Does FROM instruction support variables within a Dockerfile?
Experience Level: Senior
Tags: Docker
Answer
Yes. You can use the ARG instruction. The ARG instruction defines a variable that users can pass at build-time to the builder with the docker build command using the --build-arg <varname>=<value> flag. If a user specifies a build argument that was not defined in the Dockerfile, the build outputs a warning.
ARG CODE_VERSION=latest
FROM base:${CODE_VERSION}
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