fix: automatically trigger clear_local when permissions changed

see #7

src/admin/admin.controller.spec.ts

@@ -0,0 +1,29 @@
+import { Test, TestingModule } from '@nestjs/testing';
+import { AdminController } from './admin.controller';
+import { CouchdbService } from '../couchdb/couchdb.service';
+import { authGuardMockProviders } from '../auth/auth-guard-mock.providers';
+import { AdminService } from './admin.service';
+
+describe('AdminController', () => {
+  let controller: AdminController;
+  let mockAdminService: CouchdbService;
+
+  beforeEach(async () => {
+    mockAdminService = {
+      clearLocal: () => Promise.resolve(),
+    } as any;
+    const module: TestingModule = await Test.createTestingModule({
+      controllers: [AdminController],
+      providers: [
+        ...authGuardMockProviders,
+        { provide: AdminService, useValue: mockAdminService },
+      ],
+    }).compile();
+
+    controller = module.get(AdminController);
+  });
+
+  it('should be defined', () => {
+    expect(controller).toBeDefined();
+  });
+});

src/admin/admin.controller.ts

@@ -0,0 +1,30 @@
+import { Controller, Param, Post, UseGuards } from '@nestjs/common';
+import { CombinedAuthGuard } from '../auth/guards/combined-auth/combined-auth.guard';
+import { OnlyAuthenticated } from '../auth/only-authenticated.decorator';
+import { AdminService } from './admin.service';
+
+/**
+ * This service provides some general administrativ endpoints.
+ */
+@OnlyAuthenticated()
+@UseGuards(CombinedAuthGuard)
+@Controller('admin')
+export class AdminController {
+  constructor(private adminService: AdminService) {}
+
+  /**
+   * Deletes all local documents of the remote database.
+   * These document hold meta-information about the replication process.
+   * Deleting them forces clients to re-run sync and check which documents are different.
+   * See {@link https://docs.couchdb.org/en/stable/replication/protocol.html#retrieve-replication-logs-from-source-and-target}
+   *
+   * @param db name of the database where the local documents should be deleted from
+   *
+   * This function should be called whenever the permissions change to re-trigger sync
+   */
+  @Post('/clear_local/:db')
+  async clearLocal(@Param('db') db: string): Promise<any> {
+    await this.adminService.clearLocal(db);
+    return true;
+  }
+}

src/admin/admin.module.ts

@@ -1,11 +1,13 @@
 import { Module } from '@nestjs/common';
-import { AdminController } from './admin/admin.controller';
+import { AdminController } from './admin.controller';
 import { PermissionModule } from '../permissions/permission.module';
 import { CouchdbModule } from '../couchdb/couchdb.module';
 import { AuthModule } from '../auth/auth.module';
+import { AdminService } from './admin.service';
 
 @Module({
   controllers: [AdminController],
   imports: [PermissionModule, CouchdbModule, AuthModule],
+  providers: [AdminService],
 })
 export class AdminModule {}

src/admin/admin/admin.controller.spec.ts → src/admin/admin.service.spec.ts

@@ -1,11 +1,10 @@
 import { Test, TestingModule } from '@nestjs/testing';
-import { AdminController } from './admin.controller';
+import { AdminService } from './admin.service';
+import { CouchdbService } from '../couchdb/couchdb.service';
 import { of } from 'rxjs';
-import { CouchdbService } from '../../couchdb/couchdb.service';
-import { authGuardMockProviders } from '../../auth/auth-guard-mock.providers';
 
-describe('AdminController', () => {
-  let controller: AdminController;
+describe('AdminService', () => {
+  let service: AdminService;
   let mockCouchDBService: CouchdbService;
 
   beforeEach(async () => {
@@ -14,18 +13,17 @@ describe('AdminController', () => {
       delete: () => of({}),
     } as any;
     const module: TestingModule = await Test.createTestingModule({
-      controllers: [AdminController],
       providers: [
-        ...authGuardMockProviders,
+        AdminService,
         { provide: CouchdbService, useValue: mockCouchDBService },
       ],
     }).compile();
 
-    controller = module.get(AdminController);
+    service = module.get<AdminService>(AdminService);
   });
 
   it('should be defined', () => {
-    expect(controller).toBeDefined();
+    expect(service).toBeDefined();
   });
 
   it('should delete all docs in the _local db', async () => {
@@ -42,12 +40,11 @@ describe('AdminController', () => {
     jest.spyOn(mockCouchDBService, 'delete').mockReturnValue(of(undefined));
     const dbName = 'app';
 
