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Expo Updates

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The expo-updates library allows you to programmatically control and respond to new updates made available to your app.

Platform Compatibility

Android DeviceAndroid EmulatoriOS DeviceiOS SimulatorWeb

Installation

Terminal
npx expo install expo-updates

If you're installing this in a bare React Native app, you should also follow these additional installation instructions.

Usage

Most of the methods and constants in this module can only be used or tested in release mode; they do not make sense in debug builds where you always load the latest JavaScript from your computer while in development.

To test manual updates in the Expo Go app, run eas update and then open the published version of your app with Expo Go.

To test manual updates with managed workflow standalone apps, you can create a .apk or a simulator build or , or make a release build locally with expo run:android --variant release and expo run:ios --configuration Release.

To test manual updates in bare workflow apps, make a release build with expo run:android --variant release or expo run:ios --configuration Release (you don't need to submit this build to the store to test).

Check for updates manually

The expo-updates library exports a variety of functions to interact with updates once the app is already running. In some scenarios, you may want to check if updates are available or not. This can be done manually by using checkForUpdateAsync() as shown in the example below:

App.js
import { View, Button } from 'react-native';
import * as Updates from 'expo-updates';

function App() {
  async function onFetchUpdateAsync() {
    try {
      const update = await Updates.checkForUpdateAsync();

      if (update.isAvailable) {
        await Updates.fetchUpdateAsync();
        await Updates.reloadAsync();
      }
    } catch (error) {
      // You can also add an alert() to see the error message in case of an error when fetching updates.
      alert(`Error fetching latest Expo update: ${error}`);
    }
  }

  return (
    <View>
      <Button title="Fetch update" onPress={onFetchUpdateAsync} />
    </View>
  );
}

API

import * as Updates from 'expo-updates';

Constants

Updates.channel

Type: string | null


The channel name of the current build, if configured for use with EAS Update. Null otherwise.

Updates.createdAt

Type: Date | null


If expo-updates is enabled, this is a Date object representing the creation time of the update that's currently running (whether it was embedded or downloaded at runtime).

In development mode, or any other environment in which expo-updates is disabled, this value is null.

Updates.isEmergencyLaunch

Type: boolean


expo-updates does its very best to always launch monotonically newer versions of your app so you don't need to worry about backwards compatibility when you put out an update. In very rare cases, it's possible that expo-updates may need to fall back to the update that's embedded in the app binary, even after newer updates have been downloaded and run (an "emergency launch"). This boolean will be true if the app is launching under this fallback mechanism and false otherwise. If you are concerned about backwards compatibility of future updates to your app, you can use this constant to provide special behavior for this rare case.

Updates.manifest

Type: Partial<Manifest>


If expo-updates is enabled, this is the manifest object for the update that's currently running.

In development mode, or any other environment in which expo-updates is disabled, this object is empty.

Updates.releaseChannel

Type: string


The name of the release channel currently configured in this standalone or bare app when using classic updates. When using Expo Updates, the value of this field is always "default".

Updates.runtimeVersion

Type: string | null


The runtime version of the current build.

Updates.updateId

Type: string | null


The UUID that uniquely identifies the currently running update if expo-updates is enabled. The UUID is represented in its canonical string form (xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx) and will always use lowercase letters. In development mode, or any other environment in which expo-updates is disabled, this value is null.

Methods

Updates.checkForUpdateAsync()

Checks the server to see if a newly deployed update to your project is available. Does not actually download the update. This method cannot be used in development mode, and the returned promise will be rejected if you try to do so.

Checking for an update uses a device's bandwidth and battery life like any network call. Additionally, updates served by Expo may be rate limited. A good rule of thumb to check for updates judiciously is to check when the user launches or foregrounds the app. Avoid polling for updates in a frequent loop.

Returns

  • Promise<UpdateCheckResult>

A promise that fulfills with an UpdateCheckResult object.

The promise rejects if the app is in development mode, or if there is an unexpected error or timeout communicating with the server.

