fix(sync): 修复云同步多设备冲突下的静默覆盖与状态污染问题

packages/filesystem/baidu/baidu.test.ts

@@ -32,4 +32,167 @@ describe("BaiduFileSystem", () => {
     );
     expect(updateDynamicRulesMock).not.toHaveBeenCalled();
   });
+
+  it("create should reject expectedVersion as unsupported", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+
+    await expect(fs.create("test.txt", { expectedVersion: "version" })).rejects.toMatchObject({
+      provider: "baidu",
+      unsupported: true,
+    });
+  });
+
+  it("writer should reject createOnly when target already exists", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+    vi.spyOn(fs, "list").mockResolvedValue([
+      {
+        name: "test.txt",
+        path: "/apps",
+        size: 1,
+        digest: "md5",
+        createtime: 1,
+        updatetime: 1,
+      },
+    ]);
+
+    const writer = await fs.create("test.txt", { createOnly: true });
+
+    await expect(writer.write("content")).rejects.toMatchObject({
+      provider: "baidu",
+      conflict: true,
+    });
+  });
+
+  it("writer should ask Baidu to fail server-side createOnly collisions", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+    vi.spyOn(fs, "list").mockResolvedValue([]);
+    const requestSpy = vi
+      .spyOn(fs, "request")
+      .mockResolvedValueOnce({ errno: 0, uploadid: "upload-id" })
+      .mockResolvedValueOnce({ errno: 0 })
+      .mockResolvedValueOnce({ errno: 0 });
+
+    const writer = await fs.create("test.txt", { createOnly: true });
+
+    await expect(writer.write("content")).resolves.toBeUndefined();
+
+    expect(String((requestSpy.mock.calls[0][1] as RequestInit).body)).toContain("rtype=0");
+    expect(String((requestSpy.mock.calls[2][1] as RequestInit).body)).toContain("rtype=0");
+  });
+
+  it("writer should surface Baidu createOnly rejection as conflict", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+    vi.spyOn(fs, "list").mockResolvedValue([]);
+    vi.spyOn(fs, "request").mockResolvedValueOnce({ errno: -8, errmsg: "file exists" });
+
+    const writer = await fs.create("test.txt", { createOnly: true });
+
+    await expect(writer.write("content")).rejects.toMatchObject({
+      provider: "baidu",
+      conflict: true,
+    });
+  });
+
+  it("writer should reject expectedDigest when remote digest changed", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+    vi.spyOn(fs, "list").mockResolvedValue([
+      {
+        name: "test.txt",
+        path: "/apps",
+        size: 1,
+        digest: "new-md5",
+        createtime: 1,
+        updatetime: 1,
+      },
+    ]);
+
+    const writer = await fs.create("test.txt", { expectedDigest: "old-md5" });
+
+    await expect(writer.write("content")).rejects.toMatchObject({
+      provider: "baidu",
+      conflict: true,
+    });
+  });
+
+  it("writer should allow best-effort expectedDigest when remote digest still matches", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+    vi.spyOn(fs, "list").mockResolvedValue([
+      {
+        name: "test.txt",
+        path: "/apps",
+        size: 1,
+        digest: "old-md5",
+        createtime: 1,
+        updatetime: 1,
+      },
+    ]);
+    const requestSpy = vi
+      .spyOn(fs, "request")
+      .mockResolvedValueOnce({ errno: 0, uploadid: "upload-id" })
+      .mockResolvedValueOnce({ errno: 0 })
+      .mockResolvedValueOnce({ errno: 0 });
+
+    const writer = await fs.create("test.txt", { expectedDigest: "old-md5" });
+
+    await expect(writer.write("content")).resolves.toBeUndefined();
+    expect(requestSpy).toHaveBeenCalledTimes(3);
+    expect(String((requestSpy.mock.calls[0][1] as RequestInit).body)).toContain("rtype=3");
+    expect(String((requestSpy.mock.calls[2][1] as RequestInit).body)).toContain("rtype=3");
+  });
+
+  it("delete should be idempotent when Baidu reports file missing", async () => {
+    const fetchMock = vi.fn().mockResolvedValue({
+      json: async () => ({ errno: -9 }),
+    });
+    vi.stubGlobal("fetch", fetchMock);
+    const fs = new BaiduFileSystem("/apps", "token");
+
+    await expect(fs.delete("missing.txt")).resolves.toBeUndefined();
+  });
+
+  it("delete should reject expectedVersion as unsupported", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+
+    await expect(fs.delete("test.txt", { expectedVersion: "version" })).rejects.toMatchObject({
+      provider: "baidu",
+      unsupported: true,
+    });
+  });
+
+  it("delete should reject expectedDigest when remote digest changed", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+    vi.spyOn(fs, "list").mockResolvedValue([
+      {
+        name: "test.txt",
+        path: "/apps",
+        size: 1,
+        digest: "new-md5",
+        createtime: 1,
+        updatetime: 1,
+      },
+    ]);
+
+    await expect(fs.delete("test.txt", { expectedDigest: "old-md5" })).rejects.toMatchObject({
+      provider: "baidu",
+      conflict: true,
+    });
+  });
+
+  it("delete should allow best-effort expectedDigest when remote digest still matches", async () => {
+    const fs = new BaiduFileSystem("/apps", "token");
+    vi.spyOn(fs, "list").mockResolvedValue([
+      {
+        name: "test.txt",
+        path: "/apps",
+        size: 1,
+        digest: "old-md5",
+        createtime: 1,
+        updatetime: 1,
+      },
+    ]);
+    const requestSpy = vi.spyOn(fs, "request").mockResolvedValue({ errno: 0 });
+
+    await expect(fs.delete("test.txt", { expectedDigest: "old-md5" })).resolves.toBeUndefined();
+    expect(requestSpy).toHaveBeenCalledTimes(1);
+  });
 });

