feat(inputs.prometheus): Control which pod metadata is added as tags (#12851)

models/filter.go

@@ -161,14 +161,7 @@ func (f *Filter) shouldNamePass(key string) bool {
 // shouldFieldPass returns true if the metric should pass, false if it should drop
 // based on the drop/pass filter parameters
 func (f *Filter) shouldFieldPass(key string) bool {
-	if f.fieldPassFilter != nil && f.fieldDropFilter != nil {
-		return f.fieldPassFilter.Match(key) && !f.fieldDropFilter.Match(key)
-	} else if f.fieldPassFilter != nil {
-		return f.fieldPassFilter.Match(key)
-	} else if f.fieldDropFilter != nil {
-		return !f.fieldDropFilter.Match(key)
-	}
-	return true
+	return ShouldPassFilters(f.fieldPassFilter, f.fieldDropFilter, key)
 }
 
 // shouldTagsPass returns true if the metric should pass, false if it should drop
@@ -217,6 +210,17 @@ func (f *Filter) filterTags(metric telegraf.Metric) {
 	}
 }
 
+func ShouldPassFilters(include filter.Filter, exclude filter.Filter, key string) bool {
+	if include != nil && exclude != nil {
+		return include.Match(key) && !exclude.Match(key)
+	} else if include != nil {
+		return include.Match(key)
+	} else if exclude != nil {
+		return !exclude.Match(key)
+	}
+	return true
+}
+
 func ShouldTagsPass(passFilters []TagFilter, dropFilters []TagFilter, tags []*telegraf.Tag) bool {
 	pass := func(tpf []TagFilter) bool {
 		for _, pat := range tpf {

plugins/inputs/prometheus/README.md

@@ -95,6 +95,13 @@ See the [CONFIGURATION.md][CONFIGURATION.md] for more details.
   # eg. To scrape pods on a specific node
   # kubernetes_field_selector = "spec.nodeName=$HOSTNAME"
 
+  ## Filter which pod annotations and labels will be added to metric tags
+  #
+  # pod_annotation_include = ["annotation-key-1"]
+  # pod_annotation_exclude = ["exclude-me"]
+  # pod_label_include = ["label-key-1"]
+  # pod_label_exclude = ["exclude-me"]
+
   # cache refresh interval to set the interval for re-sync of pods list.
   # Default is 60 minutes.
   # cache_refresh_interval = 60

plugins/inputs/prometheus/kubernetes.go

@@ -5,8 +5,6 @@ import (
 	"crypto/tls"
 	"encoding/json"
 	"fmt"
-	"github.com/influxdata/telegraf"
-	"github.com/influxdata/telegraf/models"
 	"net"
 	"net/http"
 	"net/url"
@@ -15,6 +13,9 @@ import (
 	"strconv"
 	"time"
 
+	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/models"
+
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/fields"
 	"k8s.io/apimachinery/pkg/labels"
@@ -369,10 +370,13 @@ func registerPod(pod *corev1.Pod, p *Prometheus) {
 	}
 
 	p.Log.Debugf("will scrape metrics from %q", targetURL.String())
-	// add annotation as metrics tags
-	tags := pod.Annotations
-	if tags == nil {
-		tags = map[string]string{}
+	tags := map[string]string{}
+
+	// add annotation as metrics tags, subject to include/exclude filters
+	for k, v := range pod.Annotations {
+		if models.ShouldPassFilters(p.podAnnotationIncludeFilter, p.podAnnotationExcludeFilter, k) {
+			tags[k] = v
+		}
 	}
 
 	tags["pod_name"] = pod.Name
@@ -382,9 +386,11 @@ func registerPod(pod *corev1.Pod, p *Prometheus) {
 	}
 	tags[podNamespace] = pod.Namespace
 
-	// add labels as metrics tags
+	// add labels as metrics tags, subject to include/exclude filters
 	for k, v := range pod.Labels {
-		tags[k] = v
+		if models.ShouldPassFilters(p.podLabelIncludeFilter, p.podLabelExcludeFilter, k) {
+			tags[k] = v
+		}
 	}
 	podURL := p.AddressToURL(targetURL, targetURL.Hostname())
 

plugins/inputs/prometheus/kubernetes_test.go

@@ -1,9 +1,10 @@
 package prometheus
 
 import (
-	"k8s.io/client-go/tools/cache"
 	"testing"
 
+	"k8s.io/client-go/tools/cache"
+
 	"github.com/stretchr/testify/require"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -264,6 +265,96 @@ func TestInvalidFieldSelector(t *testing.T) {
 	require.NotEqual(t, err, nil)
 }
 
