DigitalOcean Droplet Deployment Skill

This skill provides comprehensive deployment lifecycle management for applications deployed directly to DigitalOcean droplets using doctl CLI and systemd service management.

Overview

The deployment lifecycle consists of five phases:

1. Pre-Deployment Validation - Application readiness, dependencies, configuration
2. Secret Management - Secure environment variable handling via doctl
3. Deployment - Code transfer, dependency installation, service setup
4. Service Management - Systemd service configuration and control
5. Post-Deployment Verification - Health checks, service status validation

Supported Application Types

• Python: Flask, FastAPI, Django, background workers, scripts
• Node.js: Express, Fastify, Next.js (standalone), background workers
• Generic: Any application that can run as a systemd service

Available Scripts

1. Application Validation

Script: scripts/validate-app.sh <app-path>

Purpose: Validates application is ready for deployment

Checks:

• Application entry point exists (server.py, app.py, index.js, server.js)
• Dependencies declared (requirements.txt, package.json)
• Environment configuration (.env.example present)
• No hardcoded secrets
• Valid Python/Node.js syntax
• Port configuration

Usage:

# Validate Python app
./scripts/validate-app.sh /path/to/python-app

# Validate Node.js app
./scripts/validate-app.sh /path/to/nodejs-app

# Verbose mode
VERBOSE=1 ./scripts/validate-app.sh .

Exit Codes:

• 0: Validation passed
• 1: Validation failed (must fix before deployment)

2. Deploy to Droplet

Script: scripts/deploy-to-droplet.sh <app-path> <droplet-ip> <app-name>

Purpose: Deploys application to DigitalOcean droplet

Actions:

• Validates doctl authentication
• Creates application directory on droplet
• Transfers code via rsync
• Creates secure environment file
• Installs dependencies
• Sets up systemd service
• Starts and enables service
• Verifies service is running

Usage:

# Deploy Python app
./scripts/deploy-to-droplet.sh /path/to/app 137.184.196.101 myapp

# Deploy with custom port
PORT=8080 ./scripts/deploy-to-droplet.sh /path/to/app 137.184.196.101 myapp

# Deploy with specific Python version
PYTHON_VERSION=3.11 ./scripts/deploy-to-droplet.sh /path/to/app 137.184.196.101 myapp

# Deploy Node.js app
APP_TYPE=nodejs ./scripts/deploy-to-droplet.sh /path/to/app 137.184.196.101 myapp

Environment Variables:

• APP_TYPE: python or nodejs (auto-detected if not specified)
• PORT: Port to run on (default: 8000)
• PYTHON_VERSION: Python version (default: 3.11)
• NODE_VERSION: Node.js version (default: 20)
• SERVICE_USER: User to run service as (default: root)
• APP_DIR: Target directory on droplet (default: /opt/<app-name>)

Required Environment Variables (must be set before running):

• All environment variables from .env.example must be provided
• Script will prompt for missing variables or use .env file if present

Exit Codes:

• 0: Deployment successful
• 1: Deployment failed

3. Update Secrets

Script: scripts/update-secrets.sh <droplet-ip> <app-name>

Purpose: Updates environment variables without redeploying code

Actions:

• Prompts for updated environment variables
• Securely updates .env file on droplet
• Restarts service to apply changes
• Verifies service restarted successfully

Usage:

# Update secrets interactively
./scripts/update-secrets.sh 137.184.196.101 myapp

# Update from local .env file
ENV_FILE=.env.production ./scripts/update-secrets.sh 137.184.196.101 myapp

Exit Codes:

• 0: Secrets updated successfully
• 1: Update failed

4. Health Check

Script: scripts/health-check.sh <droplet-ip> <app-name> [port]

Purpose: Validates deployment health and service status

Checks:

• Systemd service status (active/running)
• HTTP endpoint responding (if applicable)
• Process running with correct user
• Log file accessible
• Port listening
• Memory usage
• CPU usage

Usage:

# Check service health
./scripts/health-check.sh 137.184.196.101 myapp

# Check with custom port
./scripts/health-check.sh 137.184.196.101 myapp 8080

# Continuous monitoring (runs every 30s)
MONITOR=true ./scripts/health-check.sh 137.184.196.101 myapp

Exit Codes:

• 0: All health checks passed
• 1: One or more health checks failed

5. Manage Deployment

Script: scripts/manage-deployment.sh <action> <droplet-ip> <app-name>

Purpose: Manage deployed application lifecycle

Actions:

• start: Start the service
• stop: Stop the service
• restart: Restart the service
• status: Show service status
• logs: View service logs
• rollback: Rollback to previous version
• remove: Remove deployment completely

Usage:

# Restart service
./scripts/manage-deployment.sh restart 137.184.196.101 myapp

# View logs (last 100 lines)
./scripts/manage-deployment.sh logs 137.184.196.101 myapp

# View logs (follow)
FOLLOW=true ./scripts/manage-deployment.sh logs 137.184.196.101 myapp

# Rollback to previous version
./scripts/manage-deployment.sh rollback 137.184.196.101 myapp

# Remove deployment
./scripts/manage-deployment.sh remove 137.184.196.101 myapp

Available Templates

1. Systemd Service Template

File: templates/systemd-service.template

Purpose: Systemd service file template for any application type

Variables:

• {{APP_NAME}}: Application name
• {{APP_DIR}}: Application directory path
• {{APP_USER}}: User to run service as
• {{APP_TYPE}}: python or nodejs
• {{ENTRY_POINT}}: Main file (server.py, index.js, etc.)
• {{PORT}}: Port to run on

Example:

