How to test my Dockerfile for my python project using GitHub actions?

• Sometimes we make errors in writing the docker file. If there is an error in the Dockerfile, the docker build will fail.

• Sometimes we may forget to specify dependencies in our Dockerfile. Let's take an example.

Suppose, I have a python script that can take the screenshot of any web page (whose URL is supplied).

• Now, in my code I am using pyppeeteer(Headless chrome/chromium automation library (unofficial port of puppeteer)
• pyppeeteer uses chromium and chrome driver. These are already installed in my machine. So, running pytest will pass in my local dev environment.
• I forget to specify the RUN commands in the dockerfile, that will install chromium and chrome driver. so running tests inside the container will fail. (although the docker build will succeed.)

I want to automate the task of building docker images and running tests in the container.

In the local machine, I can run docker build -t myproj . to build.

and for testing, I can run docker run -it myproj pytest (if i forget to add the RUN that installs chromium and chromedriver, then my pytest will fail inside container)

I hope I am able to explain my purpose.

Normally,in github actions,the python source code can be run on ubuntu, mac, windows etc. Besides the different os, I also want to build and test my dockerfile.

how can I do that? Please don't give tutorials to writing github actions. I am looking for an optimized way for achieving my task. My work can be done in many ways, but looking for specific instructions from an expert.