### Install and Run Firestore Emulator

Source: https://rnfirebase.io/firestore/emulator

Install the Firebase CLI and start the Firestore emulator. This command will also install the emulator if it's your first time running it.

```bash
curl -sL firebase.tools | bash

firebase emulators:start --only firestore
```

--------------------------------

### Install App Distribution Module

Source: https://rnfirebase.io/app-distribution/usage

Install the core app module and the app-distribution module. For iOS development, ensure you run `pod install` after installation.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the app-distribution module
yarn add @react-native-firebase/app-distribution

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Install React Native Firebase Performance Monitoring

Source: https://rnfirebase.io/perf/usage

Install the app and performance monitoring modules. For iOS, run `pod install` in the `ios` directory.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the performance monitoring module
yarn add @react-native-firebase/perf

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Installation

Source: https://rnfirebase.io/in-app-messaging/usage

Instructions for installing the In-App Messaging module along with its dependencies.

```APIDOC
## Installation

This module requires that the `@react-native-firebase/app` module is already setup and installed. To install the "app" module, view the Getting Started documentation.
This module also requires that the `@react-native-firebase/analytics` module is already setup and installed. To install the "analytics" module, view it's Getting Started documentation.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the in-app-messaging module
yarn add @react-native-firebase/in-app-messaging

# If you're developing your app using iOS, run this command
cd ios/ && pod install
```

Note: in-app-messaging requires a minimum android gradle plugin version of 3.5.4 to compile or you will see `AAPT` errors regarding unexpected XML with `<queries>` elements. However, `react-native@0.63.4` still ships with a default of 3.5.3. If you have not already, you must update the line `classpath("com.android.tools.build:gradle:3.5.3")`in `android/build.gradle` to a minimum of `3.5.4` for android builds to work.
If you're using an older version of React Native without autolinking support, or wish to integrate into an existing project, you can follow the manual installation steps for iOS and Android.
```

--------------------------------

### Install React Native Firebase App and Installations Modules

Source: https://rnfirebase.io/installations/usage

Install the core '@react-native-firebase/app' module first, then add the '@react-native-firebase/installations' module. For iOS development, navigate to the 'ios' directory and run 'pod install'.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the installations module
yarn add @react-native-firebase/installations

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Implement Pagination with Firestore

Source: https://rnfirebase.io/firestore/pagination

This example shows how to fetch data in pages from Firestore. It uses `orderBy` to sort the data, `startAfter` to specify the starting point for the next page, and `limit` to control the page size. The `lastDocument` state variable keeps track of the last document fetched to enable fetching subsequent pages.

```javascript
import React, { useState } from 'react';
import type { Node } from 'react';
import { Text, View, Button, Alert } from 'react-native';

import firestore from '@react-native-firebase/firestore';

const userCollection = firestore().collection('Users');

const App: () => Node = () => {
  const [lastDocument, setLastDocument] = useState();
  const [userData, setUserData] = useState([]);

  function LoadData() {
    console.log('LOAD');
    let query = userCollection.orderBy('age'); // sort the data
    if (lastDocument !== undefined) {
      query = query.startAfter(lastDocument); // fetch data following the last document accessed
    }
    query.limit(3) // limit to your page size, 3 is just an example
        .get()
        .then(querySnapshot => {
          setLastDocument(querySnapshot.docs[querySnapshot.docs.length - 1]);
          MakeUserData(querySnapshot.docs);
        });
    }
  }

  function MakeUserData(docs) {
    let templist = [];
    docs.forEach((doc, i) => {
      console.log(doc._data);
      let temp = (
        <View key={i} style={{ margin: 10 }}>
          <Text>{doc._data.name}</Text>
          <Text>{doc._data.age}</Text>
        </View>
      );
      templist.push(temp);
    });
    setUserData(templist);
  }

  return (
    <View>
      {userData}
      <Button
        onPress={() => {
          LoadData();
        }}
        title="Load Next"
      />
    </View>
  );
};

export default App;

```

--------------------------------

### Install In-App Messaging Module

Source: https://rnfirebase.io/in-app-messaging/usage

Install the necessary modules for In-App Messaging and the core app module. Run `pod install` for iOS projects.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the in-app-messaging module
yarn add @react-native-firebase/in-app-messaging

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Full MFA Sign-in Flow Example

Source: https://rnfirebase.io/auth/multi-factor-auth

A comprehensive example combining initial sign-in, MFA requirement detection, phone verification, and final assertion.

```javascript
import {
  PhoneAuthProvider,
  PhoneMultiFactorGenerator,
  getAuth,
  signInWithEmailAndPassword,
  getMultiFactorResolver,
} from '@react-native-firebase/auth';

signInWithEmailAndPassword(getAuth(), email, password)
  .then(() => {
    // User has not enrolled a second factor
  })
  .catch(error => {
    const { code } = error;
    // Make sure to check if multi factor authentication is required
    if (code === 'auth/multi-factor-auth-required') {
      const resolver = getMultiFactorResolver(error);

      if (resolver.hints.length > 1) {
        // Use resolver.hints to display a list of second factors to the user
      }

      if (resolver.hints[0].factorId === PhoneMultiFactorGenerator.FACTOR_ID) {
        const hint = resolver.hints[0];

        new PhoneAuthProvider(getAuth())
          .verifyPhoneNumber({ multiFactorHint: hint, session: resolver.session }) // triggers the message to the user
          .then(verificationId => setVerificationId(verificationId));

        // Request verificationCode from user

        const credential = PhoneAuthProvider.credential(verificationId, verificationCode);

        const multiFactorAssertion = PhoneMultiFactorGenerator.assertion(credential);

        resolver.resolveSignIn(multiFactorAssertion).then(userCredential => {
          // additionally onAuthStateChanged will be triggered as well
        });
      }
    }
  });

```

--------------------------------

### Setup Custom App Check Provider

Source: https://rnfirebase.io/platforms

Implement a custom App Check provider for 'other' platforms. Ensure your server provides valid tokens and expiration times. This example shows both modular and v8 API configurations.

