[k8sclusterreceiver] add k8s.node.condition metric (open-telemetry#27838)

**Description:** <Describe what has changed.>
<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->

Add new k8s.node.condition metric, so that we can deprecate
k8s.node.condition_* metrics.


**Link to tracking Issue:** <Issue number if applicable>


open-telemetry#27617

**Testing:** <Describe what testing was performed and which tests were
added.>

- added unit tests

**Documentation:** <Describe the documentation added.>

- added docs

Author: povilasv

.chloggen/k8sclusterreceiver-add-k8s-node-condition.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: k8sclusterreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "add k8s.node.condition metric"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [27617]
+
+# (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: [user]

receiver/k8sclusterreceiver/documentation.md

@@ -396,6 +396,20 @@ metrics:
     enabled: true
 ```
 
+### k8s.node.condition
+
+The condition of a particular Node.
+
+| Unit | Metric Type | Value Type |
+| ---- | ----------- | ---------- |
+| {condition} | Gauge | Int |
+
+#### Attributes
+
+| Name | Description | Values |
+| ---- | ----------- | ------ |
+| condition | the name of Kubernetes Node condition. Example: Ready, Memory, PID, DiskPressure | Any Str |
+
 ### k8s.pod.status_reason
 
 Current status reason of the pod (1 - Evicted, 2 - NodeAffinity, 3 - NodeLost, 4 - Shutdown, 5 - UnexpectedAdmissionError, 6 - Unknown)

receiver/k8sclusterreceiver/internal/collection/collector.go

@@ -69,6 +69,7 @@ func (dc *DataCollector) CollectMetricData(currentTime time.Time) pmetric.Metric
 		if crm.ScopeMetrics().Len() > 0 {
 			crm.MoveTo(customRMs.AppendEmpty())
 		}
+		node.RecordMetrics(dc.metricsBuilder, o.(*corev1.Node), ts)
 	})
 	dc.metadataStore.ForEach(gvk.Namespace, func(o any) {
 		namespace.RecordMetrics(dc.metricsBuilder, o.(*corev1.Namespace), ts)

receiver/k8sclusterreceiver/internal/metadata/generated_config.go

@@ -55,6 +55,8 @@ all_set:
       enabled: true
     k8s.namespace.phase:
       enabled: true
+    k8s.node.condition:
+      enabled: true
     k8s.pod.phase:
       enabled: true
     k8s.pod.status_reason:
@@ -210,6 +212,8 @@ none_set:
       enabled: false
     k8s.namespace.phase:
       enabled: false
+    k8s.node.condition:
+      enabled: false
     k8s.pod.phase:
       enabled: false
     k8s.pod.status_reason:

receiver/k8sclusterreceiver/internal/metadata/generated_config_test.go

@@ -18,6 +18,7 @@ import (
 	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/common/maps"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/pkg/experimentalmetricmetadata"
 	"github.com/open-telemetry/opentelemetry-collector-contrib/receiver/k8sclusterreceiver/internal/metadata"
+	imetadata "github.com/open-telemetry/opentelemetry-collector-contrib/receiver/k8sclusterreceiver/internal/metadata"
 )
 
 const (
@@ -47,6 +48,19 @@ func Transform(node *corev1.Node) *corev1.Node {
 	return newNode
 }
 
+func RecordMetrics(mb *imetadata.MetricsBuilder, node *corev1.Node, ts pcommon.Timestamp) {
+	for _, c := range node.Status.Conditions {
+		mb.RecordK8sNodeConditionDataPoint(ts, nodeConditionValues[c.Status], string(c.Type))
+	}
+	rb := mb.NewResourceBuilder()
+	rb.SetK8sNodeUID(string(node.UID))
+	rb.SetK8sNodeName(node.Name)
+	rb.SetK8sKubeletVersion(node.Status.NodeInfo.KubeletVersion)
+	rb.SetK8sKubeproxyVersion(node.Status.NodeInfo.KubeProxyVersion)
+
+	mb.EmitForResource(imetadata.WithResource(rb.Emit()))
+}
+
 func CustomMetrics(set receiver.CreateSettings, rb *metadata.ResourceBuilder, node *corev1.Node, nodeConditionTypesToReport,
 	allocatableTypesToReport []string, ts pcommon.Timestamp) pmetric.ResourceMetrics {
 	rm := pmetric.NewResourceMetrics()

receiver/k8sclusterreceiver/internal/metadata/generated_metrics.go

@@ -158,6 +158,30 @@ func TestNodeConditionValue(t *testing.T) {
 	}
 }
 
+func TestNodeMetrics(t *testing.T) {
+	n := testutils.NewNode("1")
+
+	ts := pcommon.Timestamp(time.Now().UnixNano())
+	mbc := metadata.DefaultMetricsBuilderConfig()
+	mbc.Metrics.K8sNodeCondition.Enabled = true
+	mb := metadata.NewMetricsBuilder(mbc, receivertest.NewNopCreateSettings())
+	RecordMetrics(mb, n, ts)
+	m := mb.Emit()
+
+	expectedFile := filepath.Join("testdata", "expected_mdatagen.yaml")
+	expected, err := golden.ReadMetrics(expectedFile)
+	require.NoError(t, err)
+	require.NoError(t, pmetrictest.CompareMetrics(expected, m,
+		pmetrictest.IgnoreTimestamp(),
+		pmetrictest.IgnoreStartTimestamp(),
+		pmetrictest.IgnoreResourceMetricsOrder(),
+		pmetrictest.IgnoreMetricsOrder(),
+		pmetrictest.IgnoreScopeMetricsOrder(),
+		pmetrictest.IgnoreMetricDataPointsOrder(),
+	),
+	)
+}
+
 func TestTransform(t *testing.T) {
 	originalNode := &corev1.Node{
 		ObjectMeta: metav1.ObjectMeta{