Be Careful with Using ARG in Dockerfile - A Subtle Trap

This article discusses the use of arguments in a Dockerfile, which is a key aspect of building container images. The author highlights some nuances that may surprise users, especially those who are new to working with Docker. Using the ARG command in a Dockerfile allows for defining variables that can be utilized during the image build process. However, it is crucial to understand that these arguments may not be available in the final image, which can lead to unforeseen issues. The author provides practical examples that illustrate how improper use of ARG can affect the functioning of applications running within a container. Finally, the advice on managing arguments in Docker is extremely valuable, helping users avoid the traps that often catch them off guard.