```typescript
import firebase, { CustomProvider, initializeAppCheck } from '@react-native-firebase/app-check';

const myCustomProvider = new CustomProvider({
  async getToken: () => {
    // TODO: Get the token from your server, e.g. if using a cloud function call the function.
    const tokenFromServer = 'some-token-from-server';
    const expirationFromServer = 1000 * 60 * 60; // 1 hour
    const appCheckToken = {
      token: tokenFromServer,
      expireTimeMillis: expirationFromServer * 1000
    };
    return appCheckToken;
  }
});

// Configure the provider (modular API)
initializeAppCheck(firebaseApp, {
  provider: myCustomProvider
});

// Or configure the provider (v8 API)
firebase.appCheck().initializeAppCheck({ provider: myCustomProvider });

```

--------------------------------

### Setup State for Pagination

Source: https://rnfirebase.io/firestore/pagination

Initializes state variables for tracking the last document and storing fetched user data. This setup is crucial for managing pagination.

```javascript
import React, { useState } from 'react';
import type { Node } from 'react';
import { Text, View, Button, Alert } from 'react-native';

import firestore from '@react-native-firebase/firestore';

const userCollection = firestore().collection('Users');

const App: () => Node = () => {
  const [lastDocument, setLastDocument] = useState();
  const [userData, setUserData] = useState([]);
};
```

--------------------------------

### Install Remote Config Module

Source: https://rnfirebase.io/remote-config/usage

Install the necessary modules for Remote Config, including the core app module. Run `pod install` for iOS projects.

```bash
yarn add @react-native-firebase/app
yarn add @react-native-firebase/remote-config

cd ios/ && pod install
```

--------------------------------

### Install Faker.js for Mock Data

Source: https://rnfirebase.io/functions/writing-deploying-functions

Install the Faker.js library to generate mock data for your Cloud Functions. Run this command in the functions directory.

```bash
cd functions/
npm install @faker-js/faker

```

--------------------------------

### Install Cloud Functions Module

Source: https://rnfirebase.io/functions/usage

Install the Cloud Functions module and its dependency, the app module. Ensure the app module is set up first. For iOS development, run `pod install` after installation.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the functions module
yarn add @react-native-firebase/functions

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Ky HTTP Client with Firebase Performance Hooks

Source: https://rnfirebase.io/perf/ky-integration

This example shows how to create a Ky HTTP client instance that automatically integrates with Firebase Performance Monitoring. It uses `beforeRequest` to start a new metric and `afterResponse` to record response details and stop the metric. Ensure `@react-native-firebase/perf` is installed and configured.

```javascript
import perf from '@react-native-firebase/perf';
import ky from 'ky';

const getContentLength = headers => {
  const length = getHeader('Content-Length', headers);
  return length ? Number(length) : null;
};

const getHeader = (header, headers) => headers.get(header) || headers.get(header.toLowerCase());

const api = ky.create({
  // prevent circular dependency warning
  fetch: fetch,
  hooks: {
    beforeRequest: [
      async (request, options) => {
        const { url, method } = request;
        options.metric = await perf().newHttpMetric(url, method);

        // add any extra metric attributes, if required
        // options.metric.putAttribute('userId', '12345678');
        // options.metric.setRequestPayloadSize(1234)

        await options.metric.start();
      },
    ],

    afterResponse: [
      async (request, options, response) => {
        const { status, headers } = response;
        const { metric } = options;
        metric.setHttpResponseCode(status);
        metric.setResponseContentType(getHeader('Content-Type', headers));
        metric.setResponsePayloadSize(getContentLength(headers));
        await metric.stop();
      },
    ],
  },
});

export default api;
```

--------------------------------

### Creating a Database Reference

Source: https://rnfirebase.io/database/usage

Demonstrates how to get a reference to a specific node in your Realtime Database.

```APIDOC
## Creating a Database Reference

A core concept to understanding Realtime Database are references - a reference to a specific node within your database. A node can be a specific property or sub-nodes.
To create a `Reference`, call the `ref` method:

```javascript
import database from '@react-native-firebase/database';

const reference = database().ref('/users/123');
```

NOTE: To get a reference to a database other than a 'us-central1' default database, you must pass the database URL. You can find your Realtime Database URL in the Realtime Database section of the Firebase console.

```javascript
import { firebase } from '@react-native-firebase/database';

const reference = firebase
  .app()
  .database('https://<databaseName>.<region>.firebasedatabase.app/')
  .ref('/users/123');
```
```

--------------------------------

### Install React Native Firebase App and Storage Modules

Source: https://rnfirebase.io/storage/usage

Install the necessary Firebase modules for your React Native project. Ensure the app module is set up first, then install the storage module. For iOS development, run `pod install`.

```bash
yarn add @react-native-firebase/app
yarn add @react-native-firebase/storage

cd ios/ && pod install
```

--------------------------------

### Install Firebase CLI

Source: https://rnfirebase.io/functions/writing-deploying-functions

Install the Firebase CLI globally on your computer using npm. This tool is essential for building and deploying Cloud Functions.

```bash
npm install -g firebase-tools

```

--------------------------------

### Run iOS App

Source: https://rnfirebase.io/messaging/usage/ios-setup

After completing the setup, rebuild your application to apply the changes. This command is used to run the iOS application.

