1# Dockerfile Generation
2 
3Create Dockerfiles for containerized services.
4 
5## When to Containerize
6 
7| Include | Exclude |
8|---------|---------|
9| APIs, microservices | Static websites (use Static Web Apps) |
10| Web apps (SSR) | Azure Functions (native deploy) |
11| Background workers | Database services |
12| Message processors | Logic Apps |
13 
14## Templates by Language
15 
16### Node.js
17 
18```dockerfile
19FROM node:22-slim
20WORKDIR /app
21COPY package*.json ./
22RUN npm ci --only=production
23COPY . .
24EXPOSE 3000
25CMD ["node", "index.js"]
26```
27 
28### Python
29 
30```dockerfile
31FROM python:3.13-slim
32WORKDIR /app
33COPY requirements.txt .
34RUN pip install --no-cache-dir -r requirements.txt
35COPY . .
36EXPOSE 8000
37CMD ["uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000"]
38```
39 
40### .NET
41 
42```dockerfile
43FROM mcr.microsoft.com/dotnet/aspnet:10.0 AS base
44WORKDIR /app
45EXPOSE 8080
46 
47FROM mcr.microsoft.com/dotnet/sdk:10.0 AS build
48WORKDIR /src
49COPY ["*.csproj", "./"]
50RUN dotnet restore
51COPY . .
52RUN dotnet publish -c Release -o /app/publish
53 
54FROM base AS final
55WORKDIR /app
56COPY --from=build /app/publish .
57ENTRYPOINT ["dotnet", "App.dll"]
58```
59 
60### Java
61 
62```dockerfile
63FROM eclipse-temurin:21-jdk-alpine AS build
64WORKDIR /app
65COPY . .
66RUN ./mvnw package -DskipTests
67 
68FROM eclipse-temurin:21-jre-alpine
69WORKDIR /app
70COPY --from=build /app/target/*.jar app.jar
71EXPOSE 8080
72ENTRYPOINT ["java", "-jar", "app.jar"]
73```
74 
75### Go
76 
77```dockerfile
78FROM golang:1.22-alpine AS build
79WORKDIR /app
80COPY go.* ./
81RUN go mod download
82COPY . .
83RUN CGO_ENABLED=0 go build -o main .
84 
85FROM alpine:latest
86WORKDIR /app
87COPY --from=build /app/main .
88EXPOSE 8080
89CMD ["./main"]
90```
91 
92## .dockerignore
93 
94```
95.git
96node_modules
97__pycache__
98*.pyc
99.env
100.azure
101```
102 
103## Best Practices
104 
105- Use slim/alpine base images
106- Multi-stage builds for compiled languages
107- Non-root user when possible
108- Include health check endpoint in app
109 
110## Runtime-Specific Configuration
111 
112For production settings specific to each runtime:
113 
114| Runtime | Reference |
115|---------|-----------| 
116| Node.js/Express | [runtimes/nodejs.md](../../runtimes/nodejs.md) |
117