Expo 更新

一个使你的应用能够管理应用代码远程更新的库。

Android

iOS

tvOS

Included in Expo Go

GitHub

npm

更新日志

Bundled version:

~55.0.1

expo-updates 是一个库，可让你的应用管理应用代码的远程更新。它会与已配置的远程更新服务通信，以获取可用更新的信息。

安装

expo-updates 库可以通过 EAS Update 自动配置，EAS Update 是一个托管服务，用于管理并向你的应用提供更新。要开始使用 EAS Update，请按照入门指南中的说明进行操作。

另外，在需要使用不同的远程更新服务，或者配置仅在原生文件中指定的情况下，也可以手动配置 expo-updates 库。

手动安装、配置和自定义远程更新服务

Terminal

- npx expo install expo-updates

如果你是在 bare React Native app 中安装此库，或者在一个通过手动配置原生代码的通用应用中安装，请遵循这些安装说明。

如果使用 app config 进行配置，则可以通过至少设置以下应用配置属性来配置此库：

updates.url：实现 Expo Updates protocol 的远程服务 URL
runtimeVersion：一个 runtime version

远程服务必须实现 Expo Updates protocol。EAS Update 就是这样的一个服务，但也可以将此库与自定义服务器一起使用。

自定义 Expo Updates 服务器

自定义服务器及使用该服务器的应用的示例实现

配置

有一些构建时配置选项用于控制该库的行为。对于大多数应用，这些配置值都在 app config 的 updates 属性下进行设置。

App config property	默认值	iOS plist/dictionary key	Android meta-data name	Android Map key
`updates.enabled`	`true`	`EXUpdatesEnabled`	`expo.modules.updates.ENABLED`	`enabled`
`updates.url`	(无)	`EXUpdatesURL`	`expo.modules.updates.EXPO_UPDATE_URL`	`updateUrl`
`updates.requestHeaders`	(无)	`EXUpdatesRequestHeaders`	`expo.modules.updates.UPDATES_CONFIGURATION_REQUEST_HEADERS_KEY`	`requestHeaders`
`runtimeVersion`	(无)	`EXUpdatesRuntimeVersion`	`expo.modules.updates.EXPO_RUNTIME_VERSION`	`runtimeVersion`
`updates.checkAutomatically`	`ALWAYS`	`EXUpdatesCheckOnLaunch`	`expo.modules.updates.EXPO_UPDATES_CHECK_ON_LAUNCH`	`checkOnLaunch`
`updates.fallbackToCacheTimeout`	`0`	`EXUpdatesLaunchWaitMs`	`expo.modules.updates.EXPO_UPDATES_LAUNCH_WAIT_MS`	`launchWaitMs`
`updates.useEmbeddedUpdate`	`true`	`EXUpdatesHasEmbeddedUpdate`	`expo.modules.updates.HAS_EMBEDDED_UPDATE`	`hasEmbeddedUpdate`
`updates.codeSigningCertificate`	(无)	`EXUpdatesCodeSigningCertificate`	`expo.modules.updates.CODE_SIGNING_CERTIFICATE`	`codeSigningCertificate`
`updates.codeSigningMetadata`	(无)	`EXUpdatesCodeSigningMetadata`	`expo.modules.updates.CODE_SIGNING_METADATA`	`codeSigningMetadata`
`updates.assetPatternsToBeBundled`	(无)	N/A	N/A	N/A
`updates.disableAntiBrickingMeasures`	`false`	`EXUpdatesDisableAntiBrickingMeasures`	`expo.modules.updates.DISABLE_ANTI_BRICKING_MEASURES`	`disableAntiBrickingMeasures`
`updates.enableBsdiffPatchSupport`	`false`	`EXUpdatesEnableBsdiffPatchSupport`	`expo.modules.updates.ENABLE_BSDIFF_PATCH_SUPPORT`	`enableBsdiffPatchSupport`

两个核心必需配置项是：

updates.url：该库获取远程更新的 URL
runtimeVersion：一个 runtime version

按照 EAS Update 的入门指南操作时，这些会自动配置。

运行时版本

每次为你的应用构建二进制文件时，它都会包含构建时存在的原生代码和配置，以及原生配置，而这一独特组合会由一个称为运行时版本（runtime version）的字符串表示。一个远程更新会针对某个运行时版本，这意味着只有具有匹配运行时版本的二进制文件才能加载该远程更新。

