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@firebase/firestore

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The Cloud Firestore component of the Firebase JS SDK.

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/** * @license * Copyright 2020 Google LLC * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import { ChangeType, ViewSnapshot } from '../core/view_snapshot'; import { FieldPath } from '../lite-api/field_path'; import { DocumentData, PartialWithFieldValue, Query, SetOptions, WithFieldValue } from '../lite-api/reference'; import { DocumentSnapshot as LiteDocumentSnapshot, FirestoreDataConverter as LiteFirestoreDataConverter } from '../lite-api/snapshot'; import { UntypedFirestoreDataConverter } from '../lite-api/user_data_reader'; import { AbstractUserDataWriter } from '../lite-api/user_data_writer'; import { Document } from '../model/document'; import { DocumentKey } from '../model/document_key'; import { Firestore } from './database'; import { SnapshotListenOptions } from './reference_impl'; /** * Converter used by `withConverter()` to transform user objects of type * `AppModelType` into Firestore data of type `DbModelType`. * * Using the converter allows you to specify generic type arguments when * storing and retrieving objects from Firestore. * * In this context, an "AppModel" is a class that is used in an application to * package together related information and functionality. Such a class could, * for example, have properties with complex, nested data types, properties used * for memoization, properties of types not supported by Firestore (such as * `symbol` and `bigint`), and helper functions that perform compound * operations. Such classes are not suitable and/or possible to store into a * Firestore database. Instead, instances of such classes need to be converted * to "plain old JavaScript objects" (POJOs) with exclusively primitive * properties, potentially nested inside other POJOs or arrays of POJOs. In this * context, this type is referred to as the "DbModel" and would be an object * suitable for persisting into Firestore. For convenience, applications can * implement `FirestoreDataConverter` and register the converter with Firestore * objects, such as `DocumentReference` or `Query`, to automatically convert * `AppModel` to `DbModel` when storing into Firestore, and convert `DbModel` * to `AppModel` when retrieving from Firestore. * * @example * * Simple Example * * ```typescript * const numberConverter = { * toFirestore(value: WithFieldValue<number>) { * return { value }; * }, * fromFirestore(snapshot: QueryDocumentSnapshot, options: SnapshotOptions) { * return snapshot.data(options).value as number; * } * }; * * async function simpleDemo(db: Firestore): Promise<void> { * const documentRef = doc(db, 'values/value123').withConverter(numberConverter); * * // converters are used with `setDoc`, `addDoc`, and `getDoc` * await setDoc(documentRef, 42); * const snapshot1 = await getDoc(documentRef); * assertEqual(snapshot1.data(), 42); * * // converters are not used when writing data with `updateDoc` * await updateDoc(documentRef, { value: 999 }); * const snapshot2 = await getDoc(documentRef); * assertEqual(snapshot2.data(), 999); * } * ``` * * Advanced Example * * ```typescript * // The Post class is a model that is used by our application. * // This class may have properties and methods that are specific * // to our application execution, which do not need to be persisted * // to Firestore. * class Post { * constructor( * readonly title: string, * readonly author: string, * readonly lastUpdatedMillis: number * ) {} * toString(): string { * return `${this.title} by ${this.author}`; * } * } * * // The PostDbModel represents how we want our posts to be stored * // in Firestore. This DbModel has different properties (`ttl`, * // `aut`, and `lut`) from the Post class we use in our application. * interface PostDbModel { * ttl: string; * aut: { firstName: string; lastName: string }; * lut: Timestamp; * } * * // The `PostConverter` implements `FirestoreDataConverter` and specifies * // how the Firestore SDK can convert `Post` objects to `PostDbModel` * // objects