Build portability improvements

[tgross]

After some offline discussions with @jen20 where he's trying to get ContainerPilot running on SmartOS, I want an issue to collect thoughts on things in our build/test infrastructure that aren't portable across OS's.

So far I've got:

• our Makefile is a GNU Make file, which isn't portable to BSD or Illumos/SmartOS. I know there are difference but I'm not really sure what they are.
• our integration tests run in Docker, which means they aren't portable to any platform that doesn't have Docker.
• we don't have a way of running automated tests in any environment except what TravisCI gives us, which I don't believe includes BSD or SmartOS (although I'd be happy to be wrong here).

[jen20]

The last two points I would add to this for discussion when we get round to looking at this are:

• our dependencies are not checked into this repository, meaning we have a build time dependency on glide (currently). This significantly increases cycle time, risks 'left-pad' style issues of missing dependencies due either to mistake/malice or GitHub being down, and prevents repeatable builds from easily being made without internet access from a simple clone of the project.
• our builds and unit tests run in Docker by default and need special casing to run on SmartOS (via the make local target.

[tgross]

our dependencies are not checked into this repository

I'm going to table this sub-topic as unrelated to this particular issue. Our plan has been to use whatever dep says we need to do once it's been deemed production-ready, so that we're not doing something out-of-the-ordinary from the rest of the golang community.

[jwreagor]

I started looking into the process changes to support building ContainerPilot under SmartOS given the existing build system and tooling. I took some notes...

• pkgin update && pkgin install go-1.8.3 git unzip gmake
• I had to comment out the glide install and build manually via go get github.com/Masterminds/glide && cd $GOPATH && make install
• The makefile needs to support go env values for GOPATH, GOOS, and GOARCH (I'll open a PR for this).
• glide still requires GOPATH in the environment.
• For whatever reason, make local build doesn't remove Docker commands from the rest of the process so I had to comment a few lines out for the build to work.
• All unit tests pass 💚

As a note, I'd be happy to continue down this path and upstream some of my changes if we had a SmartOS/ContainerPilot customer or community member that required it. Please leave a comment on this issue if you are such a user.

[tgross]

I had to comment out the glide install and build manually via go get github.com/Masterminds/glide && cd $GOPATH && make install glide still requires GOPATH in the environment.

We can probably do go install github.com/Masterminds/glide, given that we need the GOPATH anyways.

For whatever reason, make local build doesn't remove Docker commands from the rest of the process so I had to comment a few lines out for the build to work.

Yeah, the build target has the builder container as a prereq. Maybe a better approach would be to have the build/containerpilot_build just drop an empty file saying "hey no docker here" if there's no Docker available.

[tgross]

I do want to emphasize that although I don't use the Docker build much for day-to-day development, we've had more than one person tell us that having the whole development environment available inside Docker w/o requiring anything else has helped them make minor contributions that they might not have otherwise.

[jwreagor]

the whole development environment available inside Docker w/o requiring anything else has helped them make minor contributions that they might not have otherwise

I certainly concur with this statement and think Docker/Linux containers in development facilitate far easier public contributions. I'd like to continue this as an option for end users.