fix: add label node_name to kepler_node_cpu_info metric

docs/user/metrics.md

@@ -81,6 +81,8 @@ These metrics provide energy and power information at the node level.
   - `model_name`
   - `physical_id`
   - `core_id`
+- **Constant Labels**:
+  - `node_name`
 
 #### kepler_node_cpu_joules_total
 

hack/gen-metric-docs/main.go

@@ -350,7 +350,7 @@ func main() {
 	fmt.Println("Created power collector")
 	buildInfoCollector := collector.NewKeplerBuildInfoCollector()
 	fmt.Println("Created build info collector")
-	cpuInfoCollector, err := collector.NewCPUInfoCollector("/proc")
+	cpuInfoCollector, err := collector.NewCPUInfoCollector("/proc", "test-node")
 	if err != nil {
 		fmt.Printf("Warning: Could not create CPU info collector: %v\n", err)
 	} else {

internal/exporter/prometheus/collector/cpuinfo.go

@@ -41,23 +41,23 @@ type cpuInfoCollector struct {
 }
 
 // NewCPUInfoCollector creates a CPUInfoCollector using a procfs mount path.
-func NewCPUInfoCollector(procPath string) (*cpuInfoCollector, error) {
+func NewCPUInfoCollector(procPath, nodeName string) (*cpuInfoCollector, error) {
 	fs, err := newProcFS(procPath)
 	if err != nil {
 		return nil, fmt.Errorf("creating procfs failed: %w", err)
 	}
-	return newCPUInfoCollectorWithFS(fs), nil
+	return newCPUInfoCollectorWithFS(fs, nodeName), nil
 }
 
 // newCPUInfoCollectorWithFS injects a procFS interface
-func newCPUInfoCollectorWithFS(fs procFS) *cpuInfoCollector {
+func newCPUInfoCollectorWithFS(fs procFS, nodeName string) *cpuInfoCollector {
 	return &cpuInfoCollector{
 		fs: fs,
 		desc: prom.NewDesc(
 			prom.BuildFQName(keplerNS, "node", "cpu_info"),
 			"CPU information from procfs",
 			[]string{"processor", "vendor_id", "model_name", "physical_id", "core_id"},
-			nil,
+			prom.Labels{nodeNameLabel: nodeName},
 		),
 	}
 }

internal/exporter/prometheus/collector/cpuinfo_test.go

@@ -50,13 +50,14 @@ func expectedLabels() map[string]string {
 		"model_name":  "",
 		"physical_id": "",
 		"core_id":     "",
+		"node_name":   "",
 	}
 }
 
 // TestNewCPUInfoCollector tests the creation of a new CPUInfoCollector.
 func TestNewCPUInfoCollector(t *testing.T) {
 	// Test successful creation with a mock procfs
-	collector, err := NewCPUInfoCollector("/proc")
+	collector, err := NewCPUInfoCollector("/proc", "test-node")
 	assert.NoError(t, err)
 	assert.NotNil(t, collector)
 	assert.NotNil(t, collector.fs)
@@ -70,12 +71,13 @@ func TestNewCPUInfoCollectorWithFS(t *testing.T) {
 			return sampleCPUInfo(), nil
 		},
 	}
-	collector := newCPUInfoCollectorWithFS(mockFS)
+	collector := newCPUInfoCollectorWithFS(mockFS, "test-node")
 	assert.NotNil(t, collector)
 	assert.Equal(t, mockFS, collector.fs)
 	assert.NotNil(t, collector.desc)
 	assert.Contains(t, collector.desc.String(), "kepler_node_cpu_info")
 	assert.Contains(t, collector.desc.String(), "variableLabels: {processor,vendor_id,model_name,physical_id,core_id}")
+	assert.Contains(t, collector.desc.String(), `node_name="test-node"`)
 }
 
 // TestCPUInfoCollector_Describe tests the Describe method.
@@ -85,7 +87,7 @@ func TestCPUInfoCollector_Describe(t *testing.T) {
 			return sampleCPUInfo(), nil
 		},
 	}
-	collector := newCPUInfoCollectorWithFS(mockFS)
+	collector := newCPUInfoCollectorWithFS(mockFS, "test-node")
 
 	ch := make(chan *prometheus.Desc, 1)
 	collector.Describe(ch)
@@ -102,7 +104,7 @@ func TestCPUInfoCollector_Collect_Success(t *testing.T) {
 			return sampleCPUInfo(), nil
 		},
 	}
-	collector := newCPUInfoCollectorWithFS(mockFS)
+	collector := newCPUInfoCollectorWithFS(mockFS, "test-node")
 
 	ch := make(chan prometheus.Metric, 10)
 	collector.Collect(ch)
@@ -140,7 +142,7 @@ func TestCPUInfoCollector_Collect_Error(t *testing.T) {
 			return nil, errors.New("failed to read CPU info")
 		},
 	}
-	collector := newCPUInfoCollectorWithFS(mockFS)
+	collector := newCPUInfoCollectorWithFS(mockFS, "test-node")
 
 	ch := make(chan prometheus.Metric, 10)
 	collector.Collect(ch)
@@ -161,7 +163,7 @@ func TestCPUInfoCollector_Collect_Concurrency(t *testing.T) {
 			return sampleCPUInfo(), nil
 		},
 	}
-	collector := newCPUInfoCollectorWithFS(mockFS)
+	collector := newCPUInfoCollectorWithFS(mockFS, "test-node")
 
 	const numGoroutines = 10
 	var wg sync.WaitGroup

internal/exporter/prometheus/prometheus.go

@@ -156,7 +156,7 @@ func CreateCollectors(pm Monitor, applyOpts ...OptionFn) (map[string]prom.Collec
 		"build_info": collector.NewKeplerBuildInfoCollector(),
 		"power":      collector.NewPowerCollector(pm, opts.nodeName, opts.logger, opts.metricsLevel),
 	}
-	cpuInfoCollector, err := collector.NewCPUInfoCollector(opts.procfs)
+	cpuInfoCollector, err := collector.NewCPUInfoCollector(opts.procfs, opts.nodeName)
 	if err != nil {
 		return nil, err
 	}