Docker Deployment Infrastructure Setup

Workflow

Step 1: Analyze Project Structure

First, understand the project:

• Identify all services that need containers
• Identify third-party dependencies (databases, caches, message queues)
• Determine port mappings and environment variables
• Check for existing Docker configurations

Step 2: Create Environment Configuration

Create .env.template with all configurable values:

# Registry Configuration
REGISTRY_PREFIX=localhost:5000  # Change for production: registry.example.com

# Application Versions
APP_VERSION=1.0.0

# Service Configuration
SERVICE_A_PORT=8080
SERVICE_B_PORT=8081

# Database Configuration  
DB_VERSION=15.4
DB_NAME=myapp
DB_USER=myuser
DB_PASSWORD=changeme
DB_PORT=5432

# Cache Configuration
REDIS_VERSION=7.2.3
REDIS_PORT=6379

# Environment
ENV=local  # local, staging, production

Key rules:

• Always pin versions: Use 15.4 not latest or 15
• Make ports configurable: Don't hardcode in docker-compose
• Separate secrets: Database passwords, API keys in .env (not in template)
• Document every variable: Add comments explaining usage

Step 3: Create Dockerfiles

For each application service, create optimized Dockerfiles:

Multi-stage build example:

# Stage 1: Build
FROM node:20.11.0-alpine AS builder
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production
COPY . .
RUN npm run build

# Stage 2: Production
FROM node:20.11.0-alpine
WORKDIR /app
COPY --from=builder /app/dist ./dist
COPY --from=builder /app/node_modules ./node_modules
COPY package.json ./
EXPOSE 3000
USER node
CMD ["node", "dist/main.js"]

Requirements:

• Use specific versions only (e.g., node:20.11.0-alpine, not node:alpine)
• Use multi-stage builds to minimize image size
• Run as non-root user when possible
• Include only necessary files (use .dockerignore)

Step 4: Create Docker Compose Configuration

Create the main docker-compose.yml using registry prefix pattern: