Automated Deployment Script for Java Applications using Docker and Docker Compose

#!/bin/bash

# Capture the start time
start_time=$(date +%s)
echo "$(date +'%H:%M:%S')"

# Function to be executed on exit, interrupt, or termination
on_exit() {
    # Capture the end time
    end_time=$(date +%s)

    # Calculate the elapsed time
    elapsed_time=$(( end_time - start_time ))

    # Convert elapsed time to hours, minutes, and seconds
    hours=$(( elapsed_time / 3600 ))
    minutes=$(( (elapsed_time % 3600) / 60 ))
    seconds=$(( elapsed_time % 60 ))

    # Print the elapsed time in HH:MM:SS format
    printf "Total time: %02d:%02d:%02d\n" $hours $minutes $seconds
}
trap on_exit EXIT
trap on_exit INT
trap on_exit TERM

# Configurable variables
PROJECT_DIR="/path/to/your/project"  # Path to your project directory
DOCKER_BUILD_DIR="/path/to/docker/build/dir"  # Directory where Dockerfile and docker-compose.yaml are located
WAR_FILE_NAME="your-application.war"  # Name of your WAR file
DOCKER_IMAGE_NAME="your-docker-image-name"
SMTP_HOST="smtp.your-email-provider.com"
SMTP_PORT="587"
SMTP_USERNAME="your-email@example.com"
SMTP_PASSWORD="your-email-password"
SENDER_NAME="Deployment info"
SENDER_EMAIL="$SMTP_USERNAME"
RECIPIENT_EMAILS=("recipient1@example.com" "recipient2@example.com")
EMAIL_SUBJECT="Deployment Log"

# Function to send email
send_email() {
    local message_content="$1"
    local recipients=("${@:2}")

    for recipient in "${recipients[@]}"; do
        echo "Sending email to: $recipient"

        local email_data=$(cat <<EOF
From: "$SENDER_NAME" <$SENDER_EMAIL>
To: $recipient
Subject: $EMAIL_SUBJECT
Content-Type: text/plain; charset=utf-8

$message_content
EOF
)

        echo -e "$email_data" | curl -s --url "smtp://$SMTP_HOST:$SMTP_PORT" \
          --ssl-reqd \
          --mail-from "$SENDER_EMAIL" \
          --mail-rcpt "$recipient" \
          --user "$SMTP_USERNAME:$SMTP_PASSWORD" \
          --upload-file - \
          --insecure 2>&1
    done
}

# Function to roll back to the previous version
rollback() {
    echo "Rolling back to the previous version..."
    docker rmi -f "$DOCKER_IMAGE_NAME:v1"
    docker tag "$DOCKER_IMAGE_NAME:rollback" "$DOCKER_IMAGE_NAME:v1"
    docker-compose -f "$DOCKER_BUILD_DIR/docker-compose.yaml" up -d
    echo "Rollback completed."
}

# Function to clean up old Docker images
cleanup_old_images() {
    echo "Cleaning up old Docker images..."

    # Get the list of rollback images sorted by creation date
    image_list=$(docker images --filter=reference="$DOCKER_IMAGE_NAME:rollback-*" --format "{{.ID}} {{.Repository}}:{{.Tag}}" | sort -r -k3)
    image_count=$(echo "$image_list" | wc -l)

    # Keep only the 2 latest rollback images
    if [ "$image_count" -gt 2 ]; then
        echo "$image_list" | tail -n +3 | awk '{ print $1 }' | xargs docker rmi -f
    fi

    # Prune dangling images
    docker image prune -f
}

# Pull the latest changes from the repository
git -C "$PROJECT_DIR" pull origin main

# Check if there are new changes
if [[ $(git -C "$PROJECT_DIR" log -1 --pretty=%H) != $(cat "$PROJECT_DIR/last_commit.txt") ]]; then
    echo "-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-"
    echo "Starting time: $(date +'%d-%m-%Y %I:%M:%S %p')"

    # Build the project and create the WAR file
    mvn -f "$PROJECT_DIR" clean package -Dmaven.test.skip=true > /dev/null

    # Move the WAR file to the Docker build directory
    mv "$PROJECT_DIR/target/$WAR_FILE_NAME" "$DOCKER_BUILD_DIR"

    # Stop the current Docker containers
    docker-compose -f "$DOCKER_BUILD_DIR/docker-compose.yaml" down

    # Tag the current version as rollback
    docker tag "$DOCKER_IMAGE_NAME:v1" "$DOCKER_IMAGE_NAME:rollback"

    # Build and start the new Docker containers
    docker-compose -f "$DOCKER_BUILD_DIR/docker-compose.yaml" build
    docker-compose -f "$DOCKER_BUILD_DIR/docker-compose.yaml" up -d

    start_time=$(date +%s)

    echo "Checking application logs..."
    while true; do
        if docker-compose -f "$DOCKER_BUILD_DIR/docker-compose.yaml" logs --tail=10 | grep -q "Started Application in"; then
            echo "Application started successfully."
            break
        fi

        current_time=$(date +%s)
        elapsed_time=$((current_time - start_time))

        if [ "$elapsed_time" -gt 300 ]; then
            echo "Application did not start within 5 minutes. Printing logs and rolling back..."
            docker-compose -f "$DOCKER_BUILD_DIR/docker-compose.yaml" logs --tail=100
            # Send email with logs content to multiple recipients
            logs_content=$(docker-compose -f "$DOCKER_BUILD_DIR/docker-compose.yaml" logs --tail=100)
            send_email "Deployment failed. Logs:\n\n$logs_content" "${RECIPIENT_EMAILS[@]}"
            rollback
            exit 1
        fi

        sleep 5
    done

    # Tag rollback image with timestamp if deployment is successful
    docker tag "$DOCKER_IMAGE_NAME:rollback" "$DOCKER_IMAGE_NAME:rollback-$(date +%Y%m%d%H%M%S)"

    cleanup_old_images

    commit_hash=$(git -C "$PROJECT_DIR" log -1 --pretty=%H)
    echo "$commit_hash"
    echo "$commit_hash" > "$PROJECT_DIR/last_commit.txt"
    echo "Ending Time: $(date +'%d-%m-%Y %I:%M:%S %p')"
fi

version: '3.8'

services:
  app:
    image: your-docker-image-name:v1
    build:
      context: .
      dockerfile: Dockerfile
    ports:
      - "8080:8080"
    environment:
      - SPRING_PROFILES_ACTIVE=prod
    volumes:
      - ./logs:/logs
    restart: always

  db:
    image: postgres:13
    environment:
      POSTGRES_DB: your_database
      POSTGRES_USER: your_user
      POSTGRES_PASSWORD: your_password
    volumes:
      - postgres_data:/var/lib/postgresql/data
    restart: always

volumes:
  postgres_data:

# Use an official Tomcat image as the base image
FROM tomcat:9.0-jdk11

# Add a volume pointing to /tmp
VOLUME /tmp

# The application's jar file
ARG WAR_FILE=your-application.war

# Add the application's war to Tomcat's webapps
ADD ${WAR_FILE} /usr/local/tomcat/webapps/

# Run the jar file
ENTRYPOINT ["catalina.sh", "run"]