+func TestAnnotationFilters(t *testing.T) {
+	p := pod()
+	p.Annotations = map[string]string{
+		"prometheus.io/scrape": "true",
+		"includeme":            "true",
+		"excludeme":            "true",
+		"neutral":              "true",
+	}
+
+	cases := []struct {
+		desc         string
+		include      []string
+		exclude      []string
+		expectedTags []string
+	}{
+		{"Just include",
+			[]string{"includeme"},
+			nil,
+			[]string{"includeme"}},
+		{"Just exclude",
+			nil,
+			[]string{"excludeme"},
+			[]string{"includeme", "neutral"}},
+		{"Include & exclude",
+			[]string{"includeme"},
+			[]string{"exludeme"},
+			[]string{"includeme"}},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.desc, func(t *testing.T) {
+			prom := &Prometheus{Log: testutil.Logger{}}
+			prom.PodAnnotationInclude = tc.include
+			prom.PodAnnotationExclude = tc.exclude
+			require.NoError(t, prom.initFilters())
+			registerPod(p, prom)
+			for _, pd := range prom.kubernetesPods {
+				for _, tagKey := range tc.expectedTags {
+					require.Contains(t, pd.Tags, tagKey)
+				}
+			}
+		})
+	}
+}
+
+func TestLabelFilters(t *testing.T) {
+	p := pod()
+	p.Annotations = map[string]string{"prometheus.io/scrape": "true"}
+	p.Labels = map[string]string{
+		"includeme": "true",
+		"excludeme": "true",
+		"neutral":   "true",
+	}
+
+	cases := []struct {
+		desc         string
+		include      []string
+		exclude      []string
+		expectedTags []string
+	}{
+		{"Just include",
+			[]string{"includeme"},
+			nil,
+			[]string{"includeme"}},
+		{"Just exclude",
+			nil,
+			[]string{"excludeme"},
+			[]string{"includeme", "neutral"}},
+		{"Include & exclude",
+			[]string{"includeme"},
+			[]string{"exludeme"},
+			[]string{"includeme"}},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.desc, func(t *testing.T) {
+			prom := &Prometheus{Log: testutil.Logger{}}
+			prom.PodLabelInclude = tc.include
+			prom.PodLabelExclude = tc.exclude
+			require.NoError(t, prom.initFilters())
+			registerPod(p, prom)
+			for _, pd := range prom.kubernetesPods {
+				for _, tagKey := range tc.expectedTags {
+					require.Contains(t, pd.Tags, tagKey)
+				}
+			}
+		})
+	}
+}
+
 func pod() *corev1.Pod {
 	p := &corev1.Pod{ObjectMeta: metav1.ObjectMeta{}, Status: corev1.PodStatus{}, Spec: corev1.PodSpec{}}
 	p.Status.PodIP = "127.0.0.1"

plugins/inputs/prometheus/prometheus.go

@@ -15,6 +15,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/influxdata/telegraf/filter"
 	"github.com/influxdata/telegraf/models"
 	"k8s.io/client-go/tools/cache"
 
@@ -119,6 +120,17 @@ type Prometheus struct {
 	NamespaceAnnotationPass map[string][]string `toml:"namespace_annotation_pass"`
 	NamespaceAnnotationDrop map[string][]string `toml:"namespace_annotation_drop"`
 
+	PodAnnotationInclude []string `toml:"pod_annotation_include"`
+	PodAnnotationExclude []string `toml:"pod_annotation_exclude"`
+
+	PodLabelInclude []string `toml:"pod_label_include"`
+	PodLabelExclude []string `toml:"pod_label_exclude"`
+
+	podAnnotationIncludeFilter filter.Filter
+	podAnnotationExcludeFilter filter.Filter
+	podLabelIncludeFilter      filter.Filter
+	podLabelExcludeFilter      filter.Filter
+
 	// Only for monitor_kubernetes_pods=true
 	CacheRefreshInterval int `toml:"cache_refresh_interval"`
 
@@ -193,6 +205,10 @@ func (p *Prometheus) Init() error {
 		p.nsAnnotationDrop = append(p.nsAnnotationDrop, tagFilter)
 	}
 
+	if err := p.initFilters(); err != nil {
+		return err
+	}
+
 	ctx := context.Background()
 	if p.ResponseTimeout != 0 {
 		p.HTTPClientConfig.Timeout = p.ResponseTimeout
@@ -211,6 +227,38 @@ func (p *Prometheus) Init() error {
 	return nil
 }
 
+func (p *Prometheus) initFilters() error {
+	if p.PodAnnotationExclude != nil {
+		podAnnotationExclude, err := filter.Compile(p.PodAnnotationExclude)
+		if err != nil {
+			return fmt.Errorf("error compiling 'pod_annotation_exclude': %w", err)
+		}
+		p.podAnnotationExcludeFilter = podAnnotationExclude
+	}
+	if p.PodAnnotationInclude != nil {
+		podAnnotationInclude, err := filter.Compile(p.PodAnnotationInclude)
+		if err != nil {
+			return fmt.Errorf("error compiling 'pod_annotation_include': %w", err)
+		}
+		p.podAnnotationIncludeFilter = podAnnotationInclude
+	}
+	if p.PodLabelExclude != nil {
+		podLabelExclude, err := filter.Compile(p.PodLabelExclude)
+		if err != nil {
+			return fmt.Errorf("error compiling 'pod_label_exclude': %w", err)
+		}
+		p.podLabelExcludeFilter = podLabelExclude
+	}
+	if p.PodLabelInclude != nil {
+		podLabelInclude, err := filter.Compile(p.PodLabelInclude)
+		if err != nil {
+			return fmt.Errorf("error compiling 'pod_label_include': %w", err)
+		}
+		p.podLabelIncludeFilter = podLabelInclude
+	}
+	return nil
+}
+
 func (p *Prometheus) AddressToURL(u *url.URL, address string) *url.URL {
 	host := address
 	if u.Port() != "" {

plugins/inputs/prometheus/sample.conf

@@ -78,6 +78,13 @@
   # eg. To scrape pods on a specific node
   # kubernetes_field_selector = "spec.nodeName=$HOSTNAME"
 
+  ## Filter which pod annotations and labels will be added to metric tags
+  #
+  # pod_annotation_include = ["annotation-key-1"]
+  # pod_annotation_exclude = ["exclude-me"]
+  # pod_label_include = ["label-key-1"]
+  # pod_label_exclude = ["exclude-me"]
+
   # cache refresh interval to set the interval for re-sync of pods list.
   # Default is 60 minutes.
   # cache_refresh_interval = 60