Getting a docker build ready for (Heroku) deployment?

I've got a local application working using docker-compose up, this gets me the servers I need and they function just fine locally.

Now I've tried getting a build.sh started, but I can't figure out how to build a docker image using either docker-compose or just regular docker-cli with the final result of the build process. (The /dist/ folder).

Could somebody explain to me how a regular process like this would look like, and what steps a build process would walk through in docker terms?
Would I need a seperate command to package it for deployment? Is there a separate configuration required?

For building docker image using docker-compose you can add build: field to the service you want to build and assign to it the path of the Dockerfile for example:

version: '2'
services:
  web:
    build: .
    ports:
     - "8080:80"
    volumes:
     - /project:/var/www/html

This example define a web service which:

• Uses an image that’s built from the Dockerfile in the current directory.

• Forwards the exposed port 80 on the container to port 8080 on the

host machine

• Mounts the project directory on the host to /project inside the

container, allowing you to modify the code without having to rebuild
the image.

To build the image, simply issue the build command via docker-compose, as such: docker-compose build.

StackExchange DevOps Q#1637, answer score: 1