mirror of
https://github.com/kubernetes-sigs/external-dns.git
synced 2025-11-04 04:31:00 +01:00
132 lines
3.3 KiB
Go
132 lines
3.3 KiB
Go
/*
|
|
Copyright 2017 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 controller
|
|
|
|
import (
|
|
"time"
|
|
|
|
"github.com/prometheus/client_golang/prometheus"
|
|
log "github.com/sirupsen/logrus"
|
|
|
|
"github.com/kubernetes-incubator/external-dns/plan"
|
|
"github.com/kubernetes-incubator/external-dns/registry"
|
|
"github.com/kubernetes-incubator/external-dns/source"
|
|
)
|
|
|
|
var (
|
|
registryErrors = prometheus.NewCounter(
|
|
prometheus.CounterOpts{
|
|
Name: "registry_errors_total",
|
|
Help: "Number of Registry errors.",
|
|
},
|
|
)
|
|
sourceErrors = prometheus.NewCounter(
|
|
prometheus.CounterOpts{
|
|
Name: "source_errors_total",
|
|
Help: "Number of Source errors.",
|
|
},
|
|
)
|
|
sourceEndpointsTotal = prometheus.NewGauge(
|
|
prometheus.GaugeOpts{
|
|
Namespace: "external_dns",
|
|
Subsystem: "source",
|
|
Name: "endpoints_total",
|
|
Help: "Number of Endpoints in all sources",
|
|
},
|
|
)
|
|
registryEndpointsTotal = prometheus.NewGauge(
|
|
prometheus.GaugeOpts{
|
|
Namespace: "external_dns",
|
|
Subsystem: "registry",
|
|
Name: "endpoints_total",
|
|
Help: "Number of Endpoints in the registry",
|
|
},
|
|
)
|
|
)
|
|
|
|
func init() {
|
|
prometheus.MustRegister(registryErrors)
|
|
prometheus.MustRegister(sourceErrors)
|
|
prometheus.MustRegister(sourceEndpointsTotal)
|
|
prometheus.MustRegister(registryEndpointsTotal)
|
|
}
|
|
|
|
// Controller is responsible for orchestrating the different components.
|
|
// It works in the following way:
|
|
// * Ask the DNS provider for current list of endpoints.
|
|
// * Ask the Source for the desired list of endpoints.
|
|
// * Take both lists and calculate a Plan to move current towards desired state.
|
|
// * Tell the DNS provider to apply the changes calucated by the Plan.
|
|
type Controller struct {
|
|
Source source.Source
|
|
Registry registry.Registry
|
|
// The policy that defines which changes to DNS records are allowed
|
|
Policy plan.Policy
|
|
// The interval between individual synchronizations
|
|
Interval time.Duration
|
|
}
|
|
|
|
// RunOnce runs a single iteration of a reconciliation loop.
|
|
func (c *Controller) RunOnce() error {
|
|
records, err := c.Registry.Records()
|
|
if err != nil {
|
|
registryErrors.Inc()
|
|
return err
|
|
}
|
|
registryEndpointsTotal.Set(float64(len(records)))
|
|
|
|
endpoints, err := c.Source.Endpoints()
|
|
if err != nil {
|
|
sourceErrors.Inc()
|
|
return err
|
|
}
|
|
sourceEndpointsTotal.Set(float64(len(endpoints)))
|
|
|
|
plan := &plan.Plan{
|
|
Policies: []plan.Policy{c.Policy},
|
|
Current: records,
|
|
Desired: endpoints,
|
|
}
|
|
|
|
plan = plan.Calculate()
|
|
|
|
err = c.Registry.ApplyChanges(plan.Changes)
|
|
if err != nil {
|
|
registryErrors.Inc()
|
|
return err
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Run runs RunOnce in a loop with a delay until stopChan receives a value.
|
|
func (c *Controller) Run(stopChan <-chan struct{}) {
|
|
ticker := time.NewTicker(c.Interval)
|
|
defer ticker.Stop()
|
|
for {
|
|
err := c.RunOnce()
|
|
if err != nil {
|
|
log.Error(err)
|
|
}
|
|
select {
|
|
case <-ticker.C:
|
|
case <-stopChan:
|
|
log.Info("Terminating main controller loop")
|
|
return
|
|
}
|
|
}
|
|
}
|