When using that
ARG option in your Dockerfile, you can specify the
--build-args option to define the value for the key that you specify in your Dockerfile to use for a environment variable as an example.
Today we will use the
env to set environment variables at build time.
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Building our Image, we will pass the value to our NAME argument:
Now when we run our container, we will notice that the build time argument has passed through to our environment variable from the running container:
When we build the image without specifying build arguments, and running the container:
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