fix(netflow): изолировать коллектор IPFIX и срезать раздувание базы

Co-authored-by: Cursor <[email protected]>

backend/src/services/traffic-flow-parse.ts

@@ -19,8 +19,26 @@ interface Template {
   fields: FieldSpec[]
 }
 
+const MAX_TEMPLATE_EXPORTERS = 256
 const templatesByExporter = new Map<string, Map<number, Template>>()
 
+function templatesForExporter(exporter: string): Map<number, Template> {
+  const existing = templatesByExporter.get(exporter)
+  if (existing) {
+    templatesByExporter.delete(exporter)
+    templatesByExporter.set(exporter, existing)
+    return existing
+  }
+  const created = new Map<number, Template>()
+  templatesByExporter.set(exporter, created)
+  while (templatesByExporter.size > MAX_TEMPLATE_EXPORTERS) {
+    const oldest = templatesByExporter.keys().next().value
+    if (oldest == null || oldest === exporter) break
+    templatesByExporter.delete(oldest)
+  }
+  return created
+}
+
 function ipv4(buf: Buffer, offset: number): string {
   return `${buf[offset]}.${buf[offset + 1]}.${buf[offset + 2]}.${buf[offset + 3]}`
 }
@@ -105,7 +123,7 @@ function parseNetflowV5(buf: Buffer): ParsedFlow[] {
 
 function parseIpfixTemplates(exporter: string, buf: Buffer, setStart: number, setEnd: number, setId: number) {
   let off = setStart + 4
-  const map = templatesByExporter.get(exporter) ?? new Map<number, Template>()
+  const map = templatesForExporter(exporter)
   while (off + 4 <= setEnd) {
     const templateId = buf.readUInt16BE(off)
     const fieldCount = buf.readUInt16BE(off + 2)
@@ -255,7 +273,7 @@ function parseNetflowV9(buf: Buffer, exporter: string): ParsedFlow[] {
   const count = buf.readUInt16BE(2)
   let off = 20
   const out: ParsedFlow[] = []
-  const map = templatesByExporter.get(exporter) ?? new Map<number, Template>()
+  const map = templatesForExporter(exporter)
   for (let s = 0; s < count && off + 4 <= buf.length; s++) {
     const setId = buf.readUInt16BE(off)
     const setLen = buf.readUInt16BE(off + 2)
@@ -308,3 +326,7 @@ export function protoName(proto: number): string {
 export function resetFlowTemplatesForTests() {
   templatesByExporter.clear()
 }
+
+export function templateExporterCountForTests(): number {
+  return templatesByExporter.size
+}