```bash
npx react-native run-ios

```

--------------------------------

### Install App Check Module

Source: https://rnfirebase.io/app-check/usage/index

Install the `@react-native-firebase/app` and `@react-native-firebase/app-check` modules. For iOS, navigate to the `ios` directory and run `pod install`.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the app-check module
yarn add @react-native-firebase/app-check

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Install the Custom Provider

Source: https://rnfirebase.io/app-check/usage/index

Install the configured custom provider into App Check. Save the returned instance for subsequent usage, such as retrieving tokens.

```typescript
import { getApp } from '@react-native-firebase/app';
import { initializeAppCheck } from '@react-native-firebase/app-check';

const appCheck = await initializeAppCheck(getApp(), {
  provider: rnfbProvider,
  isTokenAutoRefreshEnabled: true,
});

```

--------------------------------

### Install React Native Firebase Auth Module

Source: https://rnfirebase.io/auth/usage

Install the `@react-native-firebase/app` and `@react-native-firebase/auth` modules. For iOS development, run `pod install` in the `ios` directory.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the authentication module
yarn add @react-native-firebase/auth

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Install React Native Firebase App and Database Modules

Source: https://rnfirebase.io/database/usage

Install the core app module and the database module using Yarn. For iOS development, ensure you run `pod install`.

```bash
yarn add @react-native-firebase/app
yarn add @react-native-firebase/database

cd ios/ && pod install && cd ..
```

--------------------------------

### Create a Database Reference

Source: https://rnfirebase.io/database/usage

Get a reference to a specific node in your Realtime Database. The default reference points to '/users/123'.

```javascript
import database from '@react-native-firebase/database';

const reference = database().ref('/users/123');
```

--------------------------------

### Install Firebase Auth Package

Source: https://rnfirebase.io/migrating-to-v6

Install the 'auth' NPM package if your app uses the Authentication module. This is required for v6.

```bash
yarn add @react-native-firebase/auth

```

--------------------------------

### Install Cloud Firestore Module

Source: https://rnfirebase.io/firestore/usage

Install the Cloud Firestore module using Yarn. Ensure the `@react-native-firebase/app` module is already set up.

```bash
yarn add @react-native-firebase/firestore

# If you're developing your app using iOS, run this command
cd ios/ && pod install
```

--------------------------------

### Create a Reference to a Specific Database Instance

Source: https://rnfirebase.io/database/usage

To reference a database other than the default, provide its full URL when creating the reference. This is useful for multi-database setups.

```javascript
import { firebase } from '@react-native-firebase/database';

const reference = firebase
  .app()
  .database('https://<databaseName>.<region>.firebasedatabase.app/')
  .ref('/users/123');
```

--------------------------------

### Setup Component State for FlatList

Source: https://rnfirebase.io/firestore/usage-with-flatlists

Initialize component state to manage loading status and the array of data for the FlatList. This setup is required before subscribing to Firestore data.

```javascript
import React, { useState } from 'react';
import { ActivityIndicator } from 'react-native';

function Users() {
  const [loading, setLoading] = useState(true); // Set loading to true on component mount
  const [users, setUsers] = useState([]); // Initial empty array of users

  if (loading) {
    return <ActivityIndicator />;
  }

  // ...
```

--------------------------------

### Install Firebase AI Logic

Source: https://rnfirebase.io/ai/usage

Install the Firebase AI module and its prerequisite `@react-native-firebase/app` module using Yarn.

```bash
yarn add @react-native-firebase/app
yarn add @react-native-firebase/ai
```

--------------------------------

### Install React Native Firebase App and Messaging Modules

Source: https://rnfirebase.io/messaging/usage

Install the core app module and the messaging module using Yarn. For iOS, ensure you run `pod install` afterwards.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the messaging module
yarn add @react-native-firebase/messaging

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Install React Native Firebase Analytics

Source: https://rnfirebase.io/analytics/usage

Installs the core app module and the analytics module for React Native Firebase. Includes a command for iOS pod installation.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the analytics module
yarn add @react-native-firebase/analytics

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Example HTTPS Callable Function Deployment

Source: https://rnfirebase.io/functions/usage

An example of how to define an HTTPS callable function named 'listProducts' that returns an array of data. This code would typically be deployed to Firebase.

```javascript
// Deployed HTTPS callable
exports.listProducts = functions.https.onCall(() => {
  return [
    /* ... */
    // Return some data
  ];
});

```

--------------------------------

### Install Firebase Modules

Source: https://rnfirebase.io/migrating-to-v6

Install the NPM packages for all Firebase services your application utilizes. This ensures all necessary modules are present for v6.

```bash
yarn add @react-native-firebase/admob

```

```bash
yarn add @react-native-firebase/analytics

```

```bash
yarn add @react-native-firebase/app

```

```bash
yarn add @react-native-firebase/invites

```

```bash
yarn add @react-native-firebase/auth

```

```bash
yarn add @react-native-firebase/firestore

```

```bash
yarn add @react-native-firebase/functions

```

```bash
yarn add @react-native-firebase/messaging

```

```bash
yarn add @react-native-firebase/storage

```

```bash
yarn add @react-native-firebase/crashlytics

```

```bash
yarn add @react-native-firebase/in-app-messaging

```

```bash
yarn add @react-native-firebase/iid

```

```bash
yarn add @react-native-firebase/ml

```

```bash
yarn add @react-native-firebase/perf

```

```bash
yarn add @react-native-firebase/database

```

```bash
yarn add @react-native-firebase/remote-config

```

--------------------------------

### Add RNFBAuth Pod to Podfile

Source: https://rnfirebase.io/auth/usage/installation/ios

Add the `RNFBAuth` Pod to your project's `/ios/Podfile` to integrate the authentication module. This step is necessary for manual installations.

