firestore-dataloader/lib/firestoreDataLoader.js

GraphQL DataLoader for Cloud Firestore.

"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.FirestoreDataLoader = void 0;
const firestore_1 = require("@google-cloud/firestore");
const apollo_datasource_1 = require("apollo-datasource");
const dataloader_1 = __importDefault(require("dataloader"));
const getDocData_1 = require("./utils/getDocData");
/**
 * GraphQL DataLoader for Cloud Firestore.
 */
class FirestoreDataLoader extends apollo_datasource_1.DataSource {
    /**
     * constructor
     * It is assumed to be declared as one of the dataSources.
     * @param baseQuery CollectionReference or Query
     * @param options DataLoader.Options. maxBatchSize is set to 10 due to firestore limitation.
     */
    constructor(baseQuery, options) {
        super();
        this.dataLoader = new dataloader_1.default((keys) => this.loadDataByKeys(baseQuery, keys), {
            ...options,
            // maximum of 10 firestore in clauses.
            maxBatchSize: 10,
        });
    }
    /**
     * load datas by keys
     * @param {CollectionReference | Query} baseQuery CollectionReference or Query
     * @param {string[]} keys
     * @returns documents
     */
    async loadDataByKeys(baseQuery, keys) {
        const snapshot = await baseQuery.where(firestore_1.FieldPath.documentId(), `in`, keys).get();
        if (snapshot.empty)
            return [];
        return keys.map((key) => {
            const doc = snapshot.docs.find((doc) => doc.id === key);
            return doc ? getDocData_1.getDocData(doc) : null;
        });
    }
}
exports.FirestoreDataLoader = FirestoreDataLoader;