chore(server): improve stream read (#10960)

packages/backend/server/src/plugins/copilot/context/utils.ts

@@ -2,7 +2,7 @@ import { Readable } from 'node:stream';
 
 import { PrismaClient } from '@prisma/client';
 
-import { BlobQuotaExceeded } from '../../../base';
+import { readBufferWithLimit } from '../../../base';
 import { MAX_EMBEDDABLE_SIZE } from './types';
 
 export class GqlSignal implements AsyncDisposable {
@@ -31,27 +31,6 @@ export async function checkEmbeddingAvailable(
 export function readStream(
   readable: Readable,
   maxSize = MAX_EMBEDDABLE_SIZE
-): Promise<Buffer<ArrayBuffer>> {
-  return new Promise<Buffer<ArrayBuffer>>((resolve, reject) => {
-    const chunks: Uint8Array[] = [];
-    let totalSize = 0;
-
-    readable.on('data', chunk => {
-      totalSize += chunk.length;
-      if (totalSize > maxSize) {
-        reject(new BlobQuotaExceeded());
-        readable.destroy(new BlobQuotaExceeded());
-        return;
-      }
-      chunks.push(chunk);
-    });
-
-    readable.on('end', () => {
-      resolve(Buffer.concat(chunks, totalSize));
-    });
-
-    readable.on('error', err => {
-      reject(err);
-    });
-  });
+): Promise<Buffer> {
+  return readBufferWithLimit(readable, maxSize);
 }

packages/backend/server/src/plugins/copilot/storage.ts

@@ -8,6 +8,7 @@ import {
   CallMetric,
   Config,
   type FileUpload,
+  readBuffer,
   type StorageProvider,
   StorageProviderFactory,
   URLHelper,
@@ -63,29 +64,7 @@ export class CopilotStorage {
       throw new BlobQuotaExceeded();
     }
 
-    const buffer = await new Promise<Buffer>((resolve, reject) => {
-      const stream = blob.createReadStream();
-      const chunks: Uint8Array[] = [];
-      stream.on('data', chunk => {
-        chunks.push(chunk);
-
-        // check size after receive each chunk to avoid unnecessary memory usage
-        const bufferSize = chunks.reduce((acc, cur) => acc + cur.length, 0);
-        if (checkExceeded(bufferSize)) {
-          reject(new BlobQuotaExceeded());
-        }
-      });
-      stream.on('error', reject);
-      stream.on('end', () => {
-        const buffer = Buffer.concat(chunks);
-
-        if (checkExceeded(buffer.length)) {
-          reject(new BlobQuotaExceeded());
-        } else {
-          resolve(buffer);
-        }
-      });
-    });
+    const buffer = await readBuffer(blob.createReadStream(), checkExceeded);
 
     return {
       buffer,