Dockerignore troubles


I commonly used to create a .Dockerignore file next to my Dockerfile. After countless hours of ignoring the problems in my setup, I found out that the uppercase .Dockerignore doesn't get picked up by Docker on MacOS. Only the lowercase .dockerignore is valid.

I didn't find official documentation on this, but I think it's because both MacOS and Linux are case-sensitive, while Windows isn't. I don't remember why I got used to the .Dockerignore convention, but I swear I saw someone using it in the wild. Or it's my (un)logical reasoning that, because Dockerfile is uppercased, .Dockerignore should be uppercased as well.

Either way, stay away from .Dockerfiles and stick to .dockerfiles.

This is post 050 of #100DaysToOffload.

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