The e2e framework instantiates clients for Nomad/Consul but the
provisioning of the actual Nomad cluster is left to Terraform. The
Terraform provisioning process uses `remote-exec` to deploy specific
versions of Nomad so that we don't have to bake an AMI every time we
want to test a new version. But Terraform treats the resulting
instances as immutable, so we can't use the same tooling to update the
version of Nomad in-place. This is a prerequisite for upgrade testing.
This changeset extends the e2e framework to provide the option of
deploying Nomad (and, in the future, Consul/Vault) with specific
versions to running infrastructure. This initial implementation is
focused on deploying to a single cluster via `ssh` (because that's our
current need), but provides interfaces to hook the test run at the
start of the run, the start of each suite, or the start of a given
test case.
Terraform work includes:
* provides Terraform output that written to JSON used by the framework
to configure provisioning via `terraform output provisioning`.
* provides Terraform output that can be used by test operators to
configure their shell via `$(terraform output environment)`
* drops `remote-exec` provisioning steps from Terraform
* makes changes to the deployment scripts to ensure they can be run
multiple times w/ different versions against the same host.
Includes:
* baseline Windows AMI
* initial pass at Terraform configurations
* OpenSSH for Windows
Using OpenSSH is a lot nicer for Nomad developers than winrm would be,
plus it lets us avoid passing around the Windows password in the
clear.
Note that now we're copying up all the provisioning scripts and
configs as a zipped bundle because TF's file provisioner dies in the
middle of pushing up multiple files (whereas `scp -r` works fine).
We're also running all the provisioning scripts inside the userdata by
polling for the zip file to show up (gross!). This is because
`remote-exec` provisioners are failing on Windows with the same symptoms as:
https://github.com/hashicorp/terraform/issues/17728
If we can't fix this, it'll prevent us from having multiple Windows
clients running until TF supports count interpolation in the
`template_file`, which is planned for a later 0.12 release.
