[receiver/k8sobjects] Add ability to exclude deleted updates for watc…

…hed objects (#26042)

**Description:** 
Adds a new configuration option that allows excluding `DELETED` updates
for watched objects.

**Link to tracking Issue:** 
Closes
#24904

**Testing:** 
New unit tests and tested locally

**Documentation:**
Updated the readme

.chloggen/k8sobjects-filter-delete.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: k8sobjectreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Adds option to exclude event types (MODIFIED, DELETED, etc) in watch mode.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [26042]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

receiver/k8sobjectsreceiver/README.md

@@ -50,6 +50,7 @@ the K8s API server. This can be one of `none` (for no auth), `serviceAccount`
 - `label_selector`: select objects by label(s)
 - `field_selector`: select objects by field(s)
 - `interval`: the interval at which object is pulled, default 60 minutes. Only useful for `pull` mode.
+- `exclude_watch_type`: allows excluding specific watch types. Valid values are `ADDED`, `MODIFIED`, `DELETED`, `BOOKMARK`, and `ERROR`. Only usable in `watch` mode.
 - `resource_version` allows watch resources starting from a specific version (default = `1`). Only available for `watch` mode. If not specified, the receiver will do an initial list to get the resourceVersion before starting the watch. See [Efficient Detection of Change](https://kubernetes.io/docs/reference/using-api/api-concepts/#efficient-detection-of-changes) for details on why this is necessary.
 - `namespaces`: An array of `namespaces` to collect events from. (default = `all`)
 - `group`: API group name. It is an optional config. When given resource object is present in multiple groups,

receiver/k8sobjectsreceiver/config.go

@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	apiWatch "k8s.io/apimachinery/pkg/watch"
 	"k8s.io/client-go/discovery"
 	"k8s.io/client-go/dynamic"
 
@@ -32,15 +33,17 @@ var modeMap = map[mode]bool{
 }
 
 type K8sObjectsConfig struct {
-	Name            string        `mapstructure:"name"`
-	Group           string        `mapstructure:"group"`
-	Namespaces      []string      `mapstructure:"namespaces"`
-	Mode            mode          `mapstructure:"mode"`
-	LabelSelector   string        `mapstructure:"label_selector"`
-	FieldSelector   string        `mapstructure:"field_selector"`
-	Interval        time.Duration `mapstructure:"interval"`
-	ResourceVersion string        `mapstructure:"resource_version"`
-	gvr             *schema.GroupVersionResource
+	Name             string               `mapstructure:"name"`
+	Group            string               `mapstructure:"group"`
+	Namespaces       []string             `mapstructure:"namespaces"`
+	Mode             mode                 `mapstructure:"mode"`
+	LabelSelector    string               `mapstructure:"label_selector"`
+	FieldSelector    string               `mapstructure:"field_selector"`
+	Interval         time.Duration        `mapstructure:"interval"`
+	ResourceVersion  string               `mapstructure:"resource_version"`
+	ExcludeWatchType []apiWatch.EventType `mapstructure:"exclude_watch_type"`
+	exclude          map[apiWatch.EventType]bool
+	gvr              *schema.GroupVersionResource
 }
 
 type Config struct {
@@ -87,6 +90,10 @@ func (c *Config) Validate() error {
 			object.Interval = defaultPullInterval
 		}
 
+		if object.Mode == PullMode && len(object.ExcludeWatchType) != 0 {
+			return fmt.Errorf("the Exclude config can only be used with watch mode")
+		}
+
 		object.gvr = gvr
 	}
 	return nil

receiver/k8sobjectsreceiver/config_test.go

@@ -13,6 +13,7 @@ import (
 	"go.opentelemetry.io/collector/component"
 	"go.opentelemetry.io/collector/confmap/confmaptest"
 	"k8s.io/apimachinery/pkg/runtime/schema"
+	apiWatch "k8s.io/apimachinery/pkg/watch"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/k8sconfig"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/receiver/k8sobjectsreceiver/internal/metadata"
@@ -50,6 +51,9 @@ func TestLoadConfig(t *testing.T) {
 						Namespaces:      []string{"default"},
 						Group:           "events.k8s.io",
 						ResourceVersion: "",
+						ExcludeWatchType: []apiWatch.EventType{
+							apiWatch.Deleted,
+						},
 						gvr: &schema.GroupVersionResource{
 							Group:    "events.k8s.io",
 							Version:  "v1",
@@ -130,6 +134,9 @@ func TestLoadConfig(t *testing.T) {
 		{
 			id: component.NewIDWithName(metadata.Type, "invalid_resource"),
 		},
+		{
+			id: component.NewIDWithName(metadata.Type, "exclude_deleted_with_pull"),
+		},
 	}
 
 	for _, tt := range tests {

receiver/k8sobjectsreceiver/mock_dynamic_client_test.go

@@ -47,6 +47,16 @@ func (c mockDynamicClient) createPods(objects ...*unstructured.Unstructured) {
 	}
 }
 