手动配置

可以通过在配置字段中设置字符串值来手动管理运行时版本。

{
  "expo": {
    "runtimeVersion": "<runtime_version_string>"
  }
}

使用运行时版本策略自动配置

运行时版本策略会从项目中已存在的另一项信息推导出运行时版本。它们可以在 runtimeVersion 配置字段中按如下方式设置：

{
  "expo": {
    "runtimeVersion": {
      "policy": "<policy_name>"
    }
  }
}

可用的策略类型：

appVersion

"appVersion" 策略适用于希望根据应用版本来定义其运行时兼容性的项目。

例如，在某个项目中，其 app config 包含如下内容：

{
  "expo": {
    "runtimeVersion": {
      "policy": "appVersion"
    },
    "version": "1.0.0",
    "ios": {
      "buildNumber": "1"
    },
    "android": {
      "versionCode": 1
    }
  }
}

"appVersion" 策略会将运行时版本设置为项目当前的 "version" 属性。在这种情况下，Android 和 iOS 构建以及任何更新的运行时版本都将是 "1.0.0"。

对于包含自定义原生代码且会在每次公开发布后更新 "version" 字段的项目来说，此策略非常适合。要提交应用，应用商店要求每个提交的构建都具有更新后的原生版本号，因此如果你希望确保安装在用户设备上的每个版本都有不同的运行时版本，那么此策略会很方便。

使用此策略时，每次有公开发布时都需要手动更新 app config 中的 "version" 字段；不过对于 Play Store 的 Internal Test Track 和 App Store 的 TestFlight 上传，你可以依赖 eas.json 中的 "autoIncrement" 选项来替你管理版本。

nativeVersion

"nativeVersion" 策略适用于希望根据项目当前的 "version" 和 "versionCode"（Android）或 "buildNumber"（iOS）属性来定义其运行时兼容性的项目。

例如，在某个项目中，其 app config 包含如下内容：

{
  "expo": {
    "runtimeVersion": {
      "policy": "nativeVersion"
    },
    "version": "1.0.0",
    "ios": {
      "buildNumber": "1"
    },
    "android": {
      "versionCode": 1
    }
  }
}

Android 和 iOS 构建以及任何更新的运行时版本都将是 "[version]([buildNumber|versionCode])" 的组合，在这种情况下将是 "1.0.0(1)"。

对于包含自定义原生代码且会为每次构建更新原生版本号（iOS 使用 "buildNumber"，Android 使用 "versionCode"）的项目来说，此策略非常适合。要提交应用，应用商店要求每个提交的构建都具有更新后的原生版本号，因此如果你想确保上传到 Play Store 的 Internal Test Track 和 App Store 的 TestFlight 分发工具的每个应用都有不同的 runtimeVersion，那么此策略会很方便。

需要注意的是，此策略要求在每次构建之间手动管理原生版本号。

另外，如果你为 Android 和 iOS 选择了不同的原生版本，最终会得到具有不同运行时版本的构建和更新。

fingerprint

"fingerprint" 运行时版本策略会自动为你计算运行时版本，包括通过 SDK 升级或添加自定义原生代码等变更。

{
  "expo": {
    "runtimeVersion": {
      "policy": "fingerprint"
    }
  }
}

此策略适用于有或没有自定义原生代码的项目。它通过在构建和更新期间使用 @expo/fingerprint 包来计算项目哈希，以确定构建-更新兼容性（也称为 runtime）。

原生配置与覆盖

如果你的项目不使用 Continuous Native Generation，这些配置值也可以在应用的原生配置文件中设置，或者在原生代码初始化期间被覆盖。

原生配置说明

在 Android 上，这些选项作为 meta-data 标签设置在 AndroidManifest.xml 文件中（如果使用自动设置，则会与安装期间添加的标签相邻）。你也可以在运行时使用 UpdatesController.overrideConfiguration() 设置或覆盖它们。

在 iOS 上，这些属性作为键设置在 Expo.plist 文件中。你也可以通过调用 AppController.overrideConfiguration 在运行时设置或覆盖它们。

导入供 Objective-C++ 使用的 Swift 生成头文件

如果你的 iOS 原生代码或 AppDelegate.mm 使用 Objective-C++ 编写，则需要添加以下导入，以引用 EXUpdatesAppController 上的方法。这仅在运行时覆盖配置时才有必要。