```ruby
target 'app' do
  #  ...
  pod 'RNFBAuth', :path => '../node_modules/@react-native-firebase/auth'
end

```

--------------------------------

### Install Base App Module with Expo

Source: https://rnfirebase.io/

Use this command to install the base '@react-native-firebase/app' module for Expo projects. Ensure you are using a development build.

```bash
npx expo install @react-native-firebase/app
```

--------------------------------

### Install React Native Firebase App Module (NPM)

Source: https://rnfirebase.io/

Install the core `@react-native-firebase/app` module using NPM. This is a prerequisite for using any other React Native Firebase services.

```bash
# Using npm
npm install --save @react-native-firebase/app

```

--------------------------------

### Update Pods and Rebuild iOS Project

Source: https://rnfirebase.io/install-ios

After adding the RNFBApp Pod, navigate to the 'ios/' directory and run 'pod install --repo-update' to install the Pods. Then, rebuild your iOS project using 'npx react-native run-ios'.

```bash
cd ios/
pod install --repo-update
```

```bash
npx react-native run-ios
```

--------------------------------

### Initialize Twitter SDK

Source: https://rnfirebase.io/auth/social-auth

Initialize the Twitter SDK with your consumer key and secret before initiating a sign-in request. This setup is crucial for authenticating users via Twitter.

```javascript
import { NativeModules } from 'react-native';
const { RNTwitterSignIn } = NativeModules;

RNTwitterSignIn.init('TWITTER_CONSUMER_KEY', 'TWITTER_CONSUMER_SECRET').then(() =>
  console.log('Twitter SDK initialized'),
);
```

--------------------------------

### Get All Remote Config Values

Source: https://rnfirebase.io/remote-config/usage

Fetch all Remote Config parameters at once using the `getAll` method. This is useful for iterating through all available configurations and logging their details.

```javascript
const parameters = remoteConfig().getAll();

Object.entries(parameters).forEach($ => {
  const [key, entry] = $;
  console.log('Key: ', key);
  console.log('Source: ', entry.getSource());
  console.log('Value: ', entry.asString());
});
```

--------------------------------

### Query Firestore Documents Starting After a Specific Document

Source: https://rnfirebase.io/firestore/usage

Use `orderBy` with `startAt` and a `DocumentSnapshot` to begin a query after a specific document. This example orders users by age descending and starts after the document with ID 'DEF'.

```javascript
const userDocumentSnapshot = await firestore().collection('Users').doc('DEF').get();

firestore()
  .collection('Users')
  .orderBy('age', 'desc')
  .startAt(userDocumentSnapshot)
  .get()
  .then(querySnapshot => {
    /* ... */
  });

```

--------------------------------

### Initialize Google Sign-In SDK

Source: https://rnfirebase.io/auth/social-auth

Configure the Google Sign-In SDK with your web client ID before initiating sign-in. Ensure the `webClientId` is correctly set from your `google-services.json` file.

```javascript
import { GoogleSignin } from '@react-native-google-signin/google-signin';

GoogleSignin.configure({
  webClientId: '',
});
```

--------------------------------

### Install Crashlytics Module

Source: https://rnfirebase.io/crashlytics/usage

Install the Crashlytics module using Yarn. Ensure the `@react-native-firebase/app` module is already set up. For iOS, run `pod install` after installation.

```bash
# Install & setup the app module
yarn add @react-native-firebase/app

# Install the Crashlytics module
yarn add @react-native-firebase/crashlytics

# If you're developing your app using iOS, run this command
cd ios/ && pod install

```

--------------------------------

### Initializing Secondary Apps

Source: https://rnfirebase.io/app/usage

Demonstrates how to initialize a secondary Firebase app instance with provided credentials and configuration.

```APIDOC
## Initializing secondary apps

The module exposes an `initializeApp` method which accepts arguments containing the credentials and options for your secondary apps:

```javascript
import firebase from '@react-native-firebase/app';

// Your secondary Firebase project credentials...
const credentials = {
  clientId: '',
  appId: '',
  apiKey: '',
  databaseURL: '',
  storageBucket: '',
  messagingSenderId: '',
  projectId: '',
};

const config = {
  name: 'SECONDARY_APP',
};

await firebase.initializeApp(credentials, config);
```

Note that if you use multiple platforms, you will need to use the credentials relevant to that platform:

```javascript
import firebase from '@react-native-firebase/app';
import { Platform } from 'react-native';

// Your secondary Firebase project credentials for Android...
const androidCredentials = {
  clientId: '',
  appId: '',
  apiKey: '',
  databaseURL: '',
  storageBucket: '',
  messagingSenderId: '',
  projectId: '',
};

// Your secondary Firebase project credentials for iOS...
const iosCredentials = {
  clientId: '',
  appId: '',
  apiKey: '',
  databaseURL: '',
  storageBucket: '',
  messagingSenderId: '',
  projectId: '',
};

// Select the relevant credentials
const credentials = Platform.select({
  android: androidCredentials,
  ios: iosCredentials,
});

const config = {
  name: 'SECONDARY_APP',
};

await firebase.initializeApp(credentials, config);
```

Once created, you can confirm the app instance has been created by accessing the `apps` property on the module:

```javascript
const apps = firebase.apps;

apps.forEach(app => {
  console.log('App name: ', app.name);
});
```
```

--------------------------------

### Initiate Sign-in with Email/Password

Source: https://rnfirebase.io/auth/multi-factor-auth

Begin the sign-in process with primary credentials. If MFA is required, an 'auth/multi-factor-auth-required' error will be thrown.

