feat(stats): add vehicle data source metadata

go/vehicle-gateway/internal/stats/source.go

@@ -0,0 +1,68 @@
+package stats
+
+import (
+	"context"
+	"strings"
+	"time"
+
+	"lingniu-vehicle-ingest/go/vehicle-gateway/internal/envelope"
+)
+
+type SourceIdentity struct {
+	Protocol       envelope.Protocol
+	SourceIP       string
+	SourceEndpoint string
+}
+
+func NewSourceIdentity(protocol envelope.Protocol, endpoint string) (SourceIdentity, bool) {
+	sourceIP := NormalizeSourceIP(endpoint)
+	if sourceIP == "" {
+		return SourceIdentity{}, false
+	}
+	return SourceIdentity{
+		Protocol:       protocol,
+		SourceIP:       sourceIP,
+		SourceEndpoint: strings.TrimSpace(endpoint),
+	}, true
+}
+
+func NormalizeSourceIP(endpoint string) string {
+	endpoint = strings.TrimSpace(endpoint)
+	if endpoint == "" {
+		return ""
+	}
+	if host, _, ok := strings.Cut(endpoint, ":"); ok {
+		return strings.TrimSpace(host)
+	}
+	return endpoint
+}
+
+func UpsertDataSource(ctx context.Context, exec Execer, identity SourceIdentity, now time.Time) error {
+	if exec == nil {
+		panic("stats execer must not be nil")
+	}
+	if identity.SourceIP == "" {
+		return nil
+	}
+	if now.IsZero() {
+		now = time.Now()
+	}
+	_, err := exec.ExecContext(ctx, upsertDataSourceSQL,
+		string(identity.Protocol),
+		identity.SourceIP,
+		identity.SourceEndpoint,
+		now,
+		now,
+	)
+	return err
+}
+
+const upsertDataSourceSQL = `
+INSERT INTO vehicle_data_source
+  (protocol, source_ip, latest_source_endpoint, first_seen_at, latest_seen_at)
+VALUES (?, ?, ?, ?, ?)
+ON DUPLICATE KEY UPDATE
+  latest_source_endpoint = VALUES(latest_source_endpoint),
+  latest_seen_at = VALUES(latest_seen_at),
+  updated_at = CURRENT_TIMESTAMP
+`