#import "ExpoModulesCore-Swift.h"
#import "EXUpdatesInterface-Swift.h"
#import "EXUpdates-Swift.h"

用法

默认情况下，expo-updates 会在应用启动时检查更新。如果有可用更新，它会下载更新并在应用下次重启时应用该更新。你可以使用上面的 checkAutomatically 和 fallbackToCacheTimeout 配置选项来调整这种启动行为。

该库还提供了各种常量，用于检查当前更新，以及一些函数，用于在应用代码中自定义更新行为（在启动之后）。例如，一种常见的替代使用模式是在应用启动后手动检查更新，而不是在启动时执行默认检查。

示例：手动检查更新

你可以按照以下步骤将应用配置为手动检查更新：

将 checkAutomatically 配置值设为 ON_ERROR_RECOVERY 或 NEVER，以禁用该库的默认启动行为。

添加以下代码以检查可用更新、下载它们并重新加载：

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) {
      // 你也可以添加一个 alert()，以便在获取更新时出错的情况下查看错误信息。
      alert(`Error fetching latest Expo update: ${error}`);
    }
  }

  return (
    <View>
      <Button title="获取更新" onPress={onFetchUpdateAsync} />
    </View>
  );
}

测试

该库中的大多数方法和常量只能在发布构建中使用或测试。在调试构建中，默认行为始终是从开发服务器加载最新的 JavaScript。你可以构建一个具有与发布构建相同更新行为的应用调试版本。这样的应用不会从你的开发服务器打开最新的 JavaScript — 它会像发布构建一样加载已发布的更新。这对于在应用未连接到开发服务器时调试其行为可能很有用。

要在开发构建中测试更新内容，请运行 eas update，然后在你的开发构建中浏览该更新。请注意，这只是在模拟更新在应用中的外观，并且在开发构建运行时，大部分 Updates API 都不可用。

要在发布构建中测试更新，你可以创建一个 .apk 或一个模拟器构建，或者使用 npx expo run:android --variant release 和 npx expo run:ios --configuration Release 在本地制作一个发布构建（你不需要将此构建提交到商店进行测试）。发布构建中可使用完整的 Updates API。

要在 Expo Go 中测试更新内容，请运行 eas update，然后在 Expo Go 中浏览该更新。请注意，这只是在模拟更新在应用中的外观，并且在 Expo Go 运行时，大部分 Updates API 都不可用。另请注意，仅支持使用与 Expo Go 兼容的库的更新。

API

import * as Updates from 'expo-updates';

Constants

`Updates.channel`

Android

iOS

tvOS

Type: string | null

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

Expo Go and development builds are not set to a specific channel and can run any updates compatible with their native runtime. Therefore, this value will always be null when running an update on Expo Go or a development build.

`Updates.checkAutomatically`

Android

iOS

tvOS

Type: UpdatesCheckAutomaticallyValue | null

Determines if and when expo-updates checks for and downloads updates automatically on startup.

`Updates.createdAt`

Android

iOS

tvOS

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.emergencyLaunchReason`

Android

iOS

tvOS

Type: string | null

If isEmergencyLaunch is set to true, this will contain a string error message describing what failed during initialization.

`Updates.isEmbeddedLaunch`

Android

iOS

tvOS

Type: boolean

This will be true if the currently running update is the one embedded in the build, and not one downloaded from the updates server.

`Updates.isEmergencyLaunch`

Android

iOS

tvOS

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.isEnabled`

Android

iOS

tvOS

Type: boolean

Whether expo-updates is enabled. This may be false in a variety of cases including:

enabled set to false in configuration
missing or invalid URL in configuration
missing runtime version or SDK version in configuration
error accessing storage on device during initialization

When false, the embedded update is loaded.

`Updates.latestContext`

Android

iOS

tvOS

Type: UpdatesNativeStateMachineContext

`Updates.launchDuration`

Android

iOS

tvOS

Type: number | null

Number of milliseconds it took to launch.

`Updates.manifest`

Android

iOS

tvOS

Type: Partial<Manifest>

If expo-updates is enabled, this is the manifest (or classic 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.runtimeVersion`

Android

iOS

tvOS

Type: string | null

The runtime version of the current build.

