TODO: Upgrade Alpine base

[rvagg]

This is a TODO for someone who wants to change the recipe Dockerfiles to make them work with newer Alpine, and test that they can still build Node.js properly. fetch-source, musl and headers all use FROM alpine:3.9. To test an upgrade, you'd need to switch the FROM, build images, then run containers in a way that executes their build tasks. It might be a little involved to make it work locally but hopefully by looking at the recipes it's not too unclear what needs to be done (fetch-source is a special case recipe that's run before all the rest that simply downloads and unpacks the tarball).

I think it would be safe to upgrade to 3.12, they're based on musl 1.1.x (see). while 3.13 jumps to 1.2.x(see).

We don't have a strict contract here for libc versions or any minimum level of support across major versions. We also don't currently have a mechanism to switch recipes based on Node.js major versions. So I think for now we could just do 3.12, cross our fingers a little and hope that we still produce maximally compatible binaries. Then we can make the 1.2.x jump a bit later when the ecosystem has moved on a little. The musl ecosystem is largely made up of Alpine (tho there are more), and Alpine users tend to be on much quicker upgrade cycles so give it 6-12 months and we could probably make a decent bet that folks have moved on and then we can switch to a newer Alpine with 1.2.x.

/cc @nodejs/docker

[LaurentGoderre]

Would be ok to produce both versions until we know that the new one works?

[rvagg]

how would we name them? how would we get people to consume and test the new ones?

[LaurentGoderre]

We could use the new one in the docker image. It would be a lot less risky to upgrade if we have the other version to rollback to if there's a problem

[mckaygerhard]

i thinks using a newer base apine is pointless cos thi project try to compile for unsupported targets, alpine already have a official package for nodejs,

so in fact is right choose using an older alpine docker base for buils so will sure the backguard compatibility with all older or midlle-recent alpine unsupported targets