and vice versa. * class PostConverter implements FirestoreDataConverter<Post, PostDbModel> { * toFirestore(post: WithFieldValue<Post>): WithFieldValue<PostDbModel> { * return { * ttl: post.title, * aut: this._autFromAuthor(post.author), * lut: this._lutFromLastUpdatedMillis(post.lastUpdatedMillis) * }; * } * * fromFirestore(snapshot: QueryDocumentSnapshot, options: SnapshotOptions): Post { * const data = snapshot.data(options) as PostDbModel; * const author = `${data.aut.firstName} ${data.aut.lastName}`; * return new Post(data.ttl, author, data.lut.toMillis()); * } * * _autFromAuthor( * author: string | FieldValue * ): { firstName: string; lastName: string } | FieldValue { * if (typeof author !== 'string') { * // `author` is a FieldValue, so just return it. * return author; * } * const [firstName, lastName] = author.split(' '); * return {firstName, lastName}; * } * * _lutFromLastUpdatedMillis( * lastUpdatedMillis: number | FieldValue * ): Timestamp | FieldValue { * if (typeof lastUpdatedMillis !== 'number') { * // `lastUpdatedMillis` must be a FieldValue, so just return it. * return lastUpdatedMillis; * } * return Timestamp.fromMillis(lastUpdatedMillis); * } * } * * async function advancedDemo(db: Firestore): Promise<void> { * // Create a `DocumentReference` with a `FirestoreDataConverter`. * const documentRef = doc(db, 'posts/post123').withConverter(new PostConverter()); * * // The `data` argument specified to `setDoc()` is type checked by the * // TypeScript compiler to be compatible with `Post`. Since the `data` * // argument is typed as `WithFieldValue<Post>` rather than just `Post`, * // this allows properties of the `data` argument to also be special * // Firestore values that perform server-side mutations, such as * // `arrayRemove()`, `deleteField()`, and `serverTimestamp()`. * await setDoc(documentRef, { * title: 'My Life', * author: 'Foo Bar', * lastUpdatedMillis: serverTimestamp() * }); * * // The TypeScript compiler will fail to compile if the `data` argument to * // `setDoc()` is _not_ compatible with `WithFieldValue<Post>`. This * // type checking prevents the caller from specifying objects with incorrect * // properties or property values. * // @ts-expect-error "Argument of type { ttl: string; } is not assignable * // to parameter of type WithFieldValue<Post>" * await setDoc(documentRef, { ttl: 'The Title' }); * * // When retrieving a document with `getDoc()` the `DocumentSnapshot` * // object's `data()` method returns a `Post`, rather than a generic object, * // which would have been returned if the `DocumentReference` did _not_ have a * // `FirestoreDataConverter` attached to it. * const snapshot1: DocumentSnapshot<Post> = await getDoc(documentRef); * const post1: Post = snapshot1.data()!; * if (post1) { * assertEqual(post1.title, 'My Life'); * assertEqual(post1.author, 'Foo Bar'); * } * * // The `data` argument specified to `updateDoc()` is type checked by the * // TypeScript compiler to be compatible with `PostDbModel`. Note that * // unlike `setDoc()`, whose `data` argument must be compatible with `Post`, * // the `data` argument to `updateDoc()` must be compatible with * // `PostDbModel`. Similar to `setDoc()`, since the `data` argument is typed * // as `WithFieldValue<PostDbModel>` rather than just `PostDbModel`, this * // allows properties of the `data` argument to also be those special * // Firestore values, like `arrayRemove()`, `deleteField()`, and * // `serverTimestamp()`. * await updateDoc(documentRef, { * 'aut.firstName': 'NewFirstName', * lut: serverTimestamp() * }); * * // The TypeScript compiler will fail to compile if the `data` argument to * // `updateDoc()` is _not_ compatible with `WithFieldValue<PostDbModel>`. * // This type checking prevents the caller from specifying objects with * // incorrect properties or property values. * // @ts-expect-error "Argument of type { title: string; } is not assignable * // to parameter of type WithFieldValue<PostDbModel>" * await updateDoc(documentRef, { title: 'New Title' }); * const snapshot2: DocumentSnapshot<Post> = await getDoc(documentRef); * const post2: Post = snapshot2.data()!; * if (post2) { * assertEqual(post2.title, 