Adding support to dynamically discover metrics configs across all namespaces in the cluster

This commit is contained in:
Ramasai Venkatsitarambhaskar Tadepalli 2024-07-06 17:52:00 -04:00
parent 17cef511b1
commit 538dee837e
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GPG key ID: E34F5951CD929F15
3 changed files with 134 additions and 26 deletions

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@ -19,6 +19,7 @@ package main
import (
"crypto/tls"
"crypto/x509"
"errors"
"fmt"
"net/http"
"net/url"
@ -81,8 +82,12 @@ type PrometheusAdapter struct {
// MetricsMaxAge is the period to query available metrics for
MetricsMaxAge time.Duration
// DisableHTTP2 indicates that http2 should not be enabled.
DisableHTTP2 bool
metricsConfig *adaptercfg.MetricsDiscoveryConfig
DisableHTTP2 bool
// Load Dynamic Adapter Configurations
EnableMetricsConfigsDiscovery bool
// ConfigMap labels to select on
MetricsConfigsLabels string
metricsConfig *adaptercfg.MetricsDiscoveryConfig
}
func (cmd *PrometheusAdapter) makePromClient() (prom.Client, error) {
@ -157,6 +162,10 @@ func (cmd *PrometheusAdapter) addFlags() {
"period for which to query the set of available metrics from Prometheus")
cmd.Flags().BoolVar(&cmd.DisableHTTP2, "disable-http2", cmd.DisableHTTP2,
"Disable HTTP/2 support")
cmd.Flags().BoolVar(&cmd.EnableMetricsConfigsDiscovery, "enable-metrics-configs-disovery", cmd.EnableMetricsConfigsDiscovery,
"Load metrics configuration dynamically by querying the cluster for configmaps")
cmd.Flags().StringVar(&cmd.MetricsConfigsLabels, "metrics-configs-labels", cmd.MetricsConfigsLabels,
"Labels to query on while filtering ConfigMap objects when dynamically discovering metrics configuration")
// Add logging flags
logs.AddFlags(cmd.Flags())
@ -165,7 +174,16 @@ func (cmd *PrometheusAdapter) addFlags() {
func (cmd *PrometheusAdapter) loadConfig() error {
// load metrics discovery configuration
if cmd.AdapterConfigFile == "" {
return fmt.Errorf("no metrics discovery configuration file specified (make sure to use --config)")
if !cmd.EnableMetricsConfigsDiscovery {
return fmt.Errorf("loading dynamic config is turned off, and no metrics discovery configuration file specified (make sure to use --config)")
}
// Assign empty metrics config to prevent nilptr exceptions
cmd.metricsConfig = &adaptercfg.MetricsDiscoveryConfig{
Rules: []adaptercfg.DiscoveryRule{},
ExternalRules: []adaptercfg.DiscoveryRule{},
ResourceRules: &adaptercfg.ResourceRules{},
}
return nil
}
metricsConfig, err := adaptercfg.FromFile(cmd.AdapterConfigFile)
if err != nil {
@ -178,7 +196,7 @@ func (cmd *PrometheusAdapter) loadConfig() error {
}
func (cmd *PrometheusAdapter) makeProvider(promClient prom.Client, stopCh <-chan struct{}) (provider.CustomMetricsProvider, error) {
if len(cmd.metricsConfig.Rules) == 0 {
if len(cmd.metricsConfig.Rules) == 0 && !cmd.EnableMetricsConfigsDiscovery {
return nil, nil
}
@ -203,7 +221,7 @@ func (cmd *PrometheusAdapter) makeProvider(promClient prom.Client, stopCh <-chan
}
// construct the provider and start it
cmProvider, runner := cmprov.NewPrometheusProvider(mapper, dynClient, promClient, namers, cmd.MetricsRelistInterval, cmd.MetricsMaxAge)
cmProvider, runner := cmprov.NewPrometheusProvider(mapper, dynClient, promClient, namers, cmd.MetricsRelistInterval, cmd.MetricsMaxAge, cmd.EnableMetricsConfigsDiscovery, cmd.MetricsConfigsLabels)
runner.RunUntil(stopCh)
return cmProvider, nil
@ -340,6 +358,11 @@ func main() {
klog.Fatalf("unable to load metrics discovery config: %v", err)
}
// verify the dynamic metrics loading properties
if cmd.EnableMetricsConfigsDiscovery && cmd.MetricsConfigsLabels == "" {
klog.Fatal("", errors.New("Did not specify --metrics-configs-labels to provide a list of labels to select on but metrics configs discovery is turned on"))
}
// stop channel closed on SIGTERM and SIGINT
stopCh := genericapiserver.SetupSignalHandler()