```javascript
import {
  PhoneAuthProvider,
  PhoneMultiFactorGenerator,
  getAuth,
  signInWithEmailAndPassword,
  getMultiFactorResolver,
} from '@react-native-firebase/auth';

signInWithEmailAndPassword(getAuth(), email, password)
  .then(() => {
    // User has not enrolled a second factor
  })
  .catch(error => {
    const { code } = error;
    // Make sure to check if multi factor authentication is required
    if (code === 'auth/multi-factor-auth-required') {
      return;
    }

    // Other error
  });

```

--------------------------------

### Switching App Instance

Source: https://rnfirebase.io/app/usage

Explains how to switch between different initialized Firebase app instances.

```APIDOC
## Switching app instance

You can switch app instances at any time whilst developing by calling the `app` method with the name of the secondary app:

```javascript
import firebase from '@react-native-firebase/app';
import '@react-native-firebase/auth';

// Example using auth
firebase.app('SECONDARY_APP').auth().currentUser;
```

Or pass the secondary app instance you created above directly to the desired module, for example:

```javascript
import firebase from '@react-native-firebase/app';
import auth from '@react-native-firebase/auth';

// create secondary app as described above
const secondaryApp = await firebase.initializeApp(credentials, config);

// Example using auth with passing the secondary app instance
auth(secondaryApp).currentUser;
```
```

--------------------------------

### Querying with Start/End Points

Source: https://rnfirebase.io/firestore/usage

Use `startAt`, `endAt`, `startAfter`, and `endBefore` methods to query documents within a specific range. These methods require an `orderBy` clause and can accept either a value or a `DocumentSnapshot`.

```APIDOC
## Querying with Start/End Points

### Description
Query documents within a specific range using `startAt`, `endAt`, `startAfter`, or `endBefore`. These methods require an `orderBy` clause and can accept a specific value or a `DocumentSnapshot` to define the query boundaries.

### Method
`collection().orderBy(...).startAt(value | DocumentSnapshot)`
`collection().orderBy(...).endAt(value | DocumentSnapshot)`
`collection().orderBy(...).startAfter(value | DocumentSnapshot)`
`collection().orderBy(...).endBefore(value | DocumentSnapshot)`

### Example (Value Range)
```javascript
firestore()
  .collection('Users')
  .orderBy('age', 'desc')
  .startAt(18)
  .endAt(30)
  .get()
  .then(querySnapshot => {
    // Handle query results between age 18 and 30
  });
```

### Example (Document Snapshot Range)
```javascript
const userDocumentSnapshot = await firestore().collection('Users').doc('DEF').get();

firestore()
  .collection('Users')
  .orderBy('age', 'desc')
  .startAt(userDocumentSnapshot)
  .get()
  .then(querySnapshot => {
    // Handle query results starting from the DEF document
  });
```
```

--------------------------------

### App Check: Inline Provider Configuration

Source: https://rnfirebase.io/migrating-to-v25

Demonstrates initializing App Check with native provider configuration passed inline, useful when a provider instance is not needed for reuse.

```typescript
import { getApp } from '@react-native-firebase/app';
import { initializeAppCheck } from '@react-native-firebase/app-check';

await initializeAppCheck(getApp(), {
  provider: {
    providerOptions: {
      android: {
        provider: __DEV__ ? 'debug' : 'playIntegrity',
      },
      apple: {
        provider: __DEV__ ? 'debug' : 'appAttestWithDeviceCheckFallback',
      },
      web: {
        provider: 'reCaptchaV3',
        siteKey: 'your-recaptcha-site-key',
      },
    },
  },
  isTokenAutoRefreshEnabled: true,
});

```

--------------------------------

### Access Multiple Storage Buckets

Source: https://rnfirebase.io/storage/usage

Instantiate storage with the default bucket or specify a different bucket using its `gs://` URL.

```javascript
import storage, { firebase } from '@react-native-firebase/storage';

const defaultStorageBucket = storage();
const secondaryStorageBucket = firebase.app().storage('gs://my-secondary-bucket.appspot.com');

```

--------------------------------

### DocumentSnapshot - Get Nested Data

Source: https://rnfirebase.io/firestore/usage

Access deeply nested data within a document using the `get` method with a dot-notated path.

```APIDOC
## DocumentSnapshot - Get Nested Data

### Description
Access deeply nested data within a document using the `get` method with a dot-notated path.

### Method
`get(path)`

### Endpoint
`documentSnapshot.get('info.address.zipcode')`

### Parameters
#### Path Parameters
- **path** (string) - Required - A dot-notated path to the desired field.

### Request Example
```javascript
function getUserZipCode(documentSnapshot) {
  return documentSnapshot.get('info.address.zipcode');
}

firestore()
  .collection('Users')
  .doc('ABC')
  .get()
  .then(documentSnapshot => getUserZipCode(documentSnapshot))
  .then(zipCode => {
    console.log('Users zip code is: ', zipCode);
  });
```
```

--------------------------------

### Rebuild Android Project

Source: https://rnfirebase.io/analytics/usage/installation/android

Run this command after completing the manual integration steps to rebuild your Android project.

```bash
npx react-native run-android
```

--------------------------------

### App Check: Updated Import and Initialization

Source: https://rnfirebase.io/migrating-to-v25

Shows the new way to import App Check helpers and types and initialize the module with native provider configuration.

