prometheus-adapter/pkg/custom-provider/external_provider.go
Tony Compton d1827c5611 Tons of movement. See notes.
* Renamed `MetricNamer` to `SeriesConverter` and renamed `MetricNameConverter` to `MetricNamer`.
* Simplified the `metricConverter` code.
* Greatly simplified the `externalSeriesRegistry` and removed the `externalInfoMap` code.
* Fixed doc comment format.
* Still several `TODO`s to address.
2018-08-29 14:30:26 -04:00

74 lines
2.3 KiB
Go

package provider
import (
"context"
"fmt"
"k8s.io/apimachinery/pkg/runtime/schema"
"github.com/golang/glog"
pmodel "github.com/prometheus/common/model"
"github.com/kubernetes-incubator/custom-metrics-apiserver/pkg/provider"
apierr "k8s.io/apimachinery/pkg/api/errors"
"k8s.io/apimachinery/pkg/labels"
"k8s.io/metrics/pkg/apis/external_metrics"
prom "github.com/directxman12/k8s-prometheus-adapter/pkg/client"
)
// TODO: Make sure everything has the proper licensing disclosure at the top.
type externalPrometheusProvider struct {
promClient prom.Client
metricConverter MetricConverter
seriesRegistry ExternalSeriesRegistry
}
// NewExternalPrometheusProvider creates an ExternalMetricsProvider capable of responding to Kubernetes requests for external metric data.
func NewExternalPrometheusProvider(seriesRegistry ExternalSeriesRegistry, promClient prom.Client, converter MetricConverter) provider.ExternalMetricsProvider {
return &externalPrometheusProvider{
promClient: promClient,
seriesRegistry: seriesRegistry,
metricConverter: converter,
}
}
func (p *externalPrometheusProvider) GetExternalMetric(namespace string, metricName string, metricSelector labels.Selector) (*external_metrics.ExternalMetricValueList, error) {
selector, found, err := p.seriesRegistry.QueryForMetric(namespace, metricName, metricSelector)
if err != nil {
glog.Errorf("unable to generate a query for the metric: %v", err)
return nil, apierr.NewInternalError(fmt.Errorf("unable to fetch metrics"))
}
if !found {
return nil, provider.NewMetricNotFoundError(p.selectGroupResource(namespace), metricName)
}
queryResults, err := p.promClient.Query(context.TODO(), pmodel.Now(), selector)
if err != nil {
glog.Errorf("unable to fetch metrics from prometheus: %v", err)
// don't leak implementation details to the user
return nil, apierr.NewInternalError(fmt.Errorf("unable to fetch metrics"))
}
return p.metricConverter.Convert(queryResults)
}
func (p *externalPrometheusProvider) ListAllExternalMetrics() []provider.ExternalMetricInfo {
return p.seriesRegistry.ListAllMetrics()
}
func (p *externalPrometheusProvider) selectGroupResource(namespace string) schema.GroupResource {
if namespace == "" {
return nsGroupResource
}
return schema.GroupResource{
Group: "",
Resource: "",
}
}