-    const result = await controller.clearLocal(dbName);
+    await service.clearLocal(dbName);
 
     expect(mockCouchDBService.get).toHaveBeenCalledWith(dbName, '_local_docs');
     mockAllDocsResponse.rows.forEach((row) => {
       expect(mockCouchDBService.delete).toHaveBeenCalledWith(dbName, row.id);
     });
-    expect(result).toBe(true);
   });
 });

src/admin/admin.service.ts

@@ -0,0 +1,27 @@
+import { Injectable } from '@nestjs/common';
+import { firstValueFrom } from 'rxjs';
+import { AllDocsResponse } from '../restricted-endpoints/replication/bulk-document/couchdb-dtos/all-docs.dto';
+import { CouchdbService } from '../couchdb/couchdb.service';
+
+@Injectable()
+export class AdminService {
+  constructor(private couchdbService: CouchdbService) {}
+
+  async clearLocal(db: string) {
+    const localDocsResponse = await firstValueFrom(
+      this.couchdbService.get<AllDocsResponse>(db, '_local_docs'),
+    );
+
+    // Get IDs of the replication checkpoints
+    const ids = localDocsResponse.rows
+      .map((doc) => doc.id)
+      .filter(
+        (id) => !id.includes('purge-mrview') && !id.includes('shard-sync'),
+      );
+    const deletePromises = ids.map((id) =>
+      firstValueFrom(this.couchdbService.delete(db, id)),
+    );
+
+    await Promise.all(deletePromises);
+  }
+}

src/permissions/rules/rules.service.spec.ts

@@ -6,14 +6,18 @@ import { Permission } from './permission';
 import { ConfigService } from '@nestjs/config';
 import { CouchdbService } from '../../couchdb/couchdb.service';
 import { ChangesResponse } from '../../restricted-endpoints/replication/bulk-document/couchdb-dtos/changes.dto';
+import { AdminService } from '../../admin/admin.service';
 
 describe('RulesService', () => {
   let service: RulesService;
   let adminRules: DocumentRule[];
   let userRules: DocumentRule[];
   let mockCouchDBService: CouchdbService;
+  let mockAdminService: AdminService;
+
   let testPermission: Permission;
   let changesResponse: ChangesResponse;
+
   const normalUser = new UserInfo('normalUser', ['user_app']);
   const adminUser = new UserInfo('superUser', ['user_app', 'admin_app']);
   const DATABASE_NAME = 'app';
@@ -28,6 +32,7 @@ describe('RulesService', () => {
     });
     userRules = testPermission.data[normalUser.roles[0]];
     adminRules = testPermission.data[adminUser.roles[1]];
+
     changesResponse = {
       last_seq: 'initial_seq',
       results: [
@@ -43,6 +48,10 @@ describe('RulesService', () => {
       .mockReturnValueOnce(of(changesResponse))
       .mockReturnValueOnce(NEVER);
 
+    mockAdminService = {
+      clearLocal: jest.fn().mockResolvedValue(undefined),
+    } as any;
+
     const module = await Test.createTestingModule({
       providers: [
         RulesService,
@@ -53,6 +62,7 @@ describe('RulesService', () => {
           }),
         },
         { provide: CouchdbService, useValue: mockCouchDBService },
+        { provide: AdminService, useValue: mockAdminService },
       ],
     }).compile();
 
@@ -178,4 +188,40 @@ describe('RulesService', () => {
     expect(result).toEqual([publicRule]);
     expect(result).not.toContain(testPermission.data.default);
   });
+
+  it('should update rules and call clear_local when permission doc changed', () => {
+    jest.useFakeTimers();
+
+    const updatedPermission = new Permission({
+      user_app: [{ action: 'manage', subject: 'all' }],
+    });
+    const updatedPermissionChange = {
+      last_seq: '1',
+      results: [
+        {
+          doc: updatedPermission,
+          seq: '1',
+          changes: [],
+          id: updatedPermission._id,
+        },
+      ],
+      pending: 0,
+    };
+
+    jest
+      .spyOn(mockCouchDBService, 'get')
+      .mockReturnValueOnce(of(changesResponse))
+      .mockReturnValueOnce(of(updatedPermissionChange))
+      .mockReturnValue(NEVER);
+
+    service.loadRulesContinuously('app');
+    jest.advanceTimersByTime(1500);
+
+    expect(service.getRulesForUser(normalUser)).toEqual([
+      { action: 'manage', subject: 'all' },
+    ]);
+    expect(mockAdminService.clearLocal).toHaveBeenCalled();
+
+    jest.useRealTimers();
+  });
 });

src/permissions/rules/rules.service.ts

@@ -8,6 +8,7 @@ import { CouchdbService } from '../../couchdb/couchdb.service';
 import { ConfigService } from '@nestjs/config';
 import { ChangesResponse } from '../../restricted-endpoints/replication/bulk-document/couchdb-dtos/changes.dto';
 import { get } from 'lodash';
+import { AdminService } from '../../admin/admin.service';
 
 export type DocumentRule = RawRuleOf<DocumentAbility>;
 
@@ -24,6 +25,7 @@ export class RulesService {
   constructor(
     private couchdbService: CouchdbService,
     private configService: ConfigService,
+    private adminService: AdminService,
   ) {
     const permissionDbName = this.configService.get(
       RulesService.ENV_PERMISSION_DB,
@@ -60,8 +62,16 @@ export class RulesService {
       )
       .subscribe((changes) => {
         this.lastSeq = changes.last_seq;
-        if (changes.results.length > 0) {
-          this.permission = changes.results[0].doc.data;
+        if (changes.results?.length > 0) {
+          const newPermissions = changes.results[0].doc.data;
+          this.permission = newPermissions;
+
+          if (
+            this.permission !== undefined && // do not clear upon restart of the API
+            JSON.stringify(this.permission) !== JSON.stringify(newPermissions)
+          ) {
+            this.adminService.clearLocal(db);
+          }
         }
       });
   }