`Updates.updateId`

Android

iOS

tvOS

Type: string | null

The UUID that uniquely identifies the currently running update. The UUID is represented in its canonical string form and will always use lowercase letters. This value is null when running in a local development environment or any other environment where expo-updates is disabled.

Example

"xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"

Hooks

`useUpdates()`

Android

iOS

tvOS

Hook that obtains information on available updates and on the currently running update.

Returns:

UseUpdatesReturnType

Example

UpdatesDemo.tsx

import { StatusBar } from 'expo-status-bar';
import * as Updates from 'expo-updates';
import { useEffect } from 'react';
import { Button, Text, View } from 'react-native';

export default function UpdatesDemo() {
  const {
    currentlyRunning,
    isUpdateAvailable,
    isUpdatePending
  } = Updates.useUpdates();

  useEffect(() => {
    if (isUpdatePending) {
      // Update has successfully downloaded; apply it now
      Updates.reloadAsync();
    }
  }, [isUpdatePending]);

  // If true, we show the button to download and run the update
  const showDownloadButton = isUpdateAvailable;

  // Show whether or not we are running embedded code or an update
  const runTypeMessage = currentlyRunning.isEmbeddedLaunch
    ? 'This app is running from built-in code'
    : 'This app is running an update';

  return (
    <View style={styles.container}>
      <Text style={styles.headerText}>Updates Demo</Text>
      <Text>{runTypeMessage}</Text>
      <Button onPress={() => Updates.checkForUpdateAsync()} title="Check manually for updates" />
      {showDownloadButton ? (
        <Button onPress={() => Updates.fetchUpdateAsync()} title="Download and run update" />
      ) : null}
      <StatusBar style="auto" />
    </View>
  );
}

Classes

`ExpoUpdatesModule`

Android

iOS

tvOS

Type: Class extends NativeModule<UpdatesEvents> implements UpdatesModuleInterface

ExpoUpdatesModule Properties

`hideReloadScreen`

Android

iOS

tvOS

Type: () => Promise<void>

`setUpdateRequestHeadersOverride`

Android

iOS

tvOS

Type: (requestHeaders: Record<string, string> | null) => void

`setUpdateURLAndRequestHeadersOverride`

Android

iOS

tvOS

Type:

(configOverride: {
  requestHeaders: Record<string, string> | null, 
  updateUrl: string
} | null) => void

`showReloadScreen`

Android

iOS

tvOS

Type: (options?: ReloadScreenOptions | null) => Promise<void>

Methods

`Updates.checkForUpdateAsync()`

Android

iOS

tvOS

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 in Expo Go or if the app is in development mode, or if there is an unexpected error or timeout communicating with the server. It also rejects when expo-updates is not enabled.

`Updates.clearLogEntriesAsync()`

Android

iOS

tvOS

Clears existing expo-updates log entries.

For now, this operation does nothing on the client. Once log persistence has been implemented, this operation will actually remove existing logs.

Returns:

Promise<void>

A promise that fulfills if the clear operation was successful.

The promise rejects if there is an unexpected error in clearing the logs.

`Updates.fetchUpdateAsync()`

Android

iOS

tvOS

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.

Note: reloadAsync() can be called after promise resolution to reload the app using the most recently downloaded version. Otherwise, the update will be applied on the next app cold start.

Returns:

Promise<UpdateFetchResult>

A promise that fulfills with an UpdateFetchResult object.

The promise rejects in Expo Go or if the app is in development mode, or if there is an unexpected error or timeout communicating with the server. It also rejects when expo-updates is not enabled.

`Updates.getExtraParamsAsync()`

Android

iOS

tvOS

Retrieves the current extra params.

This method cannot be used in Expo Go or development mode. It also rejects when expo-updates is not enabled.

Returns:

Promise<Record<string, string>>

`Updates.readLogEntriesAsync(maxAge)`

Android

iOS

tvOS

Parameter	Type	Description
maxAge(optional)	`number`	Sets the max age of retrieved log entries in milliseconds. Default to `3600000` ms (1 hour). Default:`3600000`

Retrieves the most recent expo-updates log entries.

Returns:

Promise<UpdatesLogEntry[]>

A promise that fulfills with an array of UpdatesLogEntry objects;

The promise rejects if there is an unexpected error in retrieving the logs.

