Using Heroku cedar 14 stack as a Docker image

Question

Recently I had my application running on cedar-14 stack in Heroku But since End-of-life window has begun and builds won't be available, I decided to use Docker, so Heroku will host Docker container with my application on cedar-14 stack as base Docker image.

So far this is my Dockerfile

FROM heroku/cedar

WORKDIR /app

COPY index.js .
COPY package.json .

But when I was using plain cedar-14 on Heroku, I also had .buildpacks, Aptfile and Procfile and these files were interpreted by Heroku environment. How can I make them work in a Docker environment now?

Answer 1

.buildpacks, Aptfile is replaced by Dockerfile. You need to adjust your Dockerfile. Procfile is replaced by heroku.yml (see here.)

You can use cedar as your base image but I advise you to use latest LTS image and start from there.