actions-runner-controller/github/metrics/transport.go

69 lines
1.8 KiB
Go

// Package metrics provides monitoring of the GitHub related metrics.
//
// This depends on the metrics exporter of kubebuilder.
// See https://book.kubebuilder.io/reference/metrics.html for details.
package metrics
import (
"net/http"
"strconv"
"sync"
"github.com/prometheus/client_golang/prometheus"
"sigs.k8s.io/controller-runtime/pkg/metrics"
)
var onceRegister sync.Once
func Register() {
onceRegister.Do(func() {
metrics.Registry.MustRegister(metricRateLimit, metricRateLimitRemaining)
})
}
var (
// https://docs.github.com/en/rest/overview/resources-in-the-rest-api#rate-limiting
metricRateLimit = prometheus.NewGauge(
prometheus.GaugeOpts{
Name: "github_rate_limit",
Help: "The maximum number of requests you're permitted to make per hour",
},
)
metricRateLimitRemaining = prometheus.NewGauge(
prometheus.GaugeOpts{
Name: "github_rate_limit_remaining",
Help: "The number of requests remaining in the current rate limit window",
},
)
)
const (
// https://docs.github.com/en/rest/overview/resources-in-the-rest-api#rate-limiting
headerRateLimit = "X-RateLimit-Limit"
headerRateLimitRemaining = "X-RateLimit-Remaining"
)
// Transport wraps a transport with metrics monitoring
type Transport struct {
Transport http.RoundTripper
}
func (t Transport) RoundTrip(req *http.Request) (*http.Response, error) {
resp, err := t.Transport.RoundTrip(req)
if resp != nil {
parseResponse(resp)
}
return resp, err
}
func parseResponse(resp *http.Response) {
rateLimit, err := strconv.Atoi(resp.Header.Get(headerRateLimit))
if err == nil {
metricRateLimit.Set(float64(rateLimit))
}
rateLimitRemaining, err := strconv.Atoi(resp.Header.Get(headerRateLimitRemaining))
if err == nil {
metricRateLimitRemaining.Set(float64(rateLimitRemaining))
}
}