feat: add NodeExporter metrics parsing and update sender to use new structure

Author: guiyumin

internal/prometheus/parser.go …ernal/prometheus/node_exporter_parser.gointernal/prometheus/parser.go renamed to internal/prometheus/node_exporter_parser.go internal/prometheus/parser.go renamed to internal/prometheus/node_exporter_parser.go

@@ -9,9 +9,10 @@ import (
 	"time"
 )
 
-// MetricSnapshot represents a parsed snapshot of all essential metrics
+// NodeExporterMetricSnapshot represents a parsed snapshot of node_exporter metrics
 // This matches the admiral.metrics table schema (raw values, no percentages)
-type MetricSnapshot struct {
+// Specifically designed for Prometheus node_exporter metrics only
+type NodeExporterMetricSnapshot struct {
 	Timestamp time.Time `json:"timestamp"`
 
 	// CPU Metrics (seconds, raw values from counters)
@@ -72,10 +73,11 @@ type MetricSnapshot struct {
 	UptimeSeconds int64 `json:"uptime_seconds"`
 }
 
-// ParsePrometheusMetrics parses Prometheus text format and extracts essential metrics
-// Returns a MetricSnapshot with raw counter values (no percentages calculated)
-func ParsePrometheusMetrics(data []byte) (*MetricSnapshot, error) {
-	snapshot := &MetricSnapshot{
+// ParseNodeExporterMetrics parses Prometheus node_exporter text format and extracts essential metrics
+// Returns a NodeExporterMetricSnapshot with raw counter values (no percentages calculated)
+// This parser is specifically designed for node_exporter metrics only
+func ParseNodeExporterMetrics(data []byte) (*NodeExporterMetricSnapshot, error) {
+	snapshot := &NodeExporterMetricSnapshot{
 		Timestamp: time.Now().UTC(),
 	}
 
@@ -155,7 +157,7 @@ type diskMetrics struct {
 	ioTimeSeconds   float64
 }
 
-func parseLine(line string, snapshot *MetricSnapshot,
+func parseLine(line string, snapshot *NodeExporterMetricSnapshot,
 	cpuIdle, cpuUser, cpuSystem, cpuIowait, cpuSteal map[string]float64,
 	networkDevices map[string]*networkMetrics,
 	diskDevices map[string]*diskMetrics) error {
@@ -429,7 +431,7 @@ func isPhysicalNetwork(device string) bool {
 	return true
 }
 
-func selectPrimaryNetwork(snapshot *MetricSnapshot, devices map[string]*networkMetrics) {
+func selectPrimaryNetwork(snapshot *NodeExporterMetricSnapshot, devices map[string]*networkMetrics) {
 	// Priority: eth0 > en0 > first available
 	var primary *networkMetrics
 	if devices["eth0"] != nil {
@@ -456,7 +458,7 @@ func selectPrimaryNetwork(snapshot *MetricSnapshot, devices map[string]*networkM
 	}
 }
 
-func selectPrimaryDisk(snapshot *MetricSnapshot, devices map[string]*diskMetrics) {
+func selectPrimaryDisk(snapshot *NodeExporterMetricSnapshot, devices map[string]*diskMetrics) {
 	// Priority: vda > sda > nvme0n1 > first available
 	var primary *diskMetrics
 	if devices["vda"] != nil {

internal/prometheus/parser_test.go …/prometheus/node_exporter_parser_test.gointernal/prometheus/parser_test.go renamed to internal/prometheus/node_exporter_parser_test.go internal/prometheus/parser_test.go renamed to internal/prometheus/node_exporter_parser_test.go

@@ -6,17 +6,17 @@ import (
 	"testing"
 )
 
-func TestParsePrometheusMetrics(t *testing.T) {
+func TestParseNodeExporterMetrics(t *testing.T) {
 	// Read the metrics.txt file from the current directory
 	metricFile := "metrics.txt"
 	data, err := os.ReadFile(metricFile)
 	if err != nil {
 		t.Fatalf("Failed to read metrics.txt: %v", err)
 	}
 
-	snapshot, err := ParsePrometheusMetrics(data)
+	snapshot, err := ParseNodeExporterMetrics(data)
 	if err != nil {
-		t.Fatalf("ParsePrometheusMetrics failed: %v", err)
+		t.Fatalf("ParseNodeExporterMetrics failed: %v", err)
 	}
 
 	// Verify timestamp is set
@@ -189,7 +189,7 @@ func TestParsePrometheusMetrics(t *testing.T) {
 		t.Log(string(jsonData))
 
 		// Verify JSON can be unmarshaled back
-		var decoded MetricSnapshot
+		var decoded NodeExporterMetricSnapshot
 		if err := json.Unmarshal(jsonData, &decoded); err != nil {
 			t.Fatalf("Failed to unmarshal JSON: %v", err)
 		}
@@ -220,8 +220,8 @@ func TestParsePrometheusMetrics(t *testing.T) {
 	})
 }
 
-func TestParsePrometheusMetrics_EmptyInput(t *testing.T) {
-	snapshot, err := ParsePrometheusMetrics([]byte{})
+func TestParseNodeExporterMetrics_EmptyInput(t *testing.T) {
+	snapshot, err := ParseNodeExporterMetrics([]byte{})
 	if err != nil {
 		t.Fatalf("Should handle empty input: %v", err)
 	}
@@ -236,9 +236,9 @@ func TestParsePrometheusMetrics_EmptyInput(t *testing.T) {
 	}
 }
 
-func TestParsePrometheusMetrics_InvalidInput(t *testing.T) {
+func TestParseNodeExporterMetrics_InvalidInput(t *testing.T) {
 	invalidData := []byte("invalid prometheus format\ngarbage data")
-	snapshot, err := ParsePrometheusMetrics(invalidData)
+	snapshot, err := ParseNodeExporterMetrics(invalidData)
 
 	if err != nil {
 		t.Fatalf("Should handle invalid input gracefully: %v", err)

internal/report/sender.go

@@ -185,7 +185,7 @@ func (s *Sender) processBatch(filePaths []string) error {
 	}
 
 	// Group entries by exporter name
-	exporterMetrics := make(map[string][]prometheus.MetricSnapshot)
+	exporterMetrics := make(map[string][]prometheus.NodeExporterMetricSnapshot)
 	processedFiles := []string{}
 	var serverID string
 
@@ -217,14 +217,15 @@ func (s *Sender) processBatch(filePaths []string) error {
 		}
 
 		// Parse Prometheus text to structured metrics
-		snapshot, err := prometheus.ParsePrometheusMetrics(entry.Data)
+		// Note: Currently only node_exporter is parsed, other exporters need their own parsers
+		snapshot, err := prometheus.ParseNodeExporterMetrics(entry.Data)
 		if err != nil {
-			logger.Warn("Failed to parse Prometheus metrics, using zero values",
+			logger.Warn("Failed to parse node_exporter metrics, using zero values",
 				logger.String("exporter", entry.ExporterName),
 				logger.String("file", filePath),
 				logger.Err(err))
 			// Use zero-value snapshot
-			snapshot = &prometheus.MetricSnapshot{
+			snapshot = &prometheus.NodeExporterMetricSnapshot{
 				Timestamp: time.Now().UTC(),
 			}
 		}