packages/filesystem/baidu/baidu.ts

@@ -1,6 +1,7 @@
 import { AuthVerify } from "../auth";
+import { fileConflictError, unsupportedConditionalWriteError } from "../error";
 import type FileSystem from "../filesystem";
-import type { FileInfo, FileCreateOptions, FileReader, FileWriter } from "../filesystem";
+import type { FileInfo, FileCreateOptions, FileDeleteOptions, FileReader, FileWriter } from "../filesystem";
 import { joinPath } from "../utils";
 import { BaiduFileReader, BaiduFileWriter } from "./rw";
 
@@ -29,8 +30,14 @@ export default class BaiduFileSystem implements FileSystem {
     return new BaiduFileSystem(joinPath(this.path, path), this.accessToken);
   }
 
-  async create(path: string, _opts?: FileCreateOptions): Promise<FileWriter> {
-    return new BaiduFileWriter(this, joinPath(this.path, path));
+  async create(path: string, opts?: FileCreateOptions): Promise<FileWriter> {
+    if (opts?.expectedVersion) {
+      throw unsupportedConditionalWriteError(
+        "baidu",
+        "Baidu filesystem does not expose a version token for conditional writes"
+      );
+    }
+    return new BaiduFileWriter(this, joinPath(this.path, path), opts);
   }
 
   async createDir(dir: string, _opts?: FileCreateOptions): Promise<void> {
@@ -82,23 +89,43 @@ export default class BaiduFileSystem implements FileSystem {
       });
   }
 
-  delete(path: string): Promise<void> {
+  async delete(path: string, opts?: FileDeleteOptions): Promise<void> {
+    if (opts?.expectedVersion) {
+      throw unsupportedConditionalWriteError(
+        "baidu",
+        "Baidu filesystem does not expose a version token for conditional deletes"
+      );
+    }
+    if (opts?.expectedDigest) {
+      // 百度网盘删除接口不支持服务端 If-Match/CAS，只能先 list 比对 digest 再删除。
+      // 这只能降低 stale 删除风险，不能关闭“检查后、删除前被其他设备更新”的 TOCTOU 窗口。
+      // 典型残留窗口：A list 通过后，B 更新同名文件，A 随后 delete 仍可能删除 B 的新内容。
+      const targetName = path.substring(path.lastIndexOf("/") + 1);
+      const existing = (await this.list()).find((file) => file.name === targetName);
+      if (existing && existing.digest !== opts.expectedDigest) {
+        throw fileConflictError("baidu", `Baidu file digest changed before delete: ${path}`, {
+          status: 412,
+          code: "digestMismatch",
+        });
+      }
+    }
     const filelist = [joinPath(this.path, path)];
     const myHeaders = new Headers();
     myHeaders.append("Content-Type", "application/x-www-form-urlencoded");
-    return this.request(
+    const data = await this.request(
       `https://pan.baidu.com/rest/2.0/xpan/file?method=filemanager&access_token=${this.accessToken}&opera=delete`,
       {
         method: "POST",
         body: `async=0&filelist=${encodeURIComponent(JSON.stringify(filelist))}`,
         headers: myHeaders,
       }
-    ).then((data) => {
-      if (data.errno) {
-        throw new Error(JSON.stringify(data));
+    );
+    if (data.errno) {
+      if (data.errno === -9 || data.errno === 12) {
+        return;
       }
-      return data;
-    });
+      throw new Error(JSON.stringify(data));
+    }
   }
 
   async list(): Promise<FileInfo[]> {

packages/filesystem/baidu/rw.ts

@@ -1,4 +1,5 @@
-import type { FileInfo, FileReader, FileWriter } from "../filesystem";
+import { fileConflictError } from "../error";
+import type { FileCreateOptions, FileInfo, FileReader, FileWriter } from "../filesystem";
 import { calculateMd5, md5OfText } from "@App/pkg/utils/crypto";
 import type BaiduFileSystem from "./baidu";
 
