution
main() {
    # Ensure script fails if any command fails
    set -e

    # Check dependencies
    check_dependencies

    # Validate key file exists and has correct permissions
    if [[ ! -f "${EC2_KEY_PATH}" ]]; then
        error_exit "SSH key not found at ${EC2_KEY_PATH}"
    fi

    # Secure key file permissions (macOS and Linux compatible)
    chmod 600 "${EC2_KEY_PATH}"
    log "INFO" "Secured SSH key permissions"

    # Build Docker image
    log "INFO" "Building Docker image: ${IMAGE_NAME}:${IMAGE_TAG}"
    docker build -t "${IMAGE_NAME}:${IMAGE_TAG}" "${DOCKERFILE_PATH}" || error_exit "Docker build failed"
    log "INFO" "Docker image build completed successfully"

    # Create temporary directory (macOS compatible)
    TEMP_DIR=$(mktemp -d -t docker-transfer-XXXXXXXXXX)
    log "DEBUG" "Using temporary directory: ${TEMP_DIR}"

    # Save the Docker image to a tar file
    log "INFO" "Saving Docker image to tar file"
    docker save -o "${TEMP_DIR}/${IMAGE_NAME}-${IMAGE_TAG}.tar" "${IMAGE_NAME}:${IMAGE_TAG}" || error_exit "Docker save failed"
    log "DEBUG" "Image saved: ${TEMP_DIR}/${IMAGE_NAME}-${IMAGE_TAG}.tar"

    # Copy the image to EC2 instance
    log "INFO" "Copying Docker image to EC2 instance"
    scp -o StrictHostKeyChecking=no \
        -i "${EC2_KEY_PATH}" \
        "${TEMP_DIR}/${IMAGE_NAME}-${IMAGE_TAG}.tar" \
        "${EC2_USER}@${EC2_HOST}:~/" || error_exit "SCP transfer failed"
    log "INFO" "Docker image successfully transferred to EC2"

    # SSH into EC2 and load the Docker image
    log "INFO" "Loading Docker image on EC2 instance"
    ssh -o StrictHostKeyChecking=no \
        -i "${EC2_KEY_PATH}" "${EC2_USER}@${EC2_HOST}" << EOF
docker load -i ~/"${IMAGE_NAME}-${IMAGE_TAG}.tar"
rm ~/"${IMAGE_NAME}-${IMAGE_TAG}.tar"
docker images | grep "${IMAGE_NAME}"
EOF
    log "INFO" "Docker image loaded and verified on EC2"

    # Clean up temporary files
    rm -rf "${TEMP_DIR}"
    log "INFO" "Local temporary files cleaned up"

    log "INFO" "🚀 Docker image successfully built and copied to EC2!"
}

# Trap to ensure cleanup happens even if script is interrupted
trap 'log "WARN" "Script interrupted. Performing cleanup..."; rm -rf "${TEMP_DIR}" 2>/dev/null' SIGINT SIGTERM ERR

# Run the main function
main