'My Life'); * assertEqual(post2.author, 'NewFirstName Bar'); * } * } * ``` */ export interface FirestoreDataConverter<AppModelType, DbModelType extends DocumentData = DocumentData> extends LiteFirestoreDataConverter<AppModelType, DbModelType> { /** * Called by the Firestore SDK to convert a custom model object of type * `AppModelType` into a plain JavaScript object (suitable for writing * directly to the Firestore database) of type `DbModelType`. To use `set()` * with `merge` and `mergeFields`, `toFirestore()` must be defined with * `PartialWithFieldValue<AppModelType>`. * * The `WithFieldValue<T>` type extends `T` to also allow FieldValues such as * {@link (deleteField:1)} to be used as property values. */ toFirestore(modelObject: WithFieldValue<AppModelType>): WithFieldValue<DbModelType>; /** * Called by the Firestore SDK to convert a custom model object of type * `AppModelType` into a plain JavaScript object (suitable for writing * directly to the Firestore database) of type `DbModelType`. Used with * {@link (setDoc:1)}, {@link (WriteBatch.set:1)} and * {@link (Transaction.set:1)} with `merge:true` or `mergeFields`. * * The `PartialWithFieldValue<T>` type extends `Partial<T>` to allow * FieldValues such as {@link (arrayUnion:1)} to be used as property values. * It also supports nested `Partial` by allowing nested fields to be * omitted. */ toFirestore(modelObject: PartialWithFieldValue<AppModelType>, options: SetOptions): PartialWithFieldValue<DbModelType>; /** * Called by the Firestore SDK to convert Firestore data into an object of * type `AppModelType`. You can access your data by calling: * `snapshot.data(options)`. * * Generally, the data returned from `snapshot.data()` can be cast to * `DbModelType`; however, this is not guaranteed because Firestore does not * enforce a schema on the database. For example, writes from a previous * version of the application or writes from another client that did not use a * type converter could have written data with different properties and/or * property types. The implementation will need to choose whether to * gracefully recover from non-conforming data or throw an error. * * To override this method, see {@link (FirestoreDataConverter.fromFirestore:1)}. * * @param snapshot - A `QueryDocumentSnapshot` containing your data and metadata. * @param options - The `SnapshotOptions` from the initial call to `data()`. */ fromFirestore(snapshot: QueryDocumentSnapshot<DocumentData, DocumentData>, options?: SnapshotOptions): AppModelType; } /** * Options that configure how data is retrieved from a `DocumentSnapshot` (for * example the desired behavior for server timestamps that have not yet been set * to their final value). */ export interface SnapshotOptions { /** * If set, controls the return value for server timestamps that have not yet * been set to their final value. * * By specifying 'estimate', pending server timestamps return an estimate * based on the local clock. This estimate will differ from the final value * and cause these values to change once the server result becomes available. * * By specifying 'previous', pending timestamps will be ignored and return * their previous value instead. * * If omitted or set to 'none', `null` will be returned by default until the * server value becomes available. */ readonly serverTimestamps?: 'estimate' | 'previous' | 'none'; } /** * Metadata about a snapshot, describing the state of the snapshot. */ export declare class SnapshotMetadata { /** * True if the snapshot contains the result of local writes (for example * `set()` or `update()` calls) that have not yet been committed to the * backend. If your listener has opted into metadata updates (via * `SnapshotListenOptions`) you will receive another snapshot with * `hasPendingWrites` equal to false once the writes have been committed to * the backend. */ readonly hasPendingWrites: boolean; /** * True if the snapshot was created from cached data rather than guaranteed * up-to-date server data. If your listener has opted into metadata updates * (via `SnapshotListenOptions`) you will receive another snapshot with * `fromCache` set to false once the client has received