@@ -38,9 +39,12 @@ export class BaiduFileWriter implements FileWriter {
 
   fs: BaiduFileSystem;
 
-  constructor(fs: BaiduFileSystem, path: string) {
+  opts?: FileCreateOptions;
+
+  constructor(fs: BaiduFileSystem, path: string, opts?: FileCreateOptions) {
     this.fs = fs;
     this.path = path;
+    this.opts = opts;
   }
 
   size(content: string | Blob) {
@@ -58,6 +62,8 @@ export class BaiduFileWriter implements FileWriter {
   }
 
   async write(content: string | Blob): Promise<void> {
+    await this.checkWritePrecondition();
+
     // 预上传获取id
     const size = this.size(content).toString();
     const md5 = await this.md5(content);
@@ -67,7 +73,7 @@ export class BaiduFileWriter implements FileWriter {
     urlencoded.append("size", size);
     urlencoded.append("isdir", "0");
     urlencoded.append("autoinit", "1");
-    urlencoded.append("rtype", "3");
+    urlencoded.append("rtype", this.opts?.createOnly ? "0" : "3");
     urlencoded.append("block_list", JSON.stringify(blockList));
     const myHeaders = new Headers();
     myHeaders.append("Content-Type", "application/x-www-form-urlencoded");
@@ -80,6 +86,7 @@ export class BaiduFileWriter implements FileWriter {
       }
     );
     if (data.errno) {
+      this.throwCreateOnlyConflict(data);
       throw new Error(JSON.stringify(data));
     }
     const uploadid = data.uploadid;
@@ -102,6 +109,7 @@ export class BaiduFileWriter implements FileWriter {
       }
     );
     if (data.errno) {
+      this.throwCreateOnlyConflict(data);
       throw new Error(JSON.stringify(data));
     }
     // 创建文件
@@ -111,7 +119,7 @@ export class BaiduFileWriter implements FileWriter {
     urlencoded.append("isdir", "0");
     urlencoded.append("block_list", JSON.stringify(blockList));
     urlencoded.append("uploadid", uploadid);
-    urlencoded.append("rtype", "3");
+    urlencoded.append("rtype", this.opts?.createOnly ? "0" : "3");
     data = await this.fs.request(
       `https://pan.baidu.com/rest/2.0/xpan/file?method=create&access_token=${this.fs.accessToken}`,
       {
@@ -121,7 +129,46 @@ export class BaiduFileWriter implements FileWriter {
       }
     );
     if (data.errno) {
+      this.throwCreateOnlyConflict(data);
       throw new Error(JSON.stringify(data));
     }
   }
+
+  private throwCreateOnlyConflict(data: any): void {
+    if (!this.opts?.createOnly) {
+      return;
+    }
+    throw fileConflictError("baidu", `File already exists or createOnly write was rejected: ${this.path}`, {
+      status: 409,
+      code: String(data.errno),
+      raw: data,
+    });
+  }
+
+  private async checkWritePrecondition(): Promise<void> {
+    if (!this.opts?.expectedDigest && !this.opts?.createOnly) {
+      return;
+    }
+    const targetName = this.path.substring(this.path.lastIndexOf("/") + 1);
+    const existing = (await this.fs.list()).find((file) => file.name === targetName);
+
+    if (this.opts?.createOnly) {
+      if (existing) {
+        throw fileConflictError("baidu", `File already exists: ${this.path}`, {
+          status: 409,
+          code: "nameAlreadyExists",
+        });
+      }
+      return;
+    }
+
+    // 百度网盘没有原子 compare-and-swap 上传能力；这个 digest 检查只是 best-effort。
+    // 它只能在上传前发现本地快照已过期；createOnly 仍依赖服务端 rtype=0 来拒绝同名覆盖。
+    if (this.opts?.expectedDigest && existing?.digest !== this.opts.expectedDigest) {
+      throw fileConflictError("baidu", `Baidu file digest changed before write: ${this.path}`, {
+        status: 412,
+        code: "digestMismatch",
+      });
+    }
+  }
 }