perf(mileage): stream workbook export rows

vehicle-data-platform/apps/web/src/v2/domain/mileageExport.test.ts

@@ -1,5 +1,5 @@
 import { afterEach, expect, test, vi } from 'vitest';
-import { downloadMileageWorkbook } from './mileageExport';
+import { createMileageExportStream, downloadMileageWorkbook } from './mileageExport';
 import { createMileageWorkbook } from './mileageWorkbook';
 
 afterEach(() => vi.unstubAllGlobals());
@@ -81,12 +81,35 @@ test('terminates the workbook worker when an active export is cancelled', async
     dateTo: '2026-07-14',
     dates: ['2026-07-13', '2026-07-14'],
     vehicles: [],
-    mileageRows: [],
+    mileageRows: [{ vin: 'LTEST000000000001', plate: '粤A12345', date: '2026-07-13', startMileageKm: 100, endMileageKm: 188.7, dailyMileageKm: 88.7, source: 'GB32960' }],
     sources: []
   }, controller.signal);
 
-  expect(postMessage).toHaveBeenCalledTimes(1);
+  expect(postMessage).toHaveBeenCalledTimes(3);
+  expect(postMessage.mock.calls.map(([message]) => message.type)).toEqual(['start', 'rows', 'finish']);
+  expect(postMessage.mock.calls[1][0].rows).toEqual([{ vin: 'LTEST000000000001', date: '2026-07-13', dailyMileageKm: 88.7 }]);
   controller.abort();
   await expect(exportPromise).rejects.toMatchObject({ name: 'AbortError' });
   expect(terminate).toHaveBeenCalledTimes(1);
 });
+
+test('releases a streaming export before finish when the route aborts', async () => {
+  const terminate = vi.fn();
+  const postMessage = vi.fn();
+  class WorkerMock {
+    onmessage: ((event: MessageEvent) => void) | null = null;
+    onerror: ((event: ErrorEvent) => void) | null = null;
+    postMessage = postMessage;
+    terminate = terminate;
+  }
+  vi.stubGlobal('Worker', WorkerMock);
+  const controller = new AbortController();
+  const stream = createMileageExportStream({ dateFrom: '2026-01-01', dateTo: '2026-12-31', dates: [], sources: [] }, controller.signal);
+  stream.appendRows([{ vin: 'VIN001', date: '2026-01-01', dailyMileageKm: 12.5 }]);
+
+  expect(postMessage.mock.calls.map(([message]) => message.type)).toEqual(['start', 'rows']);
+  controller.abort();
+
+  expect(terminate).toHaveBeenCalledTimes(1);
+  await expect(stream.finish([{ vin: 'VIN001', plate: '粤A00001' }])).rejects.toMatchObject({ name: 'AbortError' });
+});

vehicle-data-platform/apps/web/src/v2/domain/mileageExport.ts

@@ -3,18 +3,23 @@ import { downloadBlob } from './download';
 
 export type MileageExportVehicle = { vin: string; plate: string };
 export type MileageExportSource = { protocol: string; label: string; mileageType: string };
+export type MileageWorkbookRow = Pick<DailyMileageRow, 'vin' | 'date' | 'dailyMileageKm'> & Partial<Omit<DailyMileageRow, 'vin' | 'date' | 'dailyMileageKm'>>;
 
 export type MileageExportInput = {
   dateFrom: string;
   dateTo: string;
   dates: string[];
   vehicles: MileageExportVehicle[];
-  mileageRows: DailyMileageRow[];
+  mileageRows: MileageWorkbookRow[];
   sources: MileageExportSource[];
   exportedAt?: Date;
 };
 
 type MileageWorkerResponse = { ok: true; buffer: ArrayBuffer } | { ok: false; message: string };
+type MileageWorkerRequest =
+  | { type: 'start'; input: Omit<MileageExportInput, 'vehicles' | 'mileageRows'> }
+  | { type: 'rows'; rows: MileageWorkbookRow[] }
+  | { type: 'finish'; vehicles: MileageExportVehicle[] };
 
 function abortError() {
   return new DOMException('里程导出已取消', 'AbortError');
@@ -24,42 +29,88 @@ function throwIfAborted(signal?: AbortSignal) {
   if (signal?.aborted) throw abortError();
 }
 
-async function createMileageWorkbookBuffer(input: MileageExportInput, signal?: AbortSignal) {
+export type MileageExportStream = {
+  appendRows: (rows: readonly MileageWorkbookRow[]) => void;
+  finish: (vehicles: MileageExportVehicle[]) => Promise<void>;
+  dispose: () => void;
+};
+
+export function createMileageExportStream(input: Omit<MileageExportInput, 'vehicles' | 'mileageRows'>, signal?: AbortSignal): MileageExportStream {
   throwIfAborted(signal);
   if (typeof Worker === 'undefined') {
     throw new Error('当前浏览器不支持后台 Excel 导出，请升级到最新版 Chrome、Edge 或 Safari 后重试');
   }
 
