Add build option "--hostname" for buildx to be able to customize hostname during build image

[ShemTovYosef]

Hi,

As part of this task: moby/buildkit#1301 buildkit now supports for customizing hostname like this:
buildctl build --frontend=dockerfile.v0 --local dockerfile=. --local context=. --opt hostname=testtest

I want to ask to add this ability to buildx itself to be able to use it like:
docker build --hostname=testtest -t host .

Thanks,
Yosef

[tonistiigi]

I guess we can start by adding a build-arg with BUILDKIT_ prefix like we do for some other options.

[ShemTovYosef]

Hi @tonistiigi

At this moment can we call buildx by specifying buildkit options, i.e., if I want to call "--opt hostname=testtest" of buildctl by buildx, is any way to do it?

Like this one but it's not working by using ---config as described in documentation: https://github.com/moby/buildkit/blob/master/docs/buildkitd.toml.md
docker buildx create --use --name builder-with-opts --config hostname=testtest
but I don't know how to specify hostname in it, this field is not described in buildkitd.toml documentation

[tonistiigi]

we shouldn't set it per builder, but per build. eg. docker buildx build --build-arg BUILDKIT_SANDBOX_HOSTNAME= .

[ShemTovYosef]

ping if someone interested to implement it

[ShemTovYosef]

Any updates on this issue?

[ShemTovYosef]

Or any workaround how to pass buildkit options from buildx?

[li-zhixin]

Any updates on this issue?

[ShemTovYosef]

HI @jingxiaolu
Maybe you will have a time to help with it and finish the final step?

[totszwai]

So how do we set hostname with this?

[ShemTovYosef]

Just to use build arg moby/buildkit#2373