Docker 部署

使用 Docker 容器化 Go 应用，简化部署和运维。

Dockerfile

多阶段构建

# 构建阶段
FROM golang:1.21-alpine AS builder

# 安装依赖
RUN apk add --no-cache git ca-certificates

WORKDIR /app

# 复制依赖文件
COPY go.mod go.sum ./
RUN go mod download

# 复制源码
COPY . .

# 构建
RUN CGO_ENABLED=0 go build -ldflags="-s -w" -o myapp ./cmd/myapp

# 运行时镜像
FROM alpine:latest

RUN apk --no-cache add ca-certificates tzdata

WORKDIR /root/

# 从构建阶段复制
COPY --from=builder /app/myapp .
COPY --from=builder /app/configs ./configs

# 创建非 root 用户
RUN addgroup -g 1000 appuser && \
    adduser -D -u 1000 -G appuser appuser && \
    chown -R appuser:appuser /root

USER appuser

EXPOSE 8080

CMD ["./myapp"]

最小化镜像

# 使用 distroless 镜像
FROM golang:1.21-alpine AS builder

WORKDIR /app
COPY go.mod go.sum ./
RUN go mod download
COPY . .
RUN CGO_ENABLED=0 go build -o myapp ./cmd/myapp

# distroless 更小更安全
FROM gcr.io/distroless/static-debian11

COPY --from=builder /app/myapp /myapp
COPY --from=builder /app/configs /configs

EXPOSE 8080

ENTRYPOINT ["/myapp"]

Docker Compose

基本配置

version: '3.8'

services:
  app:
    build:
      context: .
      dockerfile: Dockerfile
    ports:
      - "8080:8080"
    environment:
      - APP_SERVER_HOST=0.0.0.0
      - APP_SERVER_PORT=8080
      - APP_DB_HOST=db
      - APP_DB_PORT=3306
    depends_on:
      - db
      - redis
    restart: unless-stopped

  db:
    image: mysql:8.0
    environment:
      - MYSQL_ROOT_PASSWORD=secret
      - MYSQL_DATABASE=myapp
    volumes:
      - mysql_data:/var/lib/mysql
    restart: unless-stopped

  redis:
    image: redis:7-alpine
    volumes:
      - redis_data:/data
    restart: unless-stopped

volumes:
  mysql_data:
  redis_data:

开发环境

version: '3.8'

services:
  app:
    build:
      context: .
      target: builder
    volumes:
      - .:/app
    ports:
      - "8080:8080"
    environment:
      - APP_ENV=development
    command: go run ./cmd/myapp

构建优化

依赖缓存

# ✅ 利用 Docker 层缓存
FROM golang:1.21-alpine AS builder

WORKDIR /app

# 先复制依赖文件，利用缓存
COPY go.mod go.sum ./
RUN go mod download

# 再复制源码
COPY . .

# 构建
RUN CGO_ENABLED=0 go build -o myapp ./cmd/myapp

并行构建

# 并行下载和编译
RUN go mod download && \
    go build -ldflags="-s -w" -o myapp ./cmd/myapp

健康检查

Dockerfile 健康检查

HEALTHCHECK --interval=30s --timeout=3s \
  CMD wget --no-verbose --tries=1 --spider http://localhost:8080/health || exit 1

Compose 健康检查

services:
  app:
    healthcheck:
      test: ["CMD", "wget", "--spider", "-q", "http://localhost:8080/health"]
      interval: 30s
      timeout: 10s
      retries: 3
      start_period: 40s

最佳实践

Docker 建议

1. 多阶段构建 - 减小镜像大小
2. 非 root 用户 - 提高安全性
3. 健康检查 - 监控应用状态
4. 资源限制 - 防止资源耗尽
5. 日志配置 - 使用 stdout/stderr

# ✅ 好的模式
FROM golang:1.21-alpine AS builder
# ... 构建逻辑 ...

FROM alpine:latest
RUN adduser -D -u 1000 appuser
USER appuser
# ... 运行配置 ...

总结

方面	关键点
多阶段	减小最终镜像大小
alpine	使用轻量级基础镜像
健康检查	监控应用状态
非 root	提高安全性
日志	输出到标准输出

代码规范 → 部署运维