Files
zeekay b61441f7d7 Volume: node-local persistent volumes, under our own name
A fork of Rancher's local-path-provisioner at v0.0.36. The behaviour is
unchanged and deliberately so — a directory on the node a pod lands on is
the right thing for a disk. What changes is identity.

The provisioner answers to hanzo.ai/volume rather than rancher.io/local-path.
That is not branding: two provisioners sharing one name race for the same
claims, and a stock k3s carries the upstream one, so a cluster running both
would settle our storage by chance. Data lives at /var/lib/hanzo/volume, so
reading a Hanzo cluster does not mean learning another vendor's directory.

Apache-2.0 as published, unaltered, with Rancher's attribution in NOTICE.

The README says what this is not: durability. A volume here dies with its
node. That is hanzoai/replicate's question, one layer up, and keeping the
two apart is what lets the disk stay this simple.
2026-09-07 17:30:01 -07:00

120 lines
2.9 KiB
Go

/*
Copyright 2018 The Kubernetes Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package leaderelection
import (
"sync"
)
// This file provides abstractions for setting the provider (e.g., prometheus)
// of metrics.
type leaderMetricsAdapter interface {
leaderOn(name string)
leaderOff(name string)
slowpathExercised(name string)
}
// LeaderMetric instruments metrics used in leader election.
type LeaderMetric interface {
On(name string)
Off(name string)
SlowpathExercised(name string)
}
type noopMetric struct{}
func (noopMetric) On(name string) {}
func (noopMetric) Off(name string) {}
func (noopMetric) SlowpathExercised(name string) {}
// defaultLeaderMetrics expects the caller to lock before setting any metrics.
type defaultLeaderMetrics struct {
// leader's value indicates if the current process is the owner of name lease
leader LeaderMetric
}
func (m *defaultLeaderMetrics) leaderOn(name string) {
if m == nil {
return
}
m.leader.On(name)
}
func (m *defaultLeaderMetrics) leaderOff(name string) {
if m == nil {
return
}
m.leader.Off(name)
}
func (m *defaultLeaderMetrics) slowpathExercised(name string) {
if m == nil {
return
}
m.leader.SlowpathExercised(name)
}
type noMetrics struct{}
func (noMetrics) leaderOn(name string) {}
func (noMetrics) leaderOff(name string) {}
func (noMetrics) slowpathExercised(name string) {}
// MetricsProvider generates various metrics used by the leader election.
type MetricsProvider interface {
NewLeaderMetric() LeaderMetric
}
type noopMetricsProvider struct{}
func (noopMetricsProvider) NewLeaderMetric() LeaderMetric {
return noopMetric{}
}
var globalMetricsFactory = leaderMetricsFactory{
metricsProvider: noopMetricsProvider{},
}
type leaderMetricsFactory struct {
metricsProvider MetricsProvider
onlyOnce sync.Once
}
func (f *leaderMetricsFactory) setProvider(mp MetricsProvider) {
f.onlyOnce.Do(func() {
f.metricsProvider = mp
})
}
func (f *leaderMetricsFactory) newLeaderMetrics() leaderMetricsAdapter {
mp := f.metricsProvider
if mp == (noopMetricsProvider{}) {
return noMetrics{}
}
return &defaultLeaderMetrics{
leader: mp.NewLeaderMetric(),
}
}
// SetProvider sets the metrics provider for all subsequently created work
// queues. Only the first call has an effect.
func SetProvider(metricsProvider MetricsProvider) {
globalMetricsFactory.setProvider(metricsProvider)
}