# ============================================
# Multi-stage Dockerfile for gotest
# Stage 1: Build (Go 1.25)
# Stage 2: Runtime (minimal Alpine)
# ============================================

# ---- Build Stage ----
FROM golang:1.25-alpine AS builder

# 安装必要的构建工具
RUN apk add --no-cache git ca-certificates tzdata

WORKDIR /build

# 利用 Docker 层缓存：先拷贝依赖文件，再下载依赖
COPY go.mod go.sum ./
RUN go mod download

# 拷贝源代码
COPY . .

# 构建：CGO_ENABLED=0 纯静态二进制，适合 scratch/alpine
# 前端模板通过 //go:embed 已嵌入二进制
ENV CGO_ENABLED=0 GOOS=linux GOARCH=amd64
RUN go build -ldflags="-s -w" -o gotest .

# ---- Runtime Stage ----
FROM alpine:3.20

# 安装最小运行时依赖
RUN apk add --no-cache ca-certificates tzdata

# 设置时区
ENV TZ=Asia/Shanghai

# 创建非 root 用户运行
RUN addgroup -S app && adduser -S app -G app

# 创建数据和上传目录
RUN mkdir -p /app/data /app/uploads && chown -R app:app /app

WORKDIR /app

# 从构建阶段拷贝二进制和配置
COPY --from=builder /build/gotest .
COPY --from=builder /build/config.yaml .

# 切换非 root 用户
USER app

# 暴露端口
EXPOSE 8080

# 健康检查
HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
    CMD wget -q -O- http://localhost:8080/api/health || exit 1

# 启动
ENTRYPOINT ["./gotest"]