`Updates.reloadAsync(options)`

Android

iOS

tvOS

Parameter	Type
options(optional)	`{ reloadScreenOptions: ReloadScreenOptions }`

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. Unlike Expo.reloadAppAsync() provided by the expo package, this function not only reloads the app but also changes the loaded JavaScript bundle to that of the most recently downloaded update.

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 Expo Go or development mode, and the returned promise will be rejected if you try to do so. It also rejects when expo-updates is not enabled.

Returns:

Promise<void>

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.

`Updates.setExtraParamAsync(key, value)`

Android

iOS

tvOS

Parameter	Type
key	`string`
value	`string \| null \| undefined`

Sets an extra param if value is non-null, otherwise unsets the param. Extra params are sent as an Expo Structured Field Value Dictionary in the Expo-Extra-Params header of update requests. A compliant update server may use these params when selecting an update to serve.

This method cannot be used in Expo Go or development mode. It also rejects when expo-updates is not enabled.

Returns:

Promise<void>

`Updates.setUpdateRequestHeadersOverride(requestHeaders)`

Experimental

•

Android

iOS

tvOS

Parameter	Type
requestHeaders	`Record<string, string> \| null`

Overrides updates request headers in runtime from build time. This method allows you to load specific updates with custom request headers. Use this method at your own risk, as it may cause unexpected behavior. Learn more about use cases and limitations.

Returns:

void

`Updates.setUpdateURLAndRequestHeadersOverride(configOverride)`

Experimental

•

Android

iOS

tvOS

Parameter	Type
configOverride	`{ requestHeaders: Record<string, string>, updateUrl: string } \| null`

Overrides updates URL and reuqest headers in runtime from build time. This method allows you to load specific updates from a URL that you provide. Use this method at your own risk, as it may cause unexpected behavior. Because of the risk, this method requires disableAntiBrickingMeasures to be set to true in the app.json file. Learn more about use cases and limitations.

Returns:

void

Interfaces

`ReloadScreenImageSource`

Android

iOS

tvOS

Image source that can be used for the reload screen.

Property	Type	Description
height(optional)	`number`	Height of the image in pixels.
scale(optional)	`number`	Scale factor of the image.
url(optional)	`string`	URL to the image.
width(optional)	`number`	Width of the image in pixels.

`ReloadScreenOptions`

Android

iOS

tvOS

Configuration options for customizing the reload screen appearance.

Property	Type	Description
backgroundColor(optional)	`string`	Background color for the reload screen. Default:`'#ffffff'`
fade(optional)	`boolean`	Whether to fade out the reload screen when hiding. Default:`false`
image(optional)	`string \| number \| ReloadScreenImageSource`	Custom image to display on the reload screen.
imageFullScreen(optional)	`boolean`	Whether to display the image at the full screen size. Default:`false`
imageResizeMode(optional)	`'contain' \| 'cover' \| 'center' \| 'stretch'`	How to resize the custom image to fit the screen. Default:`'contain'`
spinner(optional)	`{ color: string, enabled: boolean, size: 'small' \| 'medium' \| 'large' }`	Configuration for the loading spinner.

`UpdatesModuleInterface`

Android

iOS

tvOS

Common interface for all native module implementations (android, ios, web).

Property	Type	Description
channel	`string`	Can be empty string
checkAutomatically	`UpdatesCheckAutomaticallyNativeValue`	-
checkForUpdateAsync	`() => Promise<UpdateCheckResultRollBack \| UpdateCheckResultNotAvailable \| Omit<UpdateCheckResultAvailable, "manifest"> & ({ manifestString: string; } \| { manifest: Manifest; })>`	-
clearLogEntriesAsync	`() => Promise<void>`	-
commitTime(optional)	`string`	-
emergencyLaunchReason	`string \| null`	-
fetchUpdateAsync	`() => Promise<UpdateFetchResultFailure \| UpdateFetchResultRollBackToEmbedded \| Omit<UpdateFetchResultSuccess, "manifest"> & ({ manifestString: string; } \| { manifest: Manifest; })>`	-
getExtraParamsAsync	`() => Promise<Record<string, string>>`	-
initialContext	`UpdatesNativeStateMachineContext & { downloadedManifestString: string, lastCheckForUpdateTimeString: string, latestManifestString: string, rollbackString: string }`	-
isEmbeddedLaunch	`boolean`	-
isEmergencyLaunch	`boolean`	-
isEnabled	`boolean`	-
isUsingEmbeddedAssets(optional)	`boolean`	-
launchDuration	`number \| null`	-
localAssets(optional)	`Record<string, string>`	-
manifest(optional)	`Manifest`	Only for: iOS -
manifestString(optional)	`string`	Only for: Android -
readLogEntriesAsync	`(maxAge: number) => Promise<UpdatesLogEntry[]>`	-
reload	`() => Promise<void>`	-
runtimeVersion	`string`	Can be empty string
setExtraParamAsync	`(key: string, value: string \| null) => Promise<void>`	-
shouldDeferToNativeForAPIMethodAvailabilityInDevelopment	`boolean`	-
updateId(optional)	`string`	-

