BO42 - Create utility to query Firestore with pagination

functions/src/utilities/firestore/get-paginated.ts

@@ -0,0 +1,73 @@
+import {
+  DocumentData,
+  FirestoreDataConverter,
+  getFirestore,
+  Query,
+} from "firebase-admin/firestore";
+import {
+  OrderDirection,
+  PaginatedResponse,
+  PaginationParams,
+} from "../../api/http/pagination/pagination.type";
+
+const orderBy = <M, D extends DocumentData>(
+  query: Query<M, D>,
+  orderBy: string,
+  orderDirection: OrderDirection,
+): Query<M, D> => {
+  if (!orderBy) return query;
+  return query.orderBy(orderBy, orderDirection);
+};
+
+const addPageFilters = <M, D extends DocumentData>(
+  query: Query<M, D>,
+  params: PaginationParams,
+): Query<M, D> => {
+  if (params.offset > 0) {
+    query = query.offset(params.offset);
+  }
+
+  return query.limit(params.limit);
+};
+
+const getPaginated = async <M, D extends DocumentData>(
+  collection: string,
+  converter: FirestoreDataConverter<M, D>,
+  params: PaginationParams,
+): Promise<PaginatedResponse<M>> => {
+  try {
+    let query: Query<M, D> = getFirestore()
+      .collection(collection)
+      .withConverter<M, D>(converter);
+    query = orderBy(query, params.orderBy, params.orderDirection);
+
+    const count = (await query.count().get()).data().count;
+    const totalPages = Math.ceil(count / params.limit);
+    if (count === 0) {
+      return {
+        data: [],
+        total: 0,
+        limit: params.limit,
+        offset: params.offset,
+        totalPages: 0,
+      };
+    }
+
+    query = addPageFilters(query, params);
+
+    const result = await query.get();
+    const items = result.docs.map((doc) => doc.data());
+    return {
+      data: items,
+      total: count,
+      limit: params.limit,
+      offset: params.offset,
+      totalPages,
+    };
+  } catch (error) {
+    console.error(`Error getting documents from ${collection}`, error);
+    throw error;
+  }
+};
+
+export default getPaginated;

functions/src/utilities/firestore/model-document-mapper.ts

@@ -0,0 +1,11 @@
+import { Timestamp } from "firebase-admin/firestore";
+
+type MapDateToTimestamp<PropType> = PropType extends Date
+  ? Timestamp
+  : PropType;
+
+type FirestoreDocument<T> = {
+  [PropertyKey in keyof T]: MapDateToTimestamp<T[PropertyKey]>;
+};
+
+export default FirestoreDocument;