+func (c mockDynamicClient) deletePods(objects ...*unstructured.Unstructured) {
+	pods := c.client.Resource(schema.GroupVersionResource{
+		Version:  "v1",
+		Resource: "pods",
+	})
+	for _, pod := range objects {
+		_ = pods.Namespace(pod.GetNamespace()).Delete(context.Background(), pod.GetName(), v1.DeleteOptions{})
+	}
+}
+
 func generatePod(name, namespace string, labels map[string]interface{}, resourceVersion string) *unstructured.Unstructured {
 	pod := unstructured.Unstructured{
 		Object: map[string]interface{}{

receiver/k8sobjectsreceiver/receiver.go

@@ -49,6 +49,13 @@ func newReceiver(params receiver.CreateSettings, config *Config, consumer consum
 		return nil, err
 	}
 
+	for _, object := range config.Objects {
+		object.exclude = make(map[apiWatch.EventType]bool)
+		for _, item := range object.ExcludeWatchType {
+			object.exclude[item] = true
+		}
+	}
+
 	return &k8sobjectsreceiver{
 		client:   client,
 		setting:  params,
@@ -172,6 +179,12 @@ func (kr *k8sobjectsreceiver) startWatch(ctx context.Context, config *K8sObjects
 				kr.setting.Logger.Warn("Watch channel closed unexpectedly", zap.String("resource", config.gvr.String()))
 				return
 			}
+
+			if config.exclude[data.Type] {
+				kr.setting.Logger.Debug("dropping excluded data", zap.String("type", string(data.Type)))
+				continue
+			}
+
 			logs, err := watchObjectsToLogData(&data, time.Now(), config)
 			if err != nil {
 				kr.setting.Logger.Error("error converting objects to log data", zap.Error(err))

receiver/k8sobjectsreceiver/receiver_test.go

@@ -13,6 +13,7 @@ import (
 	"go.opentelemetry.io/collector/component/componenttest"
 	"go.opentelemetry.io/collector/consumer/consumertest"
 	"go.opentelemetry.io/collector/receiver/receivertest"
+	apiWatch "k8s.io/apimachinery/pkg/watch"
 )
 
 func TestNewReceiver(t *testing.T) {
@@ -136,5 +137,71 @@ func TestWatchObject(t *testing.T) {
 	assert.Len(t, consumer.Logs(), 2)
 	assert.Equal(t, 2, consumer.Count())
 
+	mockClient.deletePods(
+		generatePod("pod2", "default", map[string]interface{}{
+			"environment": "test",
+		}, "2"),
+	)
+	time.Sleep(time.Millisecond * 100)
+	assert.Len(t, consumer.Logs(), 3)
+	assert.Equal(t, 3, consumer.Count())
+
+	assert.NoError(t, r.Shutdown(ctx))
+}
+
+func TestExludeDeletedTrue(t *testing.T) {
+	t.Parallel()
+
+	mockClient := newMockDynamicClient()
+
+	mockClient.createPods(
+		generatePod("pod1", "default", map[string]interface{}{
+			"environment": "production",
+		}, "1"),
+	)
+
+	rCfg := createDefaultConfig().(*Config)
+	rCfg.makeDynamicClient = mockClient.getMockDynamicClient
+	rCfg.makeDiscoveryClient = getMockDiscoveryClient
+
+	rCfg.Objects = []*K8sObjectsConfig{
+		{
+			Name:       "pods",
+			Mode:       WatchMode,
+			Namespaces: []string{"default"},
+			ExcludeWatchType: []apiWatch.EventType{
+				apiWatch.Deleted,
+			},
+		},
+	}
+
+	err := rCfg.Validate()
+	require.NoError(t, err)
+
+	consumer := newMockLogConsumer()
+	r, err := newReceiver(
+		receivertest.NewNopCreateSettings(),
+		rCfg,
+		consumer,
+	)
+
+	ctx := context.Background()
+	require.NoError(t, err)
+	require.NotNil(t, r)
+	require.NoError(t, r.Start(ctx, componenttest.NewNopHost()))
+
+	time.Sleep(time.Millisecond * 100)
+	assert.Len(t, consumer.Logs(), 0)
+	assert.Equal(t, 0, consumer.Count())
+
+	mockClient.deletePods(
+		generatePod("pod1", "default", map[string]interface{}{
+			"environment": "test",
+		}, "1"),
+	)
+	time.Sleep(time.Millisecond * 100)
+	assert.Len(t, consumer.Logs(), 0)
+	assert.Equal(t, 0, consumer.Count())
+
 	assert.NoError(t, r.Shutdown(ctx))
 }

receiver/k8sobjectsreceiver/testdata/config.yaml

@@ -8,6 +8,7 @@ k8sobjects:
       mode: watch
       group: events.k8s.io
       namespaces: [default]
+      exclude_watch_type: [DELETED]
 k8sobjects/pull_with_resource:
   objects:
     - name: pods
@@ -30,3 +31,8 @@ k8sobjects/invalid_resource:
   objects:
     - name: fake_resource
       mode: watch
+k8sobjects/exclude_deleted_with_pull:
+  objects:
+    - name: events
+      mode: pull
+      exclude_watch_type: [DELETED]