distroless容器部署Python应用出现enchant C库未找到错误如何解决

你只将Python虚拟环境拷贝到了distroless镜像中，但libenchant的C动态库是通过apt安装在debian基础镜像的系统路径下，并未包含在/venv目录内，因此distroless环境运行时无法找到对应的依赖库。

你需要将build阶段安装的libenchant相关动态库、配置文件同步拷贝到distroless镜像中，修改后的Dockerfile如下：

FROM debian:buster-slim AS build
RUN apt-get update && \
    apt-get install --no-install-suggests --no-install-recommends --yes python3-venv gcc libpython3-dev && \
    python3 -m venv /venv && \
    /venv/bin/pip install --upgrade pip

RUN apt-get update -y

WORKDIR /venv/
RUN apt-get install libre2-dev git wget vim python3-enchant libenchant-dev -y
RUN apt-get install libre2-5
RUN apt-get install enchant -y

FROM build AS build-venv
COPY requirements.txt /requirements.txt
RUN /venv/bin/pip install --disable-pip-version-check -r /requirements.txt

FROM gcr.io/distroless/python3-debian10
COPY --from=build-venv /venv /venv
# 拷贝libenchant核心动态库
COPY --from=build-venv /usr/lib/x86_64-linux-gnu/libenchant.so* /usr/lib/x86_64-linux-gnu/
# 拷贝enchant组件配置与字典目录
COPY --from=build-venv /usr/lib/x86_64-linux-gnu/enchant /usr/lib/x86_64-linux-gnu/enchant
COPY --from=build-venv /usr/share/enchant /usr/share/enchant

COPY . /app
WORKDIR /app
EXPOSE 6000
ENTRYPOINT ["/venv/bin/python3", "app.py"]

排查补充 #

如果修改后仍有依赖报错，可在build阶段执行以下命令查看pyenchant依赖的所有动态库，将缺失的库逐一拷贝到distroless镜像对应路径即可：
ldd /venv/lib/python3.7/site-packages/enchant/_enchant*.so

注：如果你的镜像运行在arm架构设备上，动态库路径前缀为/usr/lib/aarch64-linux-gnu/，可执行dpkg -L libenchant-dev | grep .so确认库文件实际存储路径。

内容的提问来源于stack exchange，提问作者Rakesh varma