functions/test/utilities/firestore/get-paginated.test.ts

@@ -0,0 +1,231 @@
+import { afterEach, before, beforeEach, describe, test } from "mocha";
+import { initializeFirebaseApp } from "../../../src/config";
+import {
+  FirestoreDataConverter,
+  getFirestore,
+  Timestamp,
+} from "firebase-admin/firestore";
+// eslint-disable-next-line max-len
+import { PaginationParams } from "../../../src/api/http/pagination/pagination.type";
+import getPaginated from "../../../src/utilities/firestore/get-paginated";
+// eslint-disable-next-line max-len
+import FirestoreDocument from "../../../src/utilities/firestore/model-document-mapper";
+import { expect } from "chai";
+
+type TestModel = {
+  id?: string;
+  lastUpdate: Date;
+  name: string;
+  userUpdate: {
+    id: string;
+    username: string;
+    name: string;
+    role: string;
+  };
+  deleted: boolean;
+};
+
+type TestDoc = FirestoreDocument<TestModel>;
+
+describe("Get all documents", () => {
+  const testCollection = "test-collection";
+  const testConverter: FirestoreDataConverter<TestModel, TestDoc> = {
+    toFirestore: (model: TestModel): TestDoc => {
+      return {
+        ...model,
+        lastUpdate: Timestamp.fromDate(model.lastUpdate),
+      };
+    },
+    fromFirestore: (
+      snapshot: FirebaseFirestore.QueryDocumentSnapshot,
+    ): TestModel => {
+      const data = snapshot.data();
+      return {
+        id: snapshot.id,
+        ...data,
+        lastUpdate: data.lastUpdate.toDate(),
+      } as TestModel;
+    },
+  };
+  const modelsToSave: TestModel[] = [
+    {
+      id: "test-model-1",
+      lastUpdate: new Date("2024-01-01"),
+      name: "name-1",
+      userUpdate: {
+        id: "test-id-1",
+        username: "test",
+        name: "Test User",
+        role: "admin",
+      },
+      deleted: false,
+    },
+    {
+      id: "test-model-2",
+      lastUpdate: new Date("2024-01-02"),
+      name: "name-2",
+      userUpdate: {
+        id: "test-id-1",
+        username: "test",
+        name: "Test User",
+        role: "admin",
+      },
+      deleted: false,
+    },
+    {
+      id: "test-model-3",
+      lastUpdate: new Date("2024-01-03"),
+      name: "name-3",
+      userUpdate: {
+        id: "test-id-2",
+        username: "test",
+        name: "Test User",
+        role: "admin",
+      },
+      deleted: false,
+    },
+    {
+      id: "test-model-4",
+      lastUpdate: new Date("2024-01-04"),
+      name: "name-4",
+      userUpdate: {
+        id: "test-id-2",
+        username: "test",
+        name: "Test User",
+        role: "admin",
+      },
+      deleted: false,
+    },
+    {
+      id: "test-model-5",
+      lastUpdate: new Date("2024-01-05"),
+      name: "name-5",
+      userUpdate: {
+        id: "test-id-3",
+        username: "test",
+        name: "Test User",
+        role: "admin",
+      },
+      deleted: false,
+    },
+    {
+      id: "test-model-6",
+      lastUpdate: new Date("2024-01-06"),
+      name: "name-6",
+      userUpdate: {
+        id: "test-id-3",
+        username: "test",
+        name: "Test User",
+        role: "admin",
+      },
+      deleted: false,
+    },
+    {
+      id: "test-model-7",
+      lastUpdate: new Date("2024-01-07"),
+      name: "name-7",
+      userUpdate: {
+        id: "test-id-3",
+        username: "test",
+        name: "Test User",
+        role: "admin",
+      },
+      deleted: false,
+    },
+    {
+      id: "test-model-8",
+      lastUpdate: new Date("2024-01-08"),
+      name: "name-8",
+      userUpdate: {
+        id: "test-id-4",
+        username: "test",
+        name: "Test User",
+        role: "admin",
+      },
+      deleted: false,
+    },
+  ];
+
+  before(() => {
+    initializeFirebaseApp();
+  });
+
+  beforeEach(async () => {
+    const batch = getFirestore().batch();
+    modelsToSave.forEach((model) => {
+      batch.create(
+        getFirestore().collection(testCollection).doc(model.id!),
+        model,
+      );
+    });
+    await batch.commit();
+  });
+
+  afterEach(async () => {
+    const docs = await getFirestore()
+      .collection(testCollection)
+      .listDocuments();
+    const batch = getFirestore().batch();
+    docs.forEach((doc) => {
+      batch.delete(doc);
+    });
+    await batch.commit();
+  });
+
+  test("Should get first page ordered", async () => {
+    const params: PaginationParams = {
+      offset: 0,
+      limit: 2,
+      orderBy: "lastUpdate",
+      orderDirection: "desc",
+    };
+
+    const result = await getPaginated(testCollection, testConverter, params);
+
+    expect(result).deep.equal({
+      data: [modelsToSave[7], modelsToSave[6]],
+      total: modelsToSave.length,
+      limit: 2,
+      offset: 0,
+      totalPages: Math.ceil(modelsToSave.length / params.limit),
+    });
+  });
+
+  test("should get second page ordered", async () => {
+    const params: PaginationParams = {
+      offset: 2,
+      limit: 2,
+      orderBy: "lastUpdate",
+      orderDirection: "desc",
+    };
+
+    const result = await getPaginated(testCollection, testConverter, params);
+
+    expect(result).deep.equal({
+      data: [modelsToSave[5], modelsToSave[4]],
+      total: modelsToSave.length,
+      limit: 2,
+      offset: 2,
+      totalPages: Math.ceil(modelsToSave.length / params.limit),
+    });
+  });
+
+  test("should get last page ordered", async () => {
+    const params: PaginationParams = {
+      offset: 6,
+      limit: 2,
+      orderBy: "lastUpdate",
+      orderDirection: "desc",
+    };
+
+    const result = await getPaginated(testCollection, testConverter, params);
+
+    expect(result).deep.equal({
+      data: [modelsToSave[1], modelsToSave[0]],
+      total: modelsToSave.length,
+      limit: 2,
+      offset: 6,
+      totalPages: Math.ceil(modelsToSave.length / params.limit),
+    });
+  });
+});