build arm64 images

[ludfjig]

We should be building arm64 images, not only amd64. It is also requested by mcr

[troy0820]

Couple of other issues are linked to this one sort of.

#2397
#1497
#1856

I think the problem is related to some of these with the bugs that were reported. However, these issues are old and we may not face the same problems. Worth investigating.

[sbshah97]

Hi can someone help on how to approach this and go about this? I am a new contributor here

[robinbraemer]

Porter's mission is to be a widely accessible cloud-native apps CLI, yet it doesn't support arm, that is widely used nowadays server- and clientside. This issue deserves more attention from core maintainers as it is directly correlated to the success of adopting Porter and CNAB.

From what I see, to make progress would be to add arm to these locations(?):

• porter/magefile.go

  Line 354 in 39d28db

  err := shx.Command("docker", "build", "-t", img, "-f", "build/images/client/Dockerfile", ".").

• porter/magefile.go

  Line 367 in 39d28db

  err = shx.Command("docker", "build", "-t", img, "--build-arg", "PORTER_VERSION="+info.Version, "--build-arg", "REGISTRY="+registry, "-f", "build/images/agent/Dockerfile", ".").

• all hard-coded mentions of architecture https://github.com/getporter/porter/tree/main/build/images

Go builds should use as already defaulted as ARGS by Docker BuildKit:

GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} go build

Docker builds should add a platforms flag:

docker build --platform linux/amd64,linux/arm64 .