Equivalent of --env-file for build-arg?

Question

I'm building a Docker image using multiple build args, and was wondering if it was possible to pass them to docker build as a file, in the same way --env-file can be pased to docker run. The env file will be parsed by docker run automatically and the variables made available in the container.

Is it possible to specify a file of build arguments in the same way?

Answer 1

There's no such an option, at least for now. But if you have too many build args and want to save it in a file, you can archive it as follows:

1. Save the following shell to buildargs.sh, make it executable and put it in your PATH:

   #!/bin/bash
   awk '{ sub ("\\\\$", " "); printf " --build-arg %s", $0  } END { print ""  }' $@
   

2. Build your image with argfile like:

   docker build $(buildargs.sh argfile) -t your_image .