Types

`CurrentlyRunningInfo`

Android

iOS

tvOS

Structure encapsulating information on the currently running app (either the embedded bundle or a downloaded update).

Property	Type	Description
channel(optional)	`string`	The channel name of the current build, if configured for use with EAS Update, `undefined` otherwise.
createdAt(optional)	`Date`	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 undefined.
emergencyLaunchReason	`string \| null`	If `isEmergencyLaunch` is set to true, this will contain a string error message describing what failed during initialization.
isEmbeddedLaunch	`boolean`	This will be true if the currently running update is the one embedded in the build, and not one downloaded from the updates server.
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.
launchDuration(optional)	`number`	Number of milliseconds it took to launch.
manifest(optional)	`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.
runtimeVersion(optional)	`string`	The runtime version of the current build.
updateId(optional)	`string`	The UUID that uniquely identifies the currently running update if `expo-updates` is enabled. The UUID is represented in its canonical string form and will always use lowercase letters. In development mode, or any other environment in which `expo-updates` is disabled, this value is undefined. Example `"xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"`

`Manifest`

Android

iOS

tvOS

Literal Type: union

Acceptable values are: ExpoUpdatesManifest | EmbeddedManifest

`UpdateCheckResult`

Android

iOS

tvOS

Literal Type: union

The result of checking for a new update.

Acceptable values are: UpdateCheckResultRollBack | UpdateCheckResultAvailable | UpdateCheckResultNotAvailable

`UpdateCheckResultAvailable`

Android

iOS

tvOS

The update check result when a new update is found on the server.

Property	Type	Description
isAvailable	`true`	Whether an update is available. This property is false for a roll back update.
isRollBackToEmbedded	`false`	Whether a roll back to embedded update is available.
manifest	`Manifest`	The manifest of the update when available.
reason	`undefined`	If no new update is found, this contains one of several enum values indicating the reason.

`UpdateCheckResultNotAvailable`

Android

iOS

tvOS

The update check result if no new update was found.

Property	Type	Description
isAvailable	`false`	Whether an update is available. This property is false for a roll back update.
isRollBackToEmbedded	`false`	Whether a roll back to embedded update is available.
manifest	`undefined`	The manifest of the update when available.
reason	`UpdateCheckResultNotAvailableReason`	If no new update is found, this contains one of several enum values indicating the reason.

`UpdateCheckResultRollBack`

Android

iOS

tvOS

The update check result when a rollback directive is received.

Property	Type	Description
isAvailable	`false`	Whether an update is available. This property is false for a roll back update.
isRollBackToEmbedded	`true`	Whether a roll back to embedded update is available.
manifest	`undefined`	The manifest of the update when available.
reason	`undefined`	If no new update is found, this contains one of several enum values indicating the reason.

`UpdateFetchResult`

Android

iOS

tvOS

Literal Type: union

The result of fetching a new update.

Acceptable values are: UpdateFetchResultSuccess | UpdateFetchResultFailure | UpdateFetchResultRollBackToEmbedded

`UpdateFetchResultFailure`

Android

iOS

tvOS

The failed result of fetching a new update.

Property	Type	Description
isNew	`false`	Whether the fetched update is new (that is, a different version than what's currently running). Always `false` when `isRollBackToEmbedded` is `true`.
isRollBackToEmbedded	`false`	Whether the fetched update is a roll back to the embedded update.
manifest	`undefined`	The manifest of the fetched update.

