App Platform Deployment

What is App Platform?

App Platform is DigitalOcean's fully managed PaaS:

• Git-based deployments - Push to deploy
• Automatic scaling - Handle traffic spikes
• Free SSL - Managed certificates
• Built-in CI/CD - Build and deploy automatically
• Component-based - Services, workers, jobs, databases

Git Push → Build → Deploy → Scale
   │          │        │       │
   └── GitHub/GitLab   │       └── Automatic
              └── Buildpacks/Docker
                        └── App Platform

App Platform vs Droplets

Step 1: Prepare Your Application

Supported Runtimes

Node.js Requirements

json
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// package.json
{
  "name": "myapp",
  "scripts": {
    "start": "node server.js",
    "build": "npm run build"
  },
  "engines": {
    "node": "20.x"
  }
}

javascript
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// server.js - Use PORT environment variable
const port = process.env.PORT || 8080;
app.listen(port, '0.0.0.0', () => {
  console.log(`Server running on port ${port}`);
});

Python Requirements

txt
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# requirements.txt
flask==3.0.0
gunicorn==21.2.0

python
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# app.py
import os
from flask import Flask
app = Flask(__name__)

if __name__ == '__main__':
    port = int(os.environ.get('PORT', 8080))
    app.run(host='0.0.0.0', port=port)

Dockerfile (Custom)

dockerfile
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FROM node:20-alpine

WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production
COPY . .

ENV PORT=8080
EXPOSE 8080

CMD ["node", "server.js"]

Step 2: Create App Spec

Create .do/app.yaml in your repository:

Basic Web Service

yaml
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name: myapp
region: nyc

services:
  - name: web
    github:
      repo: username/myapp
      branch: main
      deploy_on_push: true
    build_command: npm run build
    run_command: npm start
    http_port: 8080
    instance_size_slug: basic-xxs
    instance_count: 1
    routes:
      - path: /

With Environment Variables

yaml
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name: myapp
region: nyc

services:
  - name: web
    github:
      repo: username/myapp
      branch: main
      deploy_on_push: true
    http_port: 8080
    instance_size_slug: basic-xs
    envs:
      - key: NODE_ENV
        value: production
      - key: DATABASE_URL
        scope: RUN_TIME
        type: SECRET
        value: ${db.DATABASE_URL}

With Database

yaml
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name: myapp
region: nyc

services:
  - name: web
    github:
      repo: username/myapp
      branch: main
    http_port: 8080
    instance_size_slug: basic-xs
    envs:
      - key: DATABASE_URL
        scope: RUN_TIME
        value: ${db.DATABASE_URL}

databases:
  - name: db
    engine: PG
    production: false

Static Site

yaml
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name: my-static-site
region: nyc

static_sites:
  - name: website
    github:
      repo: username/my-site
      branch: main
    build_command: npm run build
    output_dir: dist
    routes:
      - path: /

Worker (Background Jobs)

yaml
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name: myapp
region: nyc

services:
  - name: web
    github:
      repo: username/myapp
      branch: main
    http_port: 8080

workers:
  - name: worker
    github:
      repo: username/myapp
      branch: main
    run_command: npm run worker
    instance_size_slug: basic-xxs
    instance_count: 1

Scheduled Job

yaml
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name: myapp
region: nyc

jobs:
  - name: cleanup
    github:
      repo: username/myapp
      branch: main
    run_command: npm run cleanup
    kind: PRE_DEPLOY
    instance_size_slug: basic-xxs

Step 3: Deploy the App

Via CLI

bash
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# Create app from spec
doctl apps create --spec .do/app.yaml

# Get app ID
doctl apps list

# Update existing app
doctl apps update APP_ID --spec .do/app.yaml

Via Control Panel

1. Go to cloud.digitalocean.com/apps
2. Click Create App
3. Select source (GitHub, GitLab, Docker Hub)
4. Configure build settings
5. Add resources (database, etc.)
6. Configure environment variables
7. Click Create Resources

Step 4: Instance Sizes

Available Sizes

Choosing Size

• Basic: Shared CPU, good for low-traffic apps
• Professional: Dedicated CPU, for production workloads

Step 5: Environment Variables

In App Spec

yaml
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envs:
  # Plain text (visible)
  - key: NODE_ENV
    value: production

  # Secret (encrypted)
  - key: API_KEY
    type: SECRET
    value: your-api-key

  # Build-time only
  - key: NPM_TOKEN
    scope: BUILD_TIME
    type: SECRET
    value: token

  # Run-time only
  - key: DATABASE_URL
    scope: RUN_TIME
    value: ${db.DATABASE_URL}

  # Reference another component
  - key: REDIS_URL
    scope: RUN_TIME
    value: ${redis.REDIS_URL}

Via CLI

bash
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# List app environment
doctl apps get APP_ID --format Spec

