This changeset moves the installation of Nomad binaries out of the
provisioning framework and into scripts that are installed on the remote host
during AMI builds.
This provides a few advantages:
* The provisioning framework can be reduced in scope (with the goal of moving
most of it into the Terraform stack entirely).
* The scripts can be arbitrarily complex if we don't have to stuff them into
ssh commands, so it's easier to make them idempotent. In this changeset, the
scripts check the version of the existing binary and don't re-download when
using the `--nomad_sha` or `--nomad_version` flags.
* The scripts can be OS/distro specific, which helps in building new test
targets.
This extracts some common API-idiosyncracy-handling patterns from model serialisers into properties that are processed by the application serialiser:
* arrayNullOverrides converts a null property value to an empty array
* mapToArray converts a map to an array of maps, using the original map keys as Name properties on the array maps
* separateNanos splits nanosecond-containing timestamps into millisecond timestamps and separate nanosecond properties
Just a smattering of attempted improvements as I read through this
again. Some of my goals:
- Tried to add more high level info to the intro to set the context
- Clarify the difference between *test* dev and *agent* dev workflows
- Add -timeout to provisioning step because cable Internet is lol
If a core job fails more than the delivery limit, the leader will create a new
eval with the TriggeredBy field set to `failed-follow-up`.
Evaluations for core jobs have the leader's ACL, which is not valid on another
leader after an election. The `failed-follow-up` evals do not have ACLs, so
core job evals that fail more than the delivery limit or core job evals that
span leader elections will never succeed and will be re-enqueued forever. So
we should not retry with a `failed-follow-up`.
The `regionForJob` function in the HTTP job endpoint overrides the region for
multiregion jobs to `global`, which is used as a sentinel value in the
server's job endpoint to avoid re-registration loops. This changeset removes
an extraneous check that results in errors in the web UI and makes
round-tripping through the HTTP API cumbersome for all consumers.
