bash - 检查非守护进程 Docker 容器，在它完成运行后

Question

我有一个我创建的容器

# start
docker build -t cdt-tests .
docker run -it --name cdt-tests cdt-tests
# end => I want to inspect the container filesystem after it's done

因为它不是在分离模式下运行，我该如何检查容器？我想要做的是防止容器“自动关闭”，这样我就可以在容器完成后检查它的文件系统。

cdt-tests 的 Dockerfile 如下所示:

FROM node:6

RUN apt-get update && \
      apt-get -y install sudo

RUN sudo apt-get -y update
RUN sudo apt-get -y upgrade
RUN sudo apt-get install -y sqlite3 libsqlite3-dev

USER root

RUN mkdir -p /tmp/test-deps
RUN mkdir -p /usr/local/cdt-tests
WORKDIR /usr/local/cdt-tests

ENV SUMAN_POSTINSTALL_IS_DAEMON no

RUN rm -rf node_modules

RUN npm set progress=false
RUN npm config set loglevel=warn
RUN npm set loglevel=warn

COPY package.json .

RUN npm install --no-optional > /dev/null 2>&1
RUN npm install bower  > /dev/null 2>&1

COPY . .

RUN ./node_modules/.bin/bower install --config.interactive=false --allow-root  > /dev/null 2>&1

ENTRYPOINT ["/bin/bash", "/usr/local/cdt-tests/@run-tests.sh"]

我知道使用技巧来覆盖入口点并检查容器，如下所示:

docker run -it --entrypoint /bin/bash --name cdt-tests cdt-tests

但是，这对我当前的用例不起作用，因为我想在 @run-tests.sh 完成后 检查容器!

所以我有两个问题:

1. 如何在非守护进程容器完成运行后检查其文件系统？
2. 如何获取为非守护程序容器创建的容器的容器 ID(不使用 $(docker ps))。

如果我执行 docker ps -a，我会看到:

CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS                       PORTS               NAMES
08740a432d1c        cdt-tests           "/bin/bash /usr/lo..."   24 seconds ago      Exited (130) 7 seconds ago                       cdt-tests
f27a302b1d8f        cdt-server          "/bin/bash /usr/lo..."   38 seconds ago      Up 36 seconds                                    cdt-server
b854506e75df        cisco-selenium      "/opt/bin/entry_po..."   41 seconds ago      Up 39 seconds                4444/tcp            cdt-selenium
a37cab33b293        mongo               "docker-entrypoint..."   43 seconds ago      Up 41 seconds                27017/tcp           cdt-mongo

所以我们可以看到 cdt-tests 在那里，即使它不是守护进程。

所以我们尝试检查它，像这样:

docker exec cdt-tests /bin/bash

但是我们得到一个错误:

Error response from daemon: Container 08740a432d1c8f014bc138c82706de1e9682a052c088531d60b33c6acbbd5559 is not running

怎么办？

Answer 1

How can I inspect the filesystem of a non-daemon container after it has completed running?

使用 docker cp。查看docs

The docker cp utility copies the contents of SRC_PATH to the DEST_PATH. You can copy from the container’s file system to the local machine or the reverse, from the local filesystem to the container. (...) The CONTAINER can be a running or stopped container. The SRC_PATH or DEST_PATH can be a file or directory.

另一种选择是将容器具体化为新图像并在其上运行 bash:

docker commit <stopped-container> new_image_name
docker run -it --entrypoint /bin/bash new_image_name

---

How can I get the container id for the container that's created for a non-daemon container (without using $(docker ps)).

1) 当您执行 docker run -d 时，输出是已创建的容器 ID，因此您可以保存该信息:

container_id=$(docker run -d .......)

2) 这将向您显示已停止的测试容器:

docker ps -a --filter ancestor=cdt-tests

然后将最后停止的测试容器放入 var 中:

container_id=$(docker ps -q -a --filter ancestor=cdt-tests | head -n1)

每种情况都有许多其他变体。

---

编辑。使用卷版本方法，您可以将单个文件绑定(bind)为卷:

docker run -v ./tests.log:/path/to/logs/file.log -it --name cdt-tests cdt-tests