create entry-point script to get all env variables starting with VUE_APP_ and take it's value

I would like to Dockerize my existing vuejs app for staging , production and I used multi staged approach to create my app container and I'm using Ubuntu 18.04 and this is my,

Dockerfile

# build stageFROM node:lts-alpine as build-stageLABEL maintainer="servers@xpl.com"WORKDIR /appCOPY package*.json ./RUN npm installCOPY . ./RUN npm run build# production stageFROM nginx:stable-alpineLABEL maintainer="servers@xpl.com"COPY --from=build-stage /app/dist/ /app/dist/COPY nginx/nginx.conf /etc/nginx/EXPOSE 80

I don't want to create docker-compose.yml file to assign anything and my question would be like , Create .env file with hardcoded values.

i.e

VUE_APP_API_ENDPOINT_DOMAIN=VUE_APP_API_ENDPOINT_DOMAIN

1 .When running npm run build it'll put VUE_APP_API_ENDPOINT_DOMAIN in the dest files.

2 .We need to know which file. Probably index.html I believe.

3 .We create entry-point.sh script will get all env variables starting with VUE_APP_ and take it's value. And then using sed command we find and replace those hard coded variable placeholders in index.html.And finally start Nginx.

I was stuck on step 3.