```typescript
// Now
import { getApp } from '@react-native-firebase/app';
import {
  AppCheckTokenResult,
  ReactNativeFirebaseAppCheckProvider,
  initializeAppCheck,
  getToken,
} from '@react-native-firebase/app-check';

const provider = new ReactNativeFirebaseAppCheckProvider();

provider.configure({
  android: {
    provider: __DEV__ ? 'debug' : 'playIntegrity',
  },
  apple: {
    provider: __DEV__ ? 'debug' : 'appAttestWithDeviceCheckFallback',
  },
  web: {
    provider: 'reCaptchaV3',
    siteKey: 'your-recaptcha-site-key',
  },
});

const appCheck = await initializeAppCheck(getApp(), {
  provider,
  isTokenAutoRefreshEnabled: true,
});

const result: AppCheckTokenResult = await getToken(appCheck);
console.log(result.token);

```

--------------------------------

### Serve Cloud Functions Locally

Source: https://rnfirebase.io/functions/writing-deploying-functions

Run the local development server for your Cloud Functions. This command allows you to test your functions before deploying them.

```bash
cd functions/
npm run serve

```

--------------------------------

### QuerySnapshot - Get Documents

Source: https://rnfirebase.io/firestore/usage

Retrieve all documents within a collection using the `get` method, which returns a `QuerySnapshot`. You can then iterate over the documents using `forEach`.

```APIDOC
## QuerySnapshot - Get Documents

### Description
Retrieve all documents within a collection using the `get` method, which returns a `QuerySnapshot`. You can then iterate over the documents using `forEach`.

### Method
`get()`

### Endpoint
`firestore().collection('Users').get()`

### Response
#### Success Response (QuerySnapshot)
- **size** (number) - The number of documents in the collection.
- **forEach** (function) - A method to iterate over each `DocumentSnapshot` in the `QuerySnapshot`.

### Request Example
```javascript
import firestore from '@react-native-firebase/firestore';

firestore()
  .collection('Users')
  .get()
  .then(querySnapshot => {
    console.log('Total users: ', querySnapshot.size);

    querySnapshot.forEach(documentSnapshot => {
      console.log('User ID: ', documentSnapshot.id, documentSnapshot.data());
    });
  });
```
```

--------------------------------

### List Files and Directories Recursively

Source: https://rnfirebase.io/storage/usage

Recursively list all files and directories within a storage reference, handling pagination with `pageToken`.

```javascript
import storage from '@react-native-firebase/storage';

function listFilesAndDirectories(reference, pageToken) {
  return reference.list({ pageToken }).then(result => {
    // Loop over each item
    result.items.forEach(ref => {
      console.log(ref.fullPath);
    });

    if (result.nextPageToken) {
      return listFilesAndDirectories(reference, result.nextPageToken);
    }

    return Promise.resolve();
  });
}

const reference = storage().ref('images');

listFilesAndDirectories(reference).then(() => {
  console.log('Finished listing');
});

```

--------------------------------

### Enable Multidex and Add Dependency in build.gradle

Source: https://rnfirebase.io/enabling-multidex

Configure your `android/app/build.gradle` file to enable multidex and include the multidex dependency. This is necessary when your project exceeds the 64k method limit.

```gradle
android {
    defaultConfig {
        // ...
        multiDexEnabled true // <-- ADD THIS in the defaultConfig section
    }
    // ...
}

dependencies {
  implementation 'androidx.multidex:multidex:2.0.1'  // <-- ADD THIS DEPENDENCY
}
```

--------------------------------

### DocumentSnapshot - Get Data

Source: https://rnfirebase.io/firestore/usage

Retrieve a specific document using its ID. The `get` method returns a `DocumentSnapshot` which contains the document's data and metadata.

```APIDOC
## DocumentSnapshot - Get Data

### Description
Retrieve a specific document using its ID. The `get` method returns a `DocumentSnapshot` which contains the document's data and metadata.

### Method
`get()`

### Endpoint
`firestore().collection('Users').doc('ABC').get()`

### Response
#### Success Response (DocumentSnapshot)
- **exists** (boolean) - Whether the document exists.
- **data** (function) - Returns the document's data as an object, or `undefined` if the document does not exist.

### Request Example
```javascript
import firestore from '@react-native-firebase/firestore';

firestore()
  .collection('Users')
  .doc('ABC')
  .get()
  .then(documentSnapshot => {
    console.log('User exists: ', documentSnapshot.exists);

    if (documentSnapshot.exists) {
      console.log('User data: ', documentSnapshot.data());
    }
  });
```
```

--------------------------------

### XMPP Server Setup with node-xcs

Source: https://rnfirebase.io/messaging/usage/messaging-with-xmpp

Configure a custom XMPP server using `node-xcs` to listen for incoming messages and receipts. Ensure your Firebase credentials (SenderID, ServerKey) are correctly entered.

```javascript
const Sender = require('node-xcs').Sender;

async function operation() {
  return () => {
    console.log('Listening >>>');

    // Enter firebase credentials here. {SenderID, ServerKey}
    var xcs = new Sender('XXXXXXXX', 'XXXXXXXX');

    xcs.start();

    xcs.on('message', function (messageId, from, data, category) {
      console.log('received message', messageId, from, data, category);
    });

    xcs.on('receipt', function (messageId, from, data, category) {
      console.log('received receipt', arguments);
    });

    xcs.on('error', e => console.warn('XMPP error.', e));
  };
}

async function app() {
  await operation();
}

app();

```

--------------------------------

### Listen for Remote Config Updates

Source: https://rnfirebase.io/remote-config/usage

Set up a listener to receive real-time updates for Remote Config. Ensure you activate the new configuration after it's fetched. Unsubscribe the listener when it's no longer needed to conserve resources.

