Guard against Canary being set to false at the same time as an
allocation is being stopped: this could cause RemoveTask to be called
with the wrong Canary value and leaking a service.
Deleting both Canary values is the safest route.
Also refactor Consul ServiceClient to take a struct instead of a massive
set of arguments. Meant updating a lot of code but it should be far
easier to extend in the future as you will only need to update a single
struct instead of every single call site.
Adds an e2e test for canary tags.
Adding this fields to the DriverContext object, will allow us to pass
them to the drivers.
An use case for this, will be to emit tagged metrics in the drivers,
which contain all relevant information:
- Job
- TaskGroup
- Task
- ...
Ref: https://github.com/hashicorp/nomad/pull/4185
Previously if only an interpolated variable used in a service or check
was changed we interpolated the old and new services and checks with the
new variable, so nothing appeared to have changed.
Fixes the panic mentioned in
https://github.com/hashicorp/nomad/issues/3420#issuecomment-341666932
While a leader task dying serially stops all follower tasks, the
synchronizing of state is asynchrnous. Nomad can shutdown before all
follower tasks have updated their state to dead thus saving the state
necessary to hit this panic: *have a non-terminal alloc with a dead
leader.*
The actual fix is a simple nil check to not assume non-terminal allocs
leader's have a TaskRunner.
@dadgar made the excellent observation in #3105 that TaskRunner removes
and re-registers checks on restarts. This means checkWatcher doesn't
need to do *any* internal restart tracking. Individual checks can just
remove themselves and be re-added when the task restarts.
This PR does the following:
* Adds a mechanism to emit events in the TaskRunner
* Vendors a new version of Consul-Template that allows extraction of
missing dependencies
* Adds logic to our consul_template.go to determine missing events and
emit them in a batched fashion.
* Refactors the consul_template code to split the run method and take in
a config struct rather than many parameters.
Fixes https://github.com/hashicorp/nomad/issues/2578
Ideally DriverNetwork would be fully populated in Driver.Prestart, but
Docker doesn't assign the container's IP until you start the container.
However, it's important to setup the port env vars before calling
Driver.Start, so Prestart should populate that.
