mirror of
https://github.com/kubernetes-sigs/prometheus-adapter.git
synced 2026-04-05 17:27:51 +00:00
94 lines
2.8 KiB
Go
94 lines
2.8 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 metrics
|
|
|
|
import (
|
|
"context"
|
|
"k8s.io/component-base/metrics/legacyregistry"
|
|
"net/http"
|
|
"net/url"
|
|
"time"
|
|
|
|
"github.com/prometheus/client_golang/prometheus"
|
|
|
|
apimetrics "k8s.io/apiserver/pkg/endpoints/metrics"
|
|
"k8s.io/component-base/metrics"
|
|
"sigs.k8s.io/prometheus-adapter/pkg/client"
|
|
)
|
|
|
|
var (
|
|
// queryLatency is the total latency of any query going through the
|
|
// various endpoints (query, range-query, series). It includes some deserialization
|
|
// overhead and HTTP overhead.
|
|
queryLatency = metrics.NewHistogramVec(
|
|
&metrics.HistogramOpts{
|
|
Namespace: "prometheus_adapter",
|
|
Subsystem: "prometheus_client",
|
|
Name: "request_duration_seconds",
|
|
Help: "Prometheus client query latency in seconds. Broken down by target prometheus endpoint and target server",
|
|
Buckets: prometheus.DefBuckets,
|
|
},
|
|
[]string{"endpoint", "server"},
|
|
)
|
|
)
|
|
|
|
func MetricsHandler() (http.HandlerFunc, error) {
|
|
registry := metrics.NewKubeRegistry()
|
|
err := registry.Register(queryLatency)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
apimetrics.Register()
|
|
return func(w http.ResponseWriter, req *http.Request) {
|
|
legacyregistry.Handler().ServeHTTP(w, req)
|
|
metrics.HandlerFor(registry, metrics.HandlerOpts{}).ServeHTTP(w, req)
|
|
}, nil
|
|
}
|
|
|
|
// instrumentedClient is a client.GenericAPIClient which instruments calls to Do,
|
|
// capturing request latency.
|
|
type instrumentedGenericClient struct {
|
|
serverName string
|
|
client client.GenericAPIClient
|
|
}
|
|
|
|
func (c *instrumentedGenericClient) Do(ctx context.Context, verb, endpoint string, query url.Values) (client.APIResponse, error) {
|
|
startTime := time.Now()
|
|
var err error
|
|
defer func() {
|
|
endTime := time.Now()
|
|
// skip calls where we don't make the actual request
|
|
if err != nil {
|
|
if _, wasAPIErr := err.(*client.Error); !wasAPIErr {
|
|
// TODO: measure API errors by code?
|
|
return
|
|
}
|
|
}
|
|
queryLatency.With(prometheus.Labels{"endpoint": endpoint, "server": c.serverName}).Observe(endTime.Sub(startTime).Seconds())
|
|
}()
|
|
|
|
var resp client.APIResponse
|
|
resp, err = c.client.Do(ctx, verb, endpoint, query)
|
|
return resp, err
|
|
}
|
|
|
|
func InstrumentGenericAPIClient(client client.GenericAPIClient, serverName string) client.GenericAPIClient {
|
|
return &instrumentedGenericClient{
|
|
serverName: serverName,
|
|
client: client,
|
|
}
|
|
}
|