Provide arm binaries

[cescoferraro]

I think it would be nice if we could provide arm binaries for the next release.
Gox does not support all arm arch, as of right now
It think you know that. I have used https://github.com/franciscocpg/gox lately and it works great.

We just need to change this dep

https://github.com/dnephin/dobi/blob/master/dockerfiles/Dockerfile.build#L16

But the build script need a little change

https://github.com/dnephin/dobi/blob/master/script/build#L7

Maybe

gox \
    -ldflags "-X github.com/dnephin/dobi/cmd.gitsha=$gitsha \
              -X \"github.com/dnephin/dobi/cmd.buildDate=$builddate\"" \
    -output="/go/bin/dobi-{{.OS}}/{{.Arch}}" \
    -arch="amd64 armv5 armv6 armv7" -os="$oslist"   \
    .

[dnephin]

I think providing arm binaries would be good.

Do you actually have a need for all of those versions? I'd rather not generate a bunch of binaries that no one is going to use. It will just add clutter to the releases page.

Maybe

-output="/go/bin/dobi-{{.OS}}-{{.Arch}}"
-osarch-list="..."

[cescoferraro]

@dnephin
I use dobi on the Raspberry PI. I would need at least armv6 and armv7.
Armv5 is for the earlier models· Would not $DOBI_BUILD_OS become useless with -osarch-list ?

[dnephin]

Ok, what does the current arm give you? just v7?

OSARCH is necessary because we don't want to build every 'os * arch' combination.

DOBI_BUILD_OS can change to accept an os/arch pair instead.

[cescoferraro]

current arm return just v7 @dnephin

[acwatkins]

I could use this as well. I managed to build on the latest by changing amd64 to arm64 on my amd64 machine. So, gox is working out of the current image just fine now.