refactor: enhance file handling and metrics tracking; remove unused bot health tracker

src/routes/files.ts

@@ -1,11 +1,11 @@
 import { createReadStream } from 'node:fs';
-import { unlink } from 'node:fs/promises';
 import { nanoid } from 'nanoid';
 import { findFileByPublicId } from '../db/files';
 import { fileInfoCache } from '../utils/cache';
-import { formatCreatedAt, getErrorMessage } from '../utils/file';
+import { cleanupTempFile, formatCreatedAt, getErrorMessage } from '../utils/file';
 import logger from '../utils/logger';
-import { getFileInfo } from '../utils/telegram';
+import { metricsCollector } from '../utils/metrics';
+import { getFileInfo, type TelegramFileInfo } from '../utils/telegram';
 import { locateZipEntry } from '../utils/zip';
 
 type RequestWithParams = Request & {
@@ -16,30 +16,24 @@ type RequestWithParams = Request & {
 
 const getTelegramFileInfo = async (telegramFileId: string, public_id: string) => {
   const cacheKey = `file_info_${telegramFileId}`;
-  let fileInfo = fileInfoCache.get(cacheKey) as any;
+  let fileInfo = fileInfoCache.get(cacheKey) as TelegramFileInfo | null;
 
   if (!fileInfo) {
+    metricsCollector.recordCacheMiss();
     fileInfo = await getFileInfo(telegramFileId);
     fileInfoCache.set(cacheKey, fileInfo);
     logger.debug('File info cached', { public_id, cacheKey });
   } else {
+    metricsCollector.recordCacheHit();
     logger.debug('File info from cache', { public_id, cacheKey });
   }
 
-  return fileInfo as { file_size: number; mime_type: string; file_path: string; bot_token: string };
+  return fileInfo;
 };
 
 const buildTelegramFileUrl = (filePath: string, botToken: string): string =>
   `https://api.telegram.org/file/bot${botToken}/${filePath}`;
 
-const cleanupTempFile = async (tempPath: string): Promise<void> => {
-  try {
-    await unlink(tempPath);
-  } catch (err) {
-    logger.warn('Failed to cleanup temp file', { tempPath, error: getErrorMessage(err) });
-  }
-};
-
 const sanitizeFilenameHeader = (fileName: string): string =>
   fileName.replace(/[\\"]/g, '').replace(/[\n\r]/g, '');
 
@@ -93,7 +87,7 @@ export const handleFileRedirect = async (req: RequestWithParams): Promise<Respon
         void cleanupTempFile(tempZipPath);
       });
 
-      return new Response(fileStream as any, {
+      return new Response(fileStream as unknown as ReadableStream, {
         status: 200,
         headers: {
           'Content-Type': file.mimeType || 'application/octet-stream',

src/routes/upload.ts

@@ -1,11 +1,11 @@
 import { createWriteStream } from 'node:fs';
-import { unlink } from 'node:fs/promises';
 import { nanoid } from 'nanoid';
 import { findFileByHash } from '../db/files';
 import { config } from '../env';
 import {
   buildUploadResponse,
   checkFileSize,
+  cleanupTempFile,
   computeHash,
   ensureExtension,
   extractMimeType,
@@ -13,6 +13,7 @@ import {
   getFileType,
 } from '../utils/file';
 import logger from '../utils/logger';
+import { metricsCollector } from '../utils/metrics';
 import { enqueuePreparedUpload, type PreparedUpload } from '../utils/uploadBatcher';
 
 interface JsonUploadPayload {
@@ -56,14 +57,6 @@ const rejectOversizedRequest = (req: Request): Response | null => {
   return null;
 };
 
-const cleanupTempFile = async (tempPath: string): Promise<void> => {
-  try {
-    await unlink(tempPath);
-  } catch (err) {
-    logger.warn('Failed to cleanup temp file', { tempPath, error: getErrorMessage(err) });
-  }
-};
-
 const streamFileToTemp = async (file: File, maxSizeBytes: number): Promise<PreparedUpload> => {
   const tempPath = `/tmp/teleuploader-${nanoid()}`;
   const writer = createWriteStream(tempPath);
@@ -145,6 +138,7 @@ const writeBufferToTemp = async (fileBuffer: Buffer, fileHash: string): Promise<
 };
 
 export const handleUpload = async (req: Request): Promise<Response> => {
+  const startTime = performance.now();
   try {
     const contentType = req.headers.get('content-type') || '';
     const oversizedResponse = rejectOversizedRequest(req);
@@ -161,9 +155,12 @@ export const handleUpload = async (req: Request): Promise<Response> => {
       { status: 400 },
     );
   } catch (error: unknown) {
+    metricsCollector.recordError();
     const message = getErrorMessage(error);
     logger.error('Upload error', { error: message });
     return Response.json({ error: message }, { status: 500 });
+  } finally {
+    metricsCollector.recordUploadTime(performance.now() - startTime);
   }
 };