```javascript
// Add a config update listener where appropriate, perhaps in app startup, or a specific app area.
// Multiple listeners are supported, so listeners may be screen-specific and only handle certain keys
// depending on application requirements
let remoteConfigListenerUnsubscriber = onConfigUpdate(getRemoteConfig(), {
  next: (update) => {
    console.log('remote-config keys updated: ' + Array.from(update.getUpdatedKeys()));

    // If you use realtime updates, the SDK fetches the new config for you.
    // However, you must activate the new config so it is in effect
    activate(getRemoteConfig());
  },
  error: (error) => {
    console.log('remote-config listener subscription error: ' + error);
  }
});

// unsubscribe the listener when no longer needed - remote config will close the network socket if there
// are no active listeners, potentially minimizing application user data and battery usage.
remoteConfigListenerUnsubscriber();

```

--------------------------------

### Get All Documents in a Collection

Source: https://rnfirebase.io/firestore/usage

Retrieve all documents within a collection using the `get` method. The `querySnapshot.size` property indicates the total number of documents, and `forEach` can iterate over them.

```javascript
import firestore from '@react-native-firebase/firestore';

firestore()
  .collection('Users')
  .get()
  .then(querySnapshot => {
    console.log('Total users: ', querySnapshot.size);

    querySnapshot.forEach(documentSnapshot => {
      console.log('User ID: ', documentSnapshot.id, documentSnapshot.data());
    });
  });

```

--------------------------------

### Install React Native Firebase App Module (Yarn)

Source: https://rnfirebase.io/

Install the core `@react-native-firebase/app` module using Yarn. This is a prerequisite for using any other React Native Firebase services.

```bash
# Using Yarn
yarn add @react-native-firebase/app

```

--------------------------------

### Configure iOS Podfile for App Check

Source: https://rnfirebase.io/app-check/usage/index

Add this `post_install` hook to your `ios/Podfile` to exclude the `i386` architecture, which can resolve Xcode compiler errors and linker problems when using the App Check module.

```ruby
installer.aggregate_targets.each do |aggregate_target|
      aggregate_target.user_project.native_targets.each do |target|
        target.build_configurations.each do |config|
          config.build_settings['ONLY_ACTIVE_ARCH'] = 'NO'
          config.build_settings['EXCLUDED_ARCHS'] = 'i386'
        end
      end
      aggregate_target.user_project.save
    end

```

--------------------------------

### Install Multiple Firebase Modules with Expo

Source: https://rnfirebase.io/

Install multiple React Native Firebase modules, such as authentication and crashlytics, simultaneously for Expo projects. This requires a development build.

```bash
npx expo install @react-native-firebase/auth @react-native-firebase/crashlytics
```

--------------------------------

### Check Available MFA Hints

Source: https://rnfirebase.io/auth/multi-factor-auth

Inspect the `resolver.hints` array to determine the available second factors for the user to choose from.

```javascript
if (resolver.hints.length > 1) {
  // Use resolver.hints to display a list of second factors to the user
}

if (resolver.hints[0].factorId === PhoneMultiFactorGenerator.FACTOR_ID) {
  // Continue with the sign-in flow
}

```

--------------------------------

### Query Data Starting from a Specific Value

Source: https://rnfirebase.io/database/usage

Retrieve data that starts from a specific reference node value based on a child's property. This is useful for pagination or filtering.

```javascript
await database().ref('users').orderByChild('age').startAt(21).once('value');

```

--------------------------------

### Add Firebase/Messaging Pod to Notification Service Extension

Source: https://rnfirebase.io/messaging/ios-notification-images

Ensure your notification service extension can access Firebase/Messaging by adding this to your Podfile. Install pods using `pod install` from the `ios` folder.

```ruby
target 'ImageNotification' do
  use_frameworks! :linkage => :static
  pod 'Firebase/Messaging'
end
```

--------------------------------

### Get download URL from StorageReference

Source: https://rnfirebase.io/migrating-to-v6

The deprecated UploadTaskSnapshot.downloadUrl property has been removed. Use StorageReference.getDownloadURL() instead.

```javascript
const downloadUrl = await storageRef.getDownloadURL();
```

--------------------------------

### Get metric returns 0 if not found

Source: https://rnfirebase.io/migrating-to-v6

The getMetric method will now return 0 if a metric cannot be found on the trace.

```javascript
const metricValue = trace.getMetric('nonExistentMetric'); // returns 0
```

--------------------------------

### List Files and Directories

Source: https://rnfirebase.io/storage/usage

Retrieves a paginated list of files and directories within a specified bucket reference. Supports fetching subsequent pages using a page token.

```APIDOC
## Listing files & directories
If you wish to view a full list of the current files & directories within a particular bucket reference, you can use the `list` method. The results are however paginated, and if more results are available you can pass a page token into the request:
```javascript
import storage from '@react-native-firebase/storage';

function listFilesAndDirectories(reference, pageToken) {
  return reference.list({ pageToken }).then(result => {
    // Loop over each item
    result.items.forEach(ref => {
      console.log(ref.fullPath);
    });

    if (result.nextPageToken) {
      return listFilesAndDirectories(reference, result.nextPageToken);
    }

    return Promise.resolve();
  });
}

const reference = storage().ref('images');

listFilesAndDirectories(reference).then(() => {
  console.log('Finished listing');
});
```
```

--------------------------------

### Get MultiFactorUser Instance

Source: https://rnfirebase.io/auth/multi-factor-auth

Obtain a `MultiFactorUser` instance for the current user. This is required before performing most multi-factor operations.

```javascript
import {
  PhoneAuthProvider,
  PhoneMultiFactorGenerator,
  getAuth,
  multiFactor,
} from '@react-native-firebase/auth';

const multiFactorUser = await multiFactor(getAuth().currentUser);
```

--------------------------------

### Initialize Firebase for Web Platform

Source: https://rnfirebase.io/

Dynamically initialize Firebase for web platforms using `initializeApp` with your Firebase configuration. This is necessary for web builds as the native configuration files are not available. Ensure this runs during your application's bootstrap process.