# Update via spec
doctl apps update APP_ID --spec .do/app.yaml

Via Control Panel

1. App → Settings → App-Level Environment Variables
2. Or component-specific: Components → Service → Environment Variables

Step 6: Custom Domains

Add Domain

bash
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# Via Control Panel:
# App → Settings → Domains → Add Domain

DNS Configuration

Point your domain to App Platform:

Or use DigitalOcean DNS:

1. Add domain to your account
2. Update nameservers at registrar
3. App Platform manages records automatically

SSL Certificates

SSL is automatic and free:

• Let's Encrypt certificates
• Auto-renewal
• Force HTTPS option

Step 7: Scaling

Horizontal Scaling

yaml
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services:
  - name: web
    instance_count: 3
    instance_size_slug: professional-xs

Auto-Scaling

yaml
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services:
  - name: web
    instance_size_slug: professional-xs
    autoscaling:
      min_instance_count: 1
      max_instance_count: 10
      metrics:
        cpu:
          percent: 70

Manual Scaling

bash
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# Update instance count via spec
doctl apps update APP_ID --spec updated-spec.yaml

Step 8: Logs and Monitoring

View Logs

bash
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# Stream live logs
doctl apps logs APP_ID --follow

# Component-specific logs
doctl apps logs APP_ID web --follow

# Build logs
doctl apps logs APP_ID --type BUILD

# Deploy logs
doctl apps logs APP_ID --type DEPLOY

Via Control Panel

1. App → Runtime Logs (live)
2. App → Activity (deploy history)

Metrics

View in Control Panel:

• CPU usage
• Memory usage
• Request count
• Response time
• Bandwidth

Step 9: Deployments

Trigger Deployment

bash
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# Create new deployment
doctl apps create-deployment APP_ID

# Force rebuild
doctl apps create-deployment APP_ID --force-rebuild

Automatic Deployments

When deploy_on_push: true, pushing to the configured branch triggers deployment.

Rollback

1. App → Activity
2. Find previous deployment
3. Click Redeploy

Deployment Workflow

Push to main → Build starts → Tests run → Deploy → Health check
      │             │            │          │           │
      └─ Trigger    └─ Minutes   └─ CI      └─ Replace  └─ Verify

Step 10: Database Integration

Dev Database (Free)

yaml
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databases:
  - name: db
    engine: PG
    production: false  # Free dev database

Limited to:

• 1 GB storage
• Shared resources
• Good for development

Production Database

yaml
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databases:
  - name: db
    engine: PG
    production: true
    cluster_name: my-cluster
    db_name: myapp
    db_user: myuser

Or use existing Managed Database:

yaml
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services:
  - name: web
    envs:
      - key: DATABASE_URL
        scope: RUN_TIME
        type: SECRET
        value: "postgresql://user:pass@host:port/db?sslmode=require"

Complete Examples

Next.js Application

yaml
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name: nextjs-app
region: nyc

services:
  - name: web
    github:
      repo: username/nextjs-app
      branch: main
      deploy_on_push: true
    build_command: npm run build
    run_command: npm start
    http_port: 3000
    instance_size_slug: basic-xs
    envs:
      - key: NODE_ENV
        value: production

Full-Stack App

yaml
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name: fullstack-app
region: nyc

services:
  - name: api
    github:
      repo: username/myapp
      branch: main
    source_dir: /api
    build_command: npm run build
    run_command: npm start
    http_port: 8080
    instance_size_slug: professional-xs
    envs:
      - key: DATABASE_URL
        scope: RUN_TIME
        value: ${db.DATABASE_URL}
    routes:
      - path: /api

static_sites:
  - name: frontend
    github:
      repo: username/myapp
      branch: main
    source_dir: /frontend
    build_command: npm run build
    output_dir: dist
    envs:
      - key: VITE_API_URL
        value: ${api.PUBLIC_URL}/api
    routes:
      - path: /

databases:
  - name: db
    engine: PG
    production: true

Troubleshooting

Build Fails

bash
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# Check build logs
doctl apps logs APP_ID --type BUILD

Common issues:

• Missing dependencies in package.json
• Wrong Node.js version
• Build command error

App Won't Start

• Check run_command is correct
• Verify app listens on PORT environment variable
• Check runtime logs for errors

Database Connection Failed

• Verify DATABASE_URL is set correctly
• Check database is in same region
• Verify SSL mode if required

Deployment Stuck

bash
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# Cancel deployment
doctl apps create-deployment APP_ID --force-rebuild

# Or via Control Panel: Activity → Cancel