[Unit]
Description={{APP_NAME}} Application
After=network.target

[Service]
Type=simple
User={{APP_USER}}
WorkingDirectory={{APP_DIR}}
Environment="PATH=/usr/local/bin:/usr/bin:/bin"
EnvironmentFile={{APP_DIR}}/.env
ExecStart={{EXEC_START}}
Restart=always
RestartSec=10

[Install]
WantedBy=multi-user.target

2. Environment File Template

File: templates/.env.template

Purpose: Secure environment variable template

Example:

# Application Configuration
PORT=8000
HOST=0.0.0.0
NODE_ENV=production

# API Keys (NEVER commit these)
API_KEY=your_api_key_here
DATABASE_URL=your_database_url_here

# Optional
LOG_LEVEL=info

3. Deployment Configuration

File: templates/deployment-config.json

Purpose: Track deployments to droplets

Structure:

{
  "version": "1.0.0",
  "deployments": [
    {
      "id": "deployment-uuid-here",
      "appName": "myapp",
      "appType": "python",
      "dropletIp": "137.184.196.101",
      "port": 8000,
      "appDirectory": "/opt/myapp",
      "serviceUser": "root",
      "status": "active",
      "deployedAt": "2025-11-02T18:30:00Z",
      "deployedBy": "user@example.com",
      "version": "1.0.0",
      "metadata": {
        "gitCommit": "abc123",
        "gitBranch": "main",
        "pythonVersion": "3.11",
        "entryPoint": "server.py"
      },
      "environmentVariables": [
        {
          "name": "API_KEY",
          "isSet": true,
          "source": "doctl-secrets"
        },
        {
          "name": "PORT",
          "isSet": true,
          "source": "deployment-script"
        }
      ],
      "health": {
        "lastCheck": "2025-11-02T18:35:00Z",
        "status": "healthy",
        "uptime": "5m 30s",
        "memoryUsage": "45MB",
        "cpuUsage": "2%"
      }
    }
  ],
  "metadata": {
    "lastUpdated": "2025-11-02T18:35:00Z",
    "totalDeployments": 1,
    "activeDeployments": 1
  }
}

4. Deployment Checklist

File: templates/deployment-checklist.md

Purpose: Pre-deployment checklist

Contents:

• doctl installed and authenticated
• Droplet accessible via SSH
• Application validated locally
• All required environment variables identified
• .env.example created with all required variables
• No hardcoded secrets in code
• Dependencies pinned in requirements.txt/package.json
• Health endpoint implemented (optional but recommended)
• Logging configured
• Error handling implemented

Examples

Example 1: Python FastAPI App

File: examples/python-fastapi-deployment.md

Shows:

• Complete FastAPI app deployment
• Systemd service setup
• Environment variable management
• Health check endpoint
• Deployment verification

Example 2: Node.js Express App

File: examples/nodejs-express-deployment.md

Shows:

• Express app deployment
• PM2 vs systemd comparison
• Port configuration
• Log management
• Deployment troubleshooting

Example 3: Background Worker

File: examples/background-worker-deployment.md

Shows:

• Python background worker deployment
• No HTTP endpoint
• Systemd service configuration
• Log-based health checks
• Process monitoring

Deployment Workflow

Initial Deployment

1. Validate Application:

   ./scripts/validate-app.sh /path/to/app
   

2. Deploy to Droplet:

   ./scripts/deploy-to-droplet.sh /path/to/app 137.184.196.101 myapp
   

3. Verify Health:

   ./scripts/health-check.sh 137.184.196.101 myapp
   

Update Deployment

1. Update Code:

   ./scripts/deploy-to-droplet.sh /path/to/app 137.184.196.101 myapp
   

2. Verify Health:

   ./scripts/health-check.sh 137.184.196.101 myapp
   

Update Secrets Only

1. Update Secrets:

   ./scripts/update-secrets.sh 137.184.196.101 myapp
   

2. Verify Service Restarted:

   ./scripts/manage-deployment.sh status 137.184.196.101 myapp
   

Security Best Practices

1. Never Hardcode Secrets: Always use environment variables
2. Use .env Files: Store secrets securely on droplet
3. Restrict File Permissions: .env files should be 600 (readable only by service user)
4. Rotate Secrets Regularly: Use update-secrets.sh to rotate API keys
5. Use Secure Transfer: Scripts use doctl SSH for secure transfers
6. Validate Before Deploy: Always run validation before deployment
7. Monitor Logs: Regularly check logs for security issues

Troubleshooting

Service Won't Start

# Check service status
./scripts/manage-deployment.sh status 137.184.196.101 myapp

# View logs
./scripts/manage-deployment.sh logs 137.184.196.101 myapp

# Common issues:
# - Missing environment variables
# - Port already in use
# - Permission issues
# - Syntax errors in code

Deployment Failed

# Check doctl authentication
doctl auth list

# Verify droplet accessible
doctl compute ssh 137.184.196.101 --ssh-command "echo 'Connection successful'"

# Re-run with verbose output
VERBOSE=1 ./scripts/deploy-to-droplet.sh /path/to/app 137.184.196.101 myapp

Health Check Failures

# Check service is running
./scripts/manage-deployment.sh status 137.184.196.101 myapp

# Check logs for errors
./scripts/manage-deployment.sh logs 137.184.196.101 myapp

# Verify port is listening
doctl compute ssh 137.184.196.101 --ssh-command "netstat -tlnp | grep <port>"

Integration with Dev Lifecycle

This skill integrates with:

• /deployment:prepare - Pre-deployment validation
• /deployment:deploy - Execute deployment
• /deployment:validate - Post-deployment verification
• /deployment:rollback - Rollback to previous version

Next Steps

After creating the skill, you should also create:

• digitalocean-app-deployment - For App Platform deployments
• Integration with deployment plugin commands
• Agent for automated deployment orchestration