up-to-date data from * the backend. */ readonly fromCache: boolean; /** @hideconstructor */ constructor(hasPendingWrites: boolean, fromCache: boolean); /** * Returns true if this `SnapshotMetadata` is equal to the provided one. * * @param other - The `SnapshotMetadata` to compare against. * @returns true if this `SnapshotMetadata` is equal to the provided one. */ isEqual(other: SnapshotMetadata): boolean; } /** * The type of a `DocumentChange` may be 'added', 'removed', or 'modified'. */ export type DocumentChangeType = 'added' | 'removed' | 'modified'; /** * A `DocumentChange` represents a change to the documents matching a query. * It contains the document affected and the type of change that occurred. */ export interface DocumentChange<AppModelType = DocumentData, DbModelType extends DocumentData = DocumentData> { /** The type of change ('added', 'modified', or 'removed'). */ readonly type: DocumentChangeType; /** The document affected by this change. */ readonly doc: QueryDocumentSnapshot<AppModelType, DbModelType>; /** * The index of the changed document in the result set immediately prior to * this `DocumentChange` (i.e. supposing that all prior `DocumentChange` objects * have been applied). Is `-1` for 'added' events. */ readonly oldIndex: number; /** * The index of the changed document in the result set immediately after * this `DocumentChange` (i.e. supposing that all prior `DocumentChange` * objects and the current `DocumentChange` object have been applied). * Is -1 for 'removed' events. */ readonly newIndex: number; } /** * A `DocumentSnapshot` contains data read from a document in your Firestore * database. The data can be extracted with `.data()` or `.get(<field>)` to * get a specific field. * * For a `DocumentSnapshot` that points to a non-existing document, any data * access will return 'undefined'. You can use the `exists()` method to * explicitly verify a document's existence. */ export declare class DocumentSnapshot<AppModelType = DocumentData, DbModelType extends DocumentData = DocumentData> extends LiteDocumentSnapshot<AppModelType, DbModelType> { readonly _firestore: Firestore; private readonly _firestoreImpl; /** * Metadata about the `DocumentSnapshot`, including information about its * source and local modifications. */ readonly metadata: SnapshotMetadata; /** @hideconstructor protected */ constructor(_firestore: Firestore, userDataWriter: AbstractUserDataWriter, key: DocumentKey, document: Document | null, metadata: SnapshotMetadata, converter: UntypedFirestoreDataConverter<AppModelType, DbModelType> | null); /** * Returns whether or not the data exists. True if the document exists. */ exists(): this is QueryDocumentSnapshot<AppModelType, DbModelType>; /** * Retrieves all fields in the document as an `Object`. Returns `undefined` if * the document doesn't exist. * * By default, `serverTimestamp()` values that have not yet been * set to their final value will be returned as `null`. You can override * this by passing an options object. * * @param options - An options object to configure how data is retrieved from * the snapshot (for example the desired behavior for server timestamps that * have not yet been set to their final value). * @returns An `Object` containing all fields in the document or `undefined` if * the document doesn't exist. */ data(options?: SnapshotOptions): AppModelType | undefined; /** * Retrieves the field specified by `fieldPath`. Returns `undefined` if the * document or field doesn't exist. * * By default, a `serverTimestamp()` that has not yet been set to * its final value will be returned as `null`. You can override this by * passing an options object. * * @param fieldPath - The path (for example 'foo' or 'foo.bar') to a specific * field. * @param options - An options object to configure how the field is retrieved * from the snapshot (for example the desired behavior for server timestamps * that have not yet been set to their final value). * @returns The data at the specified field location or undefined if no such * field exists in the document. */ get(fieldPath: string | FieldPath, options?: SnapshotOptions): any; } /** * A `QueryDocumentSnapshot` contains