如何通过Docker容器中的Dockerfile覆盖文件？

Question

I have to overwrite a file through Dockerfile. In particular on an Ubuntu container with Apache and PHP and I have to overwrite the file php5-cgi.conf. I tried to use the following command:

COPY php5-cgi.conf /etc/apache2/conf-enabled/php5-cgi.conf

but I had the error: File already exists

I have also tried to use the following command

RUN cp -f php5-cgi.conf /etc/apache2/conf-enabled/

but the file is not copied when the container is running, Is there any advice on this?

Answer 1

Drop the file name from the destination:

COPY php5-cgi.conf /etc/apache2/conf-enabled/

The destination is an absolute path (not filename), or a path relative to the work directory, into which the source will be copied inside the destination container.

Answer 2

I just tested following docker file with no problem.

from debian:jessie
COPY debian_version /etc/debian_version

As PolarisUser stated in comments, you need to put debian_version in the same folder as dockerfile or use absolute path . Another way would be mounting the file when running the container.

docker run -d -v php5-cgi.conf:/etc/apache2/conf-enabled/php5-cgi.conf --name your_container_name <imagename:tag> <startup command>

Answer 3

docker cp "yourfilename" "containername":/destination

以下是一个工作示例：

docker cp config.json bigdataapp:/app/src/bigdatapp/wwwroot/assets/config/config.json