File is not getting copied inside Docker container using cp command in a script-CodePudding

I am trying to run a custom-nginx server in Docker with a custom configuration file(Let's call it custom.configuration.conf)

And, I want the container to pick the configuration file based on the deployment environment. Hence in my repository, I have put the configuration as follows:

configuration(folder)
|
----> qa (sub-folder of configuration folder)
     |
     ----> custom.configuration.conf
|      
----> prd (sub-folder of configuration folder)
      |
      ---> custom.configuration.conf

To pick these files dynamically I introduced an environment variable DEPLOYMENT_ENVIRONMENT which I'm using in a file named start.sh

The start.sh script is as follows:

cp configuration/${DEPLOYMENT_ENVIRONMENT}/custom.configuration.conf /etc/nginx/conf.d
nginx -g "daemon off;"

My Dockerfile looks like this:

FROM nginx:1.23-alpine as application
WORKDIR /build
COPY configuration configuration
COPY start.sh start.sh
ENTRYPOINT /build/start.sh

The commands I'm using to build and run the container are:

docker build -t custom-nginx .

docker run -e DEPLOYMENT_ENVIRONMENT=qa -p 8080:80 custom-nginx

However, when I docker exec into the container I can't see the custom.configuration.conf at /etc/nginx/conf.d.

I'm running this on a Windows 10 machine with Docker Desktop.

start.sh, Dockerfile and configuration folder/files are at the root level in my repository.

I don't understand where I am going wrong. Please help me understand why am I not able to copy the file from container to container.

P.S: I actually tried running the cp configuration/${DEPLOYMENT_ENVIRONMENT}/custom.configuration.conf /etc/nginx/conf.d command inside the container to check if the command was wrong. However, it works if I do it manually inside the container, but fails when I run it using docker run.

CodePudding user response：

Add error handling to your entrypoint.sh script:

cp -v configuration/${DEPLOYMENT_ENVIRONMENT}/custom-configuration.conf /etc/nginx/conf.d
if [ "$?" != "0" ]
then
    echo "Could not copy configuration for DEPLOYMENT_ENVIRONMENT=${DEPLOYMENT_ENVIRONMENT}!"
    exit 1
fi
nginx -g "daemon off;"

Now check the docker logs when running the container. They should give you more hints of what happened.

CodePudding user response：

I've performed the EOL conversion from Windows(CR LF) to Unix(LF) as directed here: https://stackoverflow.com/a/50212715/6123155 and that fixed the issue for me.