Why do some of the repositories on docker hub not having dockerfile?

Question

When I use the repo on docker hub, I saw some of them have the corresponding docker files. Eg https://hub.docker.com/r/limesbonn/hisat2/dockerfile

But some of them don't. Eg: https://hub.docker.com/r/leanderd/single-cell-analysis

Could someone tell me why? Is there a way to get the dockerfile from a repo like this one: https://hub.docker.com/r/leanderd/single-cell-analysis ? Thanks in advance.

Answer 1

There is no Dockerfile information in image file. It's the instruction to build layers of images. Therefore, there is no way Docker Hub knows which Dockerfile is for the image. It needs to be shared by the authors of the image.

If the author uploads Dockerfile to docker hub, they can use the automatic creating image mechanism. So, that's why you can see Dockerfile there.