在 docker 容器中安装依赖项后如何复制回主机 package-lock.json/yarn.lock？

Question

I'm using Docker containers to run my CRA application. I use 2 different DockerFile, one for running CRA in development and one to generate the build. During the step of installing dependencies:

FROM node:15.5.0-alpine3.10

USER node

RUN mkdir /home/node/code
WORKDIR /home/node/code

COPY package.json yarn.lock ./
RUN yarn

ENV PATH /home/node/code/node_modules/.bin:$PATH

CMD yarn start

I need to copy my updated yarn.lock file (or package-lock.json file is using NPM) back to host after the container generate the new version of the file.

I had search the solution everywhere, but I didn't find anything to resolve this problem.

Answer 1

I'm using Docker containers to run my CRA application. I use 2 different DockerFile, one for running CRA in development and one to generate the build. During the step of installing dependencies:

FROM node:15.5.0-alpine3.10

USER node

RUN mkdir /home/node/code
WORKDIR /home/node/code

COPY package.json yarn.lock ./
RUN yarn

ENV PATH /home/node/code/node_modules/.bin:$PATH

CMD yarn start

I need to copy my updated yarn.lock file (or package-lock.json file is using NPM) back to host after the container generate the new version of the file.

I had search the solution everywhere, but I didn't find anything to resolve this problem.

Answer 2

I stumbled my way here, a possible solution is to use:

RUN yarn install --frozen-lockfile

Answer 3

Didn't find any way to copy back the package-lock.json / yarn.lock file after install dependencies inside docker container.

But I solved it moving it into a folder and syncing it using a volume (examples include only relevant code for this case).

File ./Dockerfile :

FROM node:12-alpine

# Copy all files inside sync-package-lock into workdir of docker 
COPY sync-package-lock ./

# If package-lock.json is not found in previous step, it will be created in the following npm install
RUN npm install
RUN npm run build

# Following entrypoint will copy the package-lock.json to the sync volume
COPY docker-entrypoint.sh /docker-entrypoint.sh
RUN chmod +x /docker-entrypoint.sh

ENTRYPOINT [ "/docker-entrypoint.sh" ]
CMD [ "npm", "run", "serve" ]

File ./docker-entrypoint.sh :

#!/bin/sh

# copy package-lock.json to the shared volume "sync-package-lock" so its synced between host and container
cp -a /app/package-lock.json /app/sync-package-lock/

echo "Finised docker-entrypoint.sh"

# Finish entrypoint. Run the CMD
exec "$@"

File docker-compose.yml :

    volumes:
        - "../backend/sync-package-lock:/app/sync-package-lock"