data read from a document in your * Firestore database as part of a query. The document is guaranteed to exist * and its data can be extracted with `.data()` or `.get(<field>)` to get a * specific field. * * A `QueryDocumentSnapshot` offers the same API surface as a * `DocumentSnapshot`. Since query results contain only existing documents, the * `exists` property will always be true and `data()` will never return * 'undefined'. */ export declare class QueryDocumentSnapshot<AppModelType = DocumentData, DbModelType extends DocumentData = DocumentData> extends DocumentSnapshot<AppModelType, DbModelType> { /** * Retrieves all fields in the document as an `Object`. * * By default, `serverTimestamp()` values that have not yet been * set to their final value will be returned as `null`. You can override * this by passing an options object. * * @override * @param options - An options object to configure how data is retrieved from * the snapshot (for example the desired behavior for server timestamps that * have not yet been set to their final value). * @returns An `Object` containing all fields in the document. */ data(options?: SnapshotOptions): AppModelType; } /** * A `QuerySnapshot` contains zero or more `DocumentSnapshot` objects * representing the results of a query. The documents can be accessed as an * array via the `docs` property or enumerated using the `forEach` method. The * number of documents can be determined via the `empty` and `size` * properties. */ export declare class QuerySnapshot<AppModelType = DocumentData, DbModelType extends DocumentData = DocumentData> { readonly _firestore: Firestore; readonly _userDataWriter: AbstractUserDataWriter; readonly _snapshot: ViewSnapshot; /** * Metadata about this snapshot, concerning its source and if it has local * modifications. */ readonly metadata: SnapshotMetadata; /** * The query on which you called `get` or `onSnapshot` in order to get this * `QuerySnapshot`. */ readonly query: Query<AppModelType, DbModelType>; private _cachedChanges?; private _cachedChangesIncludeMetadataChanges?; /** @hideconstructor */ constructor(_firestore: Firestore, _userDataWriter: AbstractUserDataWriter, query: Query<AppModelType, DbModelType>, _snapshot: ViewSnapshot); /** An array of all the documents in the `QuerySnapshot`. */ get docs(): Array<QueryDocumentSnapshot<AppModelType, DbModelType>>; /** The number of documents in the `QuerySnapshot`. */ get size(): number; /** True if there are no documents in the `QuerySnapshot`. */ get empty(): boolean; /** * Enumerates all of the documents in the `QuerySnapshot`. * * @param callback - A callback to be called with a `QueryDocumentSnapshot` for * each document in the snapshot. * @param thisArg - The `this` binding for the callback. */ forEach(callback: (result: QueryDocumentSnapshot<AppModelType, DbModelType>) => void, thisArg?: unknown): void; /** * Returns an array of the documents changes since the last snapshot. If this * is the first snapshot, all documents will be in the list as 'added' * changes. * * @param options - `SnapshotListenOptions` that control whether metadata-only * changes (i.e. only `DocumentSnapshot.metadata` changed) should trigger * snapshot events. */ docChanges(options?: SnapshotListenOptions): Array<DocumentChange<AppModelType, DbModelType>>; } /** Calculates the array of `DocumentChange`s for a given `ViewSnapshot`. */ export declare function changesFromSnapshot<AppModelType, DbModelType extends DocumentData>(querySnapshot: QuerySnapshot<AppModelType, DbModelType>, includeMetadataChanges: boolean): Array<DocumentChange<AppModelType, DbModelType>>; export declare function resultChangeType(type: ChangeType): DocumentChangeType; /** * Returns true if the provided snapshots are equal. * * @param left - A snapshot to compare. * @param right - A snapshot to compare. * @returns true if the snapshots are equal. */ export declare function snapshotEqual<AppModelType, DbModelType extends DocumentData>(left: DocumentSnapshot<AppModelType, DbModelType> | QuerySnapshot<AppModelType, DbModelType>, right: DocumentSnapshot<AppModelType, DbModelType> | QuerySnapshot<AppModelType, DbModelType>): boolean;