libpod make fails when GOPATH is not defined

[ssbarnea]

go language does not make GOPATH variable mandatory and states that it will default to ~/go when is not defined.

It seems that libpod Makefile is smart enough to detect if code was cloned in an unexpected location and to symlink it to ~/go/src/github.com/containers/libpod but the problem is that this does not make it work.

When this happens go fails to build its dependencies as it end-up looking for them relative to the "resolved" location of podman.

Still, runnning make without GOPATH fails because of this. here is the proof:

This is a serious issue because for non golang developers there are 9/10 changes that exactly this will happen: they will not have GOPATH defined and they will clone the code to another folder.

We need to find a way to make it work when this happens (without requiring any user intervension as this would be key for automating the installation).

$ make                                                                                                                                                                                                                                                               touch .gopathok
go build -i -ldflags '-L/usr/local/opt/zlib/lib -L/usr/local/opt/openssl/lib -L/usr/local/opt/nss/lib  -L/usr/local/opt/libarchive/lib -L/usr/local/opt/icu4c/lib -L/usr/local/opt/openssl/lib -L/usr/local/opt/sqlite/lib -X github.com/containers/libpod/libpod.gitCommit="23feb0d6f9a6a43e44f959c99100ae24d6c27f6d" -X github.com/containers/libpod/libpod.buildInfo=1542803025' -tags "seccomp btrfs_noversion exclude_graphdriver_btrfs containers_image_ostree_stub   varlink exclude_graphdriver_devicemapper" -o bin/podman github.com/containers/libpod/cmd/podman
can't load package: package github.com/containers/libpod/cmd/podman: cannot find package "github.com/containers/libpod/cmd/podman" in any of:
/usr/local/Cellar/go/1.11.2/libexec/src/github.com/containers/libpod/cmd/podman (from $GOROOT)
/Users/ssbarnea/go/src/github.com/containers/libpod/_output/src/github.com/containers/libpod/cmd/podman (from $GOPATH)
make: *** [podman] Error 1
FAIL: 2

Originally mentioned on #1840

[ghost]

Thanks for mentioning this.

I couldn't get the build to work for confusing reasons pertaining to varlink not being found (I'm not familiar with Go) and it turned out it was because I defined the GOPATH to be somewhere else than suggested by the installation README.

Now that I defined it exactly as in the README, the build works as intended.