Add bind mount exclusion to prevent overwriting generated files with local files

[scirlig-ellation]

It's always annoying when I want to create a bind mount in order to synchronize local source code I'm editing, with code from docker container and all of the generated files.

Whether it's vendor directory or a binary file which eventually is used as an ENTRYPOINT or CMD they are getting removed when the bind mount is done. And since these files/directories are not available on local machine to avoid copying different binaries for different OS & ARCH inside linux container, docker removes them inside container as well when binding the source from local with the one from container

A solution to this might be to to do the bind mount first then use the snapshot fs which was created when the image was build, which will first bind mount the sources then allow the scripts which generate the binaries/directories to execute without being removed

Another solution would be to indicate in the volumes section some sort of exclude list when binding mount for the first time, somethings that would look like this:

volumes:
      - .:/usr/app:
          exclude:
            - fileA
            - fileB
            - dirA/

As a workaround to avoid this situation with volumes instead of running the generated binary in CMD or ENTRYPOINT we run some sort of shell script which generates again the binary and then executes the binary and now the CMD/ENTRYPOINT is referencing the shell script.
However would be a nice option with for initial bind mount some files which we choose would not be overwritten/removed in order to sync with local source code

docker-compose.yaml

version: "3.7"

services:
  redis:
    image: redis
    restart: always
    volumes:
      - redis-data:/data
    networks:
      - visits
    command: redis-server --appendonly yes
  visits-app:
    build: .
    restart: always
    ports:
      - "8080:8080"
    volumes:
      - ./:/usr/app
    networks:
      - visits
    

    # if this custom command is missing then we get an error that there is no node_modules
    # but in Dockerfile we indeed genereated node_modules by running npm install
    command: sh /usr/app/init.sh

networks:
  visits:

volumes:
  redis-data:

init.sh

npm install
npm start

Dockerfile

FROM node:alpine

ENV PORT 8080

EXPOSE $PORT

WORKDIR /usr/app

COPY ./package.json ./
RUN npm install
COPY . .

CMD npm start

Thank you for the awesome project and let me know if such a feature is a valid one and does not come against docker philosophy or if you need any help in implementing it