No such file or directory in docker build

Question

I am new to docker and attempting to port an app over to it. Essentially, on startup, the app needs to perform some environment dependent work which I have encapsulated in a script.

My app looks like

Dockerfile
scripts/run.sh
build-development/stuff
build-production/stuff

Here is my Dockerfile:

FROM nginx
RUN chmod +x scripts/run.sh
CMD ["scripts/run.sh", APP_ENV]
EXPOSE 80

and here is scripts/run.sh:

#!/bin/bash

mkdir dist

chmod -R 777 dist

if [ $1 == "development" ]
then
    cp -R build-development/. /usr/share/nginx/html
fi

if [ $1 == "stage" ]
then
    cp -R build-production/. /usr/share/nginx/html
    sed -i 's/production/stage/g' dist/index.html
fi

if [ $1 == "production" ]
then
    cp -R build-production/. /usr/share/nginx/html
fi

The idea is that I will run the image like:

docker run -e APP_ENV=development app-name

and it will be fed into the script, which will copy the correct files.

Unfortunately, I never get to run the image because during the build step:

docker build -t app-name .

I get errors about

scripts/run.sh not being a file or directory

I don't understand why I am getting this error, I guess it is from naive misunderstanding on my part. What am I doing wrong and how can I make my project work?

Thanks in advance.

Answer 1

It seems like you want scripts/run.sh to be a part of the container. In that case, before you try to run the chmod you need to copy it into the image.

FROM nginx
COPY scripts/run.sh /scripts/run.sh
RUN chmod +x /scripts/run.sh
CMD ["/scripts/run.sh", APP_ENV]

This will copy ./scripts/run.sh (relative to your build directory) into the image at /scripts/run.sh, so your later RUN and CMD have that path available.