handle pagination for ListAuthProvider(Description)s

Author: AlexTugarev

components/server/src/api/auth-provider-service-api.ts

@@ -25,6 +25,7 @@ import {
 import { AuthProviderService } from "../auth/auth-provider-service";
 import { AuthProviderEntry, AuthProviderInfo } from "@gitpod/gitpod-protocol";
 import { Unauthenticated } from "./unauthenticated";
+import { selectPage } from "./pagination";
 
 @injectable()
 export class AuthProviderServiceAPI implements ServiceImpl<typeof AuthProviderServiceInterface> {
@@ -98,10 +99,14 @@ export class AuthProviderServiceAPI implements ServiceImpl<typeof AuthProviderSe
             ? await this.authProviderService.getAuthProvidersOfOrg(context.user.id, organizationId)
             : await this.authProviderService.getAuthProvidersOfUser(context.user.id);
 
-        const redacted = authProviders.map(AuthProviderEntry.redact.bind(AuthProviderEntry));
+        const selectedProviders = selectPage(authProviders, request.pagination);
+        const redacted = selectedProviders.map(AuthProviderEntry.redact.bind(AuthProviderEntry));
 
         const result = new ListAuthProvidersResponse({
             authProviders: redacted.map((ap) => this.apiConverter.toAuthProvider(ap)),
+            pagination: {
+                total: redacted.length,
+            },
         });
         return result;
     }
@@ -111,16 +116,19 @@ export class AuthProviderServiceAPI implements ServiceImpl<typeof AuthProviderSe
      */
     @Unauthenticated()
     async listAuthProviderDescriptions(
-        _request: ListAuthProviderDescriptionsRequest,
+        request: ListAuthProviderDescriptionsRequest,
         context: HandlerContext,
     ): Promise<ListAuthProviderDescriptionsResponse> {
         const user = context.user;
         const aps = user
             ? await this.authProviderService.getAuthProviderDescriptions(user)
             : await this.authProviderService.getAuthProviderDescriptionsUnauthenticated();
 
+        const selectedProviders = selectPage(aps, request.pagination);
         return new ListAuthProviderDescriptionsResponse({
-            descriptions: aps.map((ap: AuthProviderInfo) => this.apiConverter.toAuthProviderDescription(ap)),
+            descriptions: selectedProviders.map((ap: AuthProviderInfo) =>
+                this.apiConverter.toAuthProviderDescription(ap),
+            ),
         });
     }
 

components/server/src/api/pagination.spec.ts

@@ -0,0 +1,39 @@
+/**
+ * Copyright (c) 2023 Gitpod GmbH. All rights reserved.
+ * Licensed under the GNU Affero General Public License (AGPL).
+ * See License.AGPL.txt in the project root for license information.
+ */
+
+import * as chai from "chai";
+import { selectPage, PAGE_DEFAULT, PAGE_SIZE_DEFAULT, PAGE_SIZE_MAX } from "./pagination";
+import { PaginationRequest } from "@gitpod/public-api/lib/gitpod/v1/pagination_pb";
+
+const expect = chai.expect;
+
+describe("selectPage", function () {
+    const a1000 = Array.from({ length: 1000 }, (_, i) => `item${i + 1}`);
+    const a10 = Array.from({ length: 10 }, (_, i) => `item${i + 1}`);
+
+    it(`should return first ${PAGE_SIZE_DEFAULT} if pagination is not specified`, function () {
+        const selection = selectPage(a1000);
+        expect(selection).to.have.lengthOf(PAGE_SIZE_DEFAULT);
+        expect(selection[0]).to.equal(`item${PAGE_DEFAULT}`);
+    });
+    it(`should return first ${PAGE_SIZE_MAX} if page size exceed max`, function () {
+        const selection = selectPage(a1000, new PaginationRequest({ pageSize: PAGE_SIZE_MAX + 1 }));
+        expect(selection).to.have.lengthOf(PAGE_SIZE_MAX);
+        expect(selection[0]).to.equal(`item${PAGE_DEFAULT}`);
+    });
+    it(`should return second page`, function () {
+        const selection = selectPage(a1000, new PaginationRequest({ page: 2, pageSize: 50 }));
+        expect(selection).to.have.lengthOf(50);
+        expect(selection[0]).to.equal(`item${1 * 50 + 1}`);
+        expect(selection[selection.length - 1]).to.equal(`item${2 * 50}`);
+    });
+    it(`should return all if it fits into a page`, function () {
+        const selection = selectPage(a10, new PaginationRequest({ pageSize: 50 }));
+        expect(selection).to.have.lengthOf(10);
+        expect(selection[0]).to.equal(`item${1}`);
+        expect(selection[selection.length - 1]).to.equal(`item${10}`);
+    });
+});

components/server/src/api/pagination.ts

@@ -0,0 +1,18 @@
+/**
+ * Copyright (c) 2023 Gitpod GmbH. All rights reserved.
+ * Licensed under the GNU Affero General Public License (AGPL).
+ * See License.AGPL.txt in the project root for license information.
+ */
+
+import { PaginationRequest } from "@gitpod/public-api/lib/gitpod/v1/pagination_pb";
+
+export const PAGE_SIZE_DEFAULT = 25;
+export const PAGE_SIZE_MAX = 100;
+export const PAGE_DEFAULT = 1;
+
+export function selectPage<T>(all: T[], pagination?: PaginationRequest): T[] {
+    const page = Math.max(pagination?.page || PAGE_DEFAULT, PAGE_DEFAULT);
+    const pageSize = Math.min(pagination?.pageSize || PAGE_SIZE_DEFAULT, PAGE_SIZE_MAX);
+
+    return all.slice(pageSize * (page - 1), pageSize * page);
+}