Docker-node: Add qemu to this docker image

[dmednis]

What are your thoughts on adding qemu to this image?
It would be useful for e.g. for cross-building arm docker images on x86 machines using _multiarch/qemu-user-static:register_ .

[SimenB]

How does it help if we bundle QEMU? Seems like a niche requirement, and it's pretty easy to add yourself of you want it (I think? Never tried, to be honest)

[dmednis]

For crossbuilding to work it is required to have QEMU in the base image. It would be more convenient if one would not have to rebuild the node base image with QEMU each time a new update came out.
On the other hand not everyone need QEMU in their image. Wanted to find out other peoples take on this.

[chorrell]

👎 from me

As a general rule we try to avoid adding new packages to the images to keep the size down.

[yosifkit]

Just a note that you can run other architecture images using "Docker for Mac/Windows" which automatically uses qemu user mode emulation (nothing required to be installed in the container), but qemu often has problems:

• https://github.com/docker-library/official-images/pull/3206#issuecomment-324182757
• https://github.com/golang/go/issues/13024
• https://github.com/golang/go/issues/1508
• https://github.com/docker-library/tomcat/issues/69#issuecomment-303803574

[gibfahn]

For crossbuilding to work it is required to have QEMU in the base image. It would be more convenient if one would not have to rebuild the node base image with QEMU each time a new update came out.

Seems like the best solution would be for someone to create a new base image called node-qemu or whatever, and maybe try to get an automated travis build + push to Dockerhub whenever new node images come out.

[SimenB]

Closing as we will not be making this change.

If someone:tm: does what @gibfahn suggest above me, we can link to it from our readme, though.