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API Reference

Updates

The Updates API from expo allows you to programatically control and respond to over-the-air updates to your app.

Platform Compatibility

Android DeviceAndroid EmulatoriOS DeviceiOS SimulatorWeb

Installation

expo install expo-updates

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

Since extra setup is required to use this module in bare React Native apps, for easiest use we recommend using a template project with expo-updates already installed. You can use expo init --template=expo-template-bare-minimum to initialize a new project from such a template.
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 JS from your computer while developing. To test manual updates in the Expo client, run expo publish and then open the published version of your app with the Expo client. To test manual updates in Bare workflow apps, make a release build with npm run ios --configuration Release or npm run android --variant Release (you don't need to submit this build to the App/Play Store to test).

Legacy API

In previous Expo SDK versions, the Updates module was imported from the expo package. It has now moved to its own separate package, expo-updates. The new module has a similar but slightly different JS API from the Updates module included with the expo package. The Updates module export was removed from the expo package in SDK 39, so you need to switch to the new module and API.
The changes in the new API are as follows:
  • Updates.fetchUpdateAsync no longer accepts any arguments. (It still resolves when an update is finished downloading.)
  • The listener in Updates.addListener will only receive events about automatically downloaded updates, not downloads triggered manually by Updates.fetchUpdateAsync.
  • Event names have changed: DOWNLOAD_FINISHED has become UPDATE_AVAILABLE, and DOWNLOAD_START events are no longer emitted.
  • Updates.reloadFromCache has been renamed to Updates.reloadAsync, and Updates.reload has been removed.

API

import * as Updates from 'expo-updates';

Constants

Constants

Updates.isEmergencyLaunch

(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

(object) 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

(string) The name of the release channel currently configured in this standalone or bare app.

Updates.updateId

(string | null) If expo-updates is enabled, the UUID that uniquely identifies the currently running update. 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.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 resolves 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 instructions above. 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.

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.

Returns

A Promise that resolves to an object with the following keys:
  • isAvailable (boolean) -- true if an update is available, false if you're already running the most up-to-date JS bundle.
  • manifest (object) -- If isAvailable is true, the manifest of the available update. Undefined otherwise.
The Promise rejects if the app is in development mode, or if there is an unexpected error 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 resolves to an object with the following keys:
  • isNew (boolean) -- true if the fetched bundle is new (i.e. a different version than what's currently running), false otherwise.
  • manifest (object) -- If isNew is true, the manifest of the newly downloaded update. Undefined otherwise.
The Promise rejects if the app is in development mode, or if there is an unexpected error communicating with the server.

Updates.addListener(eventListener)

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.

Arguments

  • eventListener ((event: UpdateEvent) => void) -- A function that will be invoked with an instance of UpdateEvent and should not return any value.

Returns

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

Related Types

EventSubscription

An object returned from addListener.
  • remove() (function) -- Unsubscribe the listener from future updates.

UpdateEvent

An object that is passed into each event listener when an auto-update check has occurred.
  • type (string) -- Type of the event (see UpdateEventType).
  • manifest (object) -- If type === Updates.UpdateEventType.UPDATE_AVAILABLE, the manifest of the newly downloaded update. Undefined otherwise.
  • message (string) -- If type === Updates.UpdateEventType.ERROR, the error message. Undefined otherwise.

UpdateEventType

  • Updates.UpdateEventType.UPDATE_AVAILABLE -- 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.
  • Updates.UpdateEventType.NO_UPDATE_AVAILABLE -- No updates are available, and the most up-to-date bundle of this experience is already running.
  • Updates.UpdateEventType.ERROR -- An error occurred trying to fetch the latest 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.