-  return new Promise<ArrayBuffer>((resolve, reject) => {
-    const worker = new Worker(new URL('./mileageExport.worker.ts', import.meta.url), { type: 'module' });
-    let settled = false;
-    const cleanup = () => {
-      signal?.removeEventListener('abort', cancel);
-      worker.terminate();
-    };
-    const finish = (callback: () => void) => {
-      if (settled) return;
-      settled = true;
-      cleanup();
-      callback();
-    };
-    const cancel = () => finish(() => reject(abortError()));
-    worker.onmessage = (event: MessageEvent<MileageWorkerResponse>) => {
-      finish(() => event.data.ok ? resolve(event.data.buffer) : reject(new Error(event.data.message)));
-    };
-    worker.onerror = (event) => finish(() => reject(new Error(event.message || 'Excel 工作线程执行失败')));
-    signal?.addEventListener('abort', cancel, { once: true });
-    if (signal?.aborted) {
-      cancel();
+  const worker = new Worker(new URL('./mileageExport.worker.ts', import.meta.url), { type: 'module' });
+  let disposed = false;
+  let finishing = false;
+  let resolveFinish: (() => void) | undefined;
+  let rejectFinish: ((reason?: unknown) => void) | undefined;
+  let earlyError: Error | undefined;
+  const dispose = () => {
+    if (disposed) return;
+    disposed = true;
+    signal?.removeEventListener('abort', cancel);
+    worker.terminate();
+  };
+  const reject = (error: Error) => {
+    if (disposed) return;
+    if (rejectFinish) rejectFinish(error);
+    else earlyError = error;
+    dispose();
+  };
+  const cancel = () => reject(abortError());
+  worker.onmessage = (event: MessageEvent<MileageWorkerResponse>) => {
+    if (disposed) return;
+    if (!event.data.ok) {
+      reject(new Error(event.data.message));
       return;
     }
-    worker.postMessage(input);
-  });
+    const buffer = event.data.buffer;
+    const blob = new Blob([buffer], { type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' });
+    downloadBlob(blob, `车辆里程查询_${input.dateFrom.split('-').join('')}-${input.dateTo.split('-').join('')}_${finishVehicles.length}辆.xlsx`);
+    resolveFinish?.();
+    dispose();
+  };
+  worker.onerror = (event) => reject(new Error(event.message || 'Excel 工作线程执行失败'));
+  signal?.addEventListener('abort', cancel, { once: true });
+  let finishVehicles: MileageExportVehicle[] = [];
+  const post = (message: MileageWorkerRequest) => worker.postMessage(message);
+  post({ type: 'start', input });
+
+  return {
+    appendRows(rows) {
+      if (disposed || finishing) return;
+      post({ type: 'rows', rows: rows.map((row) => ({ vin: row.vin, date: row.date, dailyMileageKm: row.dailyMileageKm })) });
+    },
+    finish(vehicles) {
+      if (disposed) return Promise.reject(earlyError ?? abortError());
+      if (finishing) return Promise.reject(new Error('里程导出已经进入生成阶段'));
+      finishing = true;
+      finishVehicles = vehicles;
+      return new Promise<void>((resolve, rejectPromise) => {
+        resolveFinish = resolve;
+        rejectFinish = rejectPromise;
+        if (earlyError) {
+          rejectPromise(earlyError);
+          dispose();
+          return;
+        }
+        post({ type: 'finish', vehicles });
+      });
+    },
+    dispose
+  };
 }
 
 export async function downloadMileageWorkbook(input: MileageExportInput, signal?: AbortSignal) {
-  const buffer = await createMileageWorkbookBuffer(input, signal);
-  throwIfAborted(signal);
-  const blob = new Blob([buffer], { type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' });
-  downloadBlob(blob, `车辆里程查询_${input.dateFrom.split('-').join('')}-${input.dateTo.split('-').join('')}_${input.vehicles.length}辆.xlsx`);
+  const stream = createMileageExportStream({
+    dateFrom: input.dateFrom,
+    dateTo: input.dateTo,
+    dates: input.dates,
+    sources: input.sources,
+    exportedAt: input.exportedAt
+  }, signal);
+  stream.appendRows(input.mileageRows);
+  await stream.finish(input.vehicles);
 }

vehicle-data-platform/apps/web/src/v2/domain/mileageExport.worker.ts

@@ -1,21 +1,40 @@
-import type { MileageExportInput } from './mileageExport';
+import type { MileageExportInput, MileageWorkbookRow, MileageExportVehicle } from './mileageExport';
 import { createMileageWorkbook } from './mileageWorkbook';
+import { transferableWorkbookBuffer } from './transferableBuffer';
 