Updates.fetchUpdateAsync()

Downloads the most recently deployed update to your project from server to the device's local storage. This method cannot be used in development mode, and the returned promise will be rejected if you try to do so.

Returns


A promise that fulfills with an UpdateFetchResult object.

The promise rejects if the app is in development mode, or if there is an unexpected error or timeout communicating with the server.

Updates.reloadAsync()

Instructs the app to reload using the most recently downloaded version. This is useful for triggering a newly downloaded update to launch without the user needing to manually restart the app.

It is not recommended to place any meaningful logic after a call to await Updates.reloadAsync(). This is because the promise is resolved after verifying that the app can be reloaded, and immediately before posting an asynchronous task to the main thread to actually reload the app. It is unsafe to make any assumptions about whether any more JS code will be executed after the Updates.reloadAsync method call resolves, since that depends on the OS and the state of the native module and main threads.

This method cannot be used in development mode, and the returned promise will be rejected if you try to do so.

Returns


A promise that fulfills right before the reload instruction is sent to the JS runtime, or rejects if it cannot find a reference to the JS runtime. If the promise is rejected in production mode, it most likely means you have installed the module incorrectly. Double check you've followed the installation instructions. In particular, on iOS ensure that you set the bridge property on EXUpdatesAppController with a pointer to the RCTBridge you want to reload, and on Android ensure you either call UpdatesController.initialize with the instance of ReactApplication you want to reload, or call UpdatesController.setReactNativeHost with the proper instance of ReactNativeHost.

Event Subscriptions

Updates.addListener(listener)

NameTypeDescription
listener(event: UpdateEvent) => void

A function that will be invoked with an UpdateEvent instance and should not return any value.


Adds a callback to be invoked when updates-related events occur (such as upon the initial app load) due to auto-update settings chosen at build-time.

Returns

  • EventSubscription

An EventSubscription object on which you can call remove() to unsubscribe the listener.

Types

UpdateCheckResult

The result of checking for a new update.

NameTypeDescription
isAvailableboolean

true if an update is available, false if the app is already running the latest available update.

manifest
(optional)
Manifest

If isAvailable is true, the manifest of the available update, and undefined otherwise.

UpdateEvent

An object that is passed into each event listener when an auto-update check occurs.

NameTypeDescription
manifest
(optional)
Manifest

If type is Updates.UpdateEventType.UPDATE_AVAILABLE, the manifest of the newly downloaded update, and undefined otherwise.

message
(optional)
string

If type is Updates.UpdateEventType.ERROR, the error message, and undefined otherwise.

typeUpdateEventType

Type of the event.

UpdateFetchResult

The result of fetching a new update.

NameTypeDescription
isNewboolean

true if the fetched bundle is new (that is, a different version than what's currently running), false otherwise.

manifest
(optional)
Manifest

If isNew is true, the manifest of the newly downloaded update, and undefined otherwise.

Enums

UpdateEventType

The types of update-related events.

ERROR

UpdateEventType.ERROR = "error"

An error occurred trying to fetch the latest update.

NO_UPDATE_AVAILABLE

UpdateEventType.NO_UPDATE_AVAILABLE = "noUpdateAvailable"

No updates are available, and the most up-to-date update is already running.

UPDATE_AVAILABLE

UpdateEventType.UPDATE_AVAILABLE = "updateAvailable"

A new update has finished downloading to local storage. If you would like to start using this update at any point before the user closes and restarts the app on their own, you can call Updates.reloadAsync() to launch this new update.

Error Codes

CodeDescription
ERR_UPDATES_DISABLEDA method call was attempted when the Updates module was disabled, or the application was running in development mode
ERR_UPDATES_RELOADAn error occurred when trying to reload the application and it could not be reloaded. For bare workflow apps, double check the setup steps for this module to ensure it has been installed correctly and the proper native initialization methods are called.
ERR_UPDATES_CHECKAn unexpected error occurred when trying to check for new updates. Check the error message for more information.
ERR_UPDATES_FETCHAn unexpected error occurred when trying to fetch a new update. Check the error message for more information.