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# Stage 0 ─ builder：CUDA 12.6.1 + nvcc/gcc，编译本地 sglang 源码
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ARG CUDA_VERSION=12.6.1
ARG CUINDEX=126          # 12.6.x ⇒ cu126
FROM nvidia/cuda:${CUDA_VERSION}-devel-ubuntu22.04 AS builder

ENV DEBIAN_FRONTEND=noninteractive PYTHONUNBUFFERED=1 LANG=C.UTF-8 LC_ALL=C.UTF-8

RUN apt-get update && apt-get install -y --no-install-recommends \
        python3 python3-pip python3-distutils build-essential git ca-certificates && \
    python3 -m pip install --no-cache-dir --upgrade pip setuptools wheel

# ── ① 下载官方 PyTorch / TorchVision wheel ────────────────────────────────
RUN python3 -m pip download --no-deps \
        --dest /tmp/wheels \
        --index-url https://download.pytorch.org/whl/cu${CUINDEX} \
        torch==2.7.1 torchvision==0.22.1

# ── ② 下载 flashinfer cu126 / torch-2.7 wheel（只下载，不安装）─────────────
RUN python3 -m pip download --no-deps \
        --dest /tmp/wheels \
        --find-links https://flashinfer.ai/whl/cu${CUINDEX}/torch2.7/flashinfer-python \
        flashinfer-python

# ── ③ 安装前两步 wheel（为后面编译 sglang 做依赖）──────────────────────
RUN python3 -m pip install --no-cache-dir /tmp/wheels/torch-2.7.1+cu${CUINDEX}*.whl \
                           /tmp/wheels/torchvision-0.22.1+cu${CUINDEX}*.whl \
                           /tmp/wheels/flashinfer_python-*-cu${CUINDEX}_torch27*.whl

# ── ④ COPY 本地 sglang 源码并编译成 wheel ─────────────────────────────────
COPY ./sglang /sgl-workspace/sglang
WORKDIR /sgl-workspace/sglang/python
RUN python3 -m pip wheel '.[srt,openai]' --no-deps -w /tmp/wheels

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# Stage 1 ─ runtime：极简镜像，只离线安装 wheel
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ARG CUDA_VERSION=12.6.1
FROM nvidia/cuda:${CUDA_VERSION}-runtime-ubuntu22.04

ENV DEBIAN_FRONTEND=noninteractive PYTHONUNBUFFERED=1 LANG=C.UTF-8 LC_ALL=C.UTF-8

RUN apt-get update && apt-get install -y --no-install-recommends \
        python3 python3-pip python3-distutils ca-certificates && \
    rm -rf /var/lib/apt/lists/* && \
    python3 -m pip install --no-cache-dir --upgrade pip

# ── 把 builder 产出的所有 wheel（一共 4~5 个）拷贝进来并安装 ───────────
COPY --from=builder /tmp/wheels /tmp/wheels
RUN python3 -m pip install --no-cache-dir /tmp/wheels/* && rm -rf /tmp/wheels

# ── 仅打印帮助，CPU 机器也能跑 ─────────────────────────────────────────────
CMD ["python3", "-m", "sglang.launch_server", "--help"]