 type MileageWorkerResponse = { ok: true; buffer: ArrayBuffer } | { ok: false; message: string };
+type MileageWorkerRequest =
+  | { type: 'start'; input: Omit<MileageExportInput, 'vehicles' | 'mileageRows'> }
+  | { type: 'rows'; rows: MileageWorkbookRow[] }
+  | { type: 'finish'; vehicles: MileageExportVehicle[] };
 type WorkerScope = {
-  onmessage: ((event: MessageEvent<MileageExportInput>) => void) | null;
+  onmessage: ((event: MessageEvent<MileageWorkerRequest>) => void) | null;
   postMessage: (message: MileageWorkerResponse, transfer?: Transferable[]) => void;
 };
 
 const workerScope = self as unknown as WorkerScope;
+let baseInput: Omit<MileageExportInput, 'vehicles' | 'mileageRows'> | undefined;
+let mileageRows: MileageWorkbookRow[] = [];
 
 workerScope.onmessage = async (event) => {
+  if (event.data.type === 'start') {
+    baseInput = event.data.input;
+    mileageRows = [];
+    return;
+  }
+  if (event.data.type === 'rows') {
+    mileageRows.push(...event.data.rows);
+    return;
+  }
   try {
-    const workbook = await createMileageWorkbook(event.data);
+    if (!baseInput) throw new Error('Excel 工作线程未初始化');
+    const workbook = await createMileageWorkbook({ ...baseInput, vehicles: event.data.vehicles, mileageRows });
+    mileageRows = [];
     const output = await workbook.xlsx.writeBuffer();
-    const buffer = new Uint8Array(output as ArrayBuffer).slice().buffer;
+    const buffer = transferableWorkbookBuffer(output as ArrayBuffer | Uint8Array);
     workerScope.postMessage({ ok: true, buffer }, [buffer]);
   } catch (error) {
+    mileageRows = [];
     workerScope.postMessage({
       ok: false,
       message: error instanceof Error ? error.message : 'Excel 工作簿生成失败'

vehicle-data-platform/apps/web/src/v2/domain/mileageWorkbook.ts

@@ -1,5 +1,4 @@
-import type { DailyMileageRow } from '../../api/types';
-import type { MileageExportInput } from './mileageExport';
+import type { MileageExportInput, MileageWorkbookRow } from './mileageExport';
 
 function excelColumn(index: number) {
   let value = index;
@@ -87,14 +86,14 @@ export async function createMileageWorkbook(input: MileageExportInput) {
     if (isDateHeader) cell.numFmt = 'm/d';
   });
 
-  const rowsByVin = new Map<string, Map<string, DailyMileageRow>>();
+  const rowsByVin = new Map<string, Map<string, MileageWorkbookRow>>();
   for (const row of input.mileageRows) {
     if (!rowsByVin.has(row.vin)) rowsByVin.set(row.vin, new Map());
     rowsByVin.get(row.vin)!.set(row.date, row);
   }
   input.vehicles.forEach((vehicle, index) => {
     const rowNumber = firstDataRow + index;
-    const mileageByDate = rowsByVin.get(vehicle.vin) ?? new Map<string, DailyMileageRow>();
+    const mileageByDate = rowsByVin.get(vehicle.vin) ?? new Map<string, MileageWorkbookRow>();
     const dailyValues = input.dates.map((date) => mileageByDate.get(date)?.dailyMileageKm ?? null);
     const total = dailyValues.reduce<number>((sum, value) => sum + (value ?? 0), 0);
     const row = sheet.getRow(rowNumber);

vehicle-data-platform/apps/web/src/v2/domain/transferableBuffer.test.ts

@@ -0,0 +1,16 @@
+import { expect, test } from 'vitest';
+import { transferableWorkbookBuffer } from './transferableBuffer';
+
+test('reuses complete workbook buffers and only copies partial views', () => {
+  const direct = new ArrayBuffer(8);
+  expect(transferableWorkbookBuffer(direct)).toBe(direct);
+
+  const completeView = new Uint8Array(new ArrayBuffer(8));
+  expect(transferableWorkbookBuffer(completeView)).toBe(completeView.buffer);
+
+  const source = new Uint8Array([1, 2, 3, 4]);
+  const partial = source.subarray(1, 3);
+  const transferred = transferableWorkbookBuffer(partial);
+  expect(transferred).not.toBe(source.buffer);
+  expect([...new Uint8Array(transferred)]).toEqual([2, 3]);
+});

vehicle-data-platform/apps/web/src/v2/domain/transferableBuffer.ts

@@ -0,0 +1,7 @@
+export function transferableWorkbookBuffer(output: ArrayBuffer | Uint8Array): ArrayBuffer {
+  if (output instanceof ArrayBuffer) return output;
+  if (output.buffer instanceof ArrayBuffer && output.byteOffset === 0 && output.byteLength === output.buffer.byteLength) {
+    return output.buffer;
+  }
+  return output.slice().buffer as ArrayBuffer;
+}