This commit performs refactoring to pull out common service
registration objects into a new `client/serviceregistration`
package. This new package will form the base point for all
client specific service registration functionality.
The Consul specific implementation is not moved as it also
includes non-service registration implementations; this reduces
the blast radius of the changes as well.
There are bits of logic in callers of RemoveWorkload on group/task
cleanup hooks which call RemoveWorkload with the "Canary" version
of the workload, in case the alloc is marked as a Canary. This logic
triggers an extra sync with Consul, and also doesn't do the intended
behavior - for which no special casing is necessary anyway. When the
workload is marked for removal, all associated services and checks
will be removed regardless of the Canary status, because the service
and check IDs do not incorporate the canary-ness in the first place.
The only place where canary-ness matters is when updating a workload,
where we need to compute the hash of the services and checks to determine
whether they have been modified, the Canary flag of which is a part of
that.
Fixes#10842
This PR changes Nomad's wrapper around the Consul NamespaceAPI so that
it will detect if the Consul Namespaces feature is enabled before making
a request to the Namespaces API. Namespaces are not enabled in Consul OSS,
and require a suitable license to be used with Consul ENT.
Previously Nomad would check for a 404 status code when makeing a request
to the Namespaces API to "detect" if Consul OSS was being used. This does
not work for Consul ENT with Namespaces disabled, which returns a 500.
Now we avoid requesting the namespace API altogether if Consul is detected
to be the OSS sku, or if the Namespaces feature is not licensed. Since
Consul can be upgraded from OSS to ENT, or a new license applied, we cache
the value for 1 minute, refreshing on demand if expired.
Fixes https://github.com/hashicorp/nomad-enterprise/issues/575
Note that the ticket originally describes using attributes from https://github.com/hashicorp/nomad/issues/10688.
This turns out not to be possible due to a chicken-egg situation between
bootstrapping the agent and setting up the consul client. Also fun: the
Consul fingerprinter creates its own Consul client, because there is no
[currently] no way to pass the agent's client through the fingerprint factory.
This PR adds the common OSS changes for adding support for Consul Namespaces,
which is going to be a Nomad Enterprise feature. There is no new functionality
provided by this changeset and hopefully no new bugs.
Most allocation hooks don't need to know when a single task within the
allocation is restarted. The check watcher for group services triggers the
alloc runner to restart all tasks, but the alloc runner's `Restart` method
doesn't trigger any of the alloc hooks, including the group service hook. The
result is that after the first time a check triggers a restart, we'll never
restart the tasks of an allocation again.
This commit adds a `RunnerTaskRestartHook` interface so that alloc runner
hooks can act if a task within the alloc is restarted. The only implementation
is in the group service hook, which will force a re-registration of the
alloc's services and fix check restarts.
copy struct values
ensure groupserviceHook implements RunnerPreKillhook
run deregister first
test that shutdown times are delayed
move magic number into variable
* client: improve group service stanza interpolation and check_restart support
Interpolation can now be done on group service stanzas. Note that some task runtime specific information
that was previously available when the service was registered poststart of a task is no longer available.
The check_restart stanza for checks defined on group services will now properly restart the allocation upon
check failures if configured.
* connect: add unix socket to proxy grpc for envoy
Fixes#6124
Implement a L4 proxy from a unix socket inside a network namespace to
Consul's gRPC endpoint on the host. This allows Envoy to connect to
Consul's xDS configuration API.
* connect: pointer receiver on structs with mutexes
* connect: warn on all proxy errors
