Can't build with beats-packer on Ubuntu 16.04: .../xgo: cannot download

Trying to build filebeat for arm. Using beats-packer w/docker. Make images and make pull-images both succeed. Make deps fails:

go get github.com/tsg/xgo
package github.com/tsg/xgo: cannot download, $GOPATH not set. For more details see: go help gopath
Makefile:49: recipe for target 'deps' failed
make: *** [deps] Error 1

Searched for this error came up empty.

It seems like your GOPATH is not setup properly. Best is to use go help gopath to get some more details on how to do this as recommended in the error.

Sorry for my ignorance, but isn't this building inside of docker instance? And so shouldn't the environment set the GOPATH?

Which beats-packer are you using? The one in the beats repo or the separate beats-packer repo?

From GitHub - here https://github.com/elastic/beats-packer

Ok, I see. That is probably the issue. We recently moved all packer stuff into the beats repo here: https://github.com/elastic/beats/tree/master/dev-tools/packer