```javascript
import { getApp, initializeApp } from '@react-native-firebase/app';

// web requires dynamic initialization on web prior to using firebase
if (Platform.OS === 'web') {
  const firebaseConfig = {
    // ... config items pasted from firebase console for your web app here
  };

  initializeApp(firebaseConfig);
}

// ...now throughout your app, use firebase APIs normally, for example:
const firebaseApp = getApp();

```

--------------------------------

### Clean Gradle dependencies

Source: https://rnfirebase.io/migrating-to-v6

Execute the Gradle clean command in the android directory to ensure a fresh installation of dependencies.

```bash
$ cd android/
$ ./gradlew clean

```

--------------------------------

### Get Download URL

Source: https://rnfirebase.io/storage/usage

Generates a downloadable HTTP URL for a file stored in the bucket, enabling it to be served as a CDN.

```APIDOC
## Download URLs
A common use-case for Cloud Storage is to use it as a global Content Delivery Network (CDN) for your images. When uploading files to a bucket, they are not automatically available for consumption via a HTTP URL. To generate a new Download URL, you need to call the `getDownloadURL` method on a reference:
```javascript
import storage from '@react-native-firebase/storage';

const url = await storage().ref('images/profile-1.png').getDownloadURL();
```

> Images uploaded manually via the Firebase Console automatically generate a download URL.
```

--------------------------------

### Implement Microsoft Sign-In Logic

Source: https://rnfirebase.io/auth/social-auth

Handles the Microsoft sign-in flow using `signInWithRedirect`. Allows configuration of scopes and custom parameters like tenant ID for Azure AD integration.

```javascript
import { OAuthProvider, getAuth, signInWithRedirect } from '@react-native-firebase/auth';

const onMicrosoftButtonPress = async () => {
  // Generate the provider object
  const provider = new OAuthProvider('microsoft.com');
  // Optionally add scopes
  provider.addScope('offline_access');
  // Optionally add custom parameters
  provider.setCustomParameters({
    prompt: 'consent',
    // Optional "tenant" parameter for optional use of Azure AD tenant.
    // e.g., specific ID - 9aaa9999-9999-999a-a9aa-9999aa9aa99a or domain - example.com
    // defaults to "common" for tenant-independent tokens.
    tenant: 'tenant_name_or_id',
  });

  // Sign-in the user with the provider
  return signInWithRedirect(getAuth(), provider);
};
```

--------------------------------

### One-time Read of Document Data

Source: https://rnfirebase.io/firestore/usage

Perform a one-time read of a specific document using the `get` method on a `DocumentReference`.

```javascript
import firestore from '@react-native-firebase/firestore';

const user = await firestore().collection('Users').doc('ABC').get();
```

--------------------------------

### Complete Multi-Factor Sign-in

Source: https://rnfirebase.io/auth/multi-factor-auth

Create a phone credential using the verification code and then resolve the sign-in flow with a multi-factor assertion.

```javascript
const credential = PhoneAuthProvider.credential(verificationId, verificationCode);

const multiFactorAssertion = PhoneMultiFactorGenerator.assertion(credential);

resolver.resolveSignIn(multiFactorAssertion).then(userCredential => {
  // additionally onAuthStateChanged will be triggered as well
});

```

--------------------------------

### Get Multi-Factor Resolver

Source: https://rnfirebase.io/auth/multi-factor-auth

Obtain a `MultiFactorResolver` instance from the error object when MFA is required to continue the sign-in flow.

```javascript
const resolver = getMultiFactorResolver(getAuth(), error);

```

--------------------------------

### Phone Sign-In Flow - React Native

Source: https://rnfirebase.io/auth/phone-auth

This example demonstrates the complete phone sign-in flow, including handling authentication state changes, initiating the SMS code sending, and confirming the received code. Ensure you have the necessary Firebase auth listeners set up.

```javascript
import { useState, useEffect } from 'react';
import { Button, TextInput } from 'react-native';
import { getAuth, onAuthStateChanged, signInWithPhoneNumber } from '@react-native-firebase/auth';

function PhoneSignIn() {
  // If null, no SMS has been sent
  const [confirm, setConfirm] = useState(null);

  // verification code (OTP - One-Time-Passcode)
  const [code, setCode] = useState('');

  // Handle login
  function handleAuthStateChanged(user) {
    if (user) {
      // Some Android devices can automatically process the verification code (OTP) message, and the user would NOT need to enter the code.
      // Actually, if he/she tries to enter it, he/she will get an error message because the code was already used in the background.
      // In this function, make sure you hide the component(s) for entering the code and/or navigate away from this screen.
      // It is also recommended to display a message to the user informing him/her that he/she has successfully logged in.
    }
  }

  useEffect(() => {
    const subscriber = onAuthStateChanged(getAuth(), handleAuthStateChanged);
    return subscriber; // unsubscribe on unmount
  }, []);

  // Handle the button press
  async function handleSignInWithPhoneNumber(phoneNumber) {
    const confirmation = await signInWithPhoneNumber(getAuth(), phoneNumber);
    setConfirm(confirmation);
  }

  async function confirmCode() {
    try {
      await confirm.confirm(code);
    } catch (error) {
      console.log('Invalid code.');
    }
  }

  if (!confirm) {
    return (
      <Button
        title="Phone Number Sign In"
        onPress={() => handleSignInWithPhoneNumber('+1 650-555-3434')}
      />
    );
  }

  return (
    <>
      <TextInput value={code} onChangeText={text => setCode(text)} />
      <Button title="Confirm Code" onPress={() => confirmCode()} />
    </>
  );
}

```