`UpdateFetchResultRollBackToEmbedded`

Android

iOS

tvOS

The roll back to embedded result of fetching a new update.

Property	Type	Description
isNew	`false`	Whether the fetched update is new (that is, a different version than what's currently running). Always `false` when `isRollBackToEmbedded` is `true`.
isRollBackToEmbedded	`true`	Whether the fetched update is a roll back to the embedded update.
manifest	`undefined`	The manifest of the fetched update.

`UpdateFetchResultSuccess`

Android

iOS

tvOS

The successful result of fetching a new update.

Property	Type	Description
isNew	`true`	Whether the fetched update is new (that is, a different version than what's currently running). Always `true` when `isRollBackToEmbedded` is `false`.
isRollBackToEmbedded	`false`	Whether the fetched update is a roll back to the embedded update.
manifest	`Manifest`	The manifest of the fetched update.

`UpdateInfo`

Android

iOS

tvOS

Literal Type: union

Combined structure representing any type of update.

Acceptable values are: UpdateInfoNew | UpdateInfoRollback

`UpdateInfoNew`

Android

iOS

tvOS

Structure representing a new update.

Property	Type	Description
createdAt	`Date`	For all types of updates, this is a `Date` object representing the creation time or commit time of the update.
manifest	`Manifest`	For updates of type `UpdateInfoType.NEW`, this is the manifest for the update.
type	`UpdateInfoType.NEW`	The type of update.
updateId	`string`	For updates of type `UpdateInfoType.NEW`, this is a string that uniquely identifies the update. For the manifests used in the current Expo Updates protocol (including EAS Update), this represents the update's UUID in its canonical string form and will always use lowercase letters. Example `"xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"`

`UpdateInfoRollback`

Android

iOS

tvOS

Structure representing a rollback directive.

Property	Type	Description
createdAt	`Date`	For all types of updates, this is a `Date` object representing the creation time or commit time of the update.
manifest	`undefined`	For updates of type `UpdateInfoType.ROLLBACK`, this is always set to `undefined`.
type	`UpdateInfoType.ROLLBACK`	The type of update.
updateId	`undefined`	For updates of type `UpdateInfoType.ROLLBACK`, this is always set to `undefined`.

`UpdatesCheckAutomaticallyNativeValue`

Android

iOS

tvOS

Literal Type: string

Acceptable values are: 'ALWAYS' | 'ERROR_RECOVERY_ONLY' | 'NEVER' | 'WIFI_ONLY'

`UpdatesEvents`

Android

iOS

tvOS

Property	Type	Description
Expo.nativeUpdatesStateChangeEvent	`(params: any) => void`	-

`UpdatesLogEntry`

Android

iOS

tvOS

An object representing a single log entry from expo-updates logging on the client.

Property	Type	Description
assetId(optional)	`string`	If present, the unique ID or hash of an asset associated with this log entry.
code	`UpdatesLogEntryCode`	One of the defined code values for `expo-updates` log entries.
level	`UpdatesLogEntryLevel`	One of the defined log level or severity values.
message	`string`	The log entry message.
stacktrace(optional)	`string[]`	If present, an Android or iOS native stack trace associated with this log entry.
timestamp	`number`	The time the log was written, in milliseconds since Jan 1 1970 UTC.
updateId(optional)	`string`	If present, the unique ID of an update associated with this log entry.

`UseUpdatesReturnType`

Android

iOS

tvOS

The type returned by useUpdates().

Property	Type	Description
availableUpdate(optional)	`UpdateInfo`	If a new available update has been found, either by using `checkForUpdateAsync()`, or by the `UpdateEvent` listener in `useUpdates()`, this will contain the information for that update.
checkError(optional)	`Error`	If an error is returned from either the startup check for updates, or a call to `checkForUpdateAsync()`, the error description will appear here.
currentlyRunning	`CurrentlyRunningInfo`	Information on the currently running app.
downloadedUpdate(optional)	`UpdateInfo`	If an available update has been downloaded, this will contain the information for that update.
downloadError(optional)	`Error`	If an error is returned from either a startup update download, or a call to `fetchUpdateAsync()`, the error description will appear here.
downloadProgress(optional)	`number`	If `isDownloading` is true, this will be a number from 0 to 1 representing the progress of the download. A value of 0 means the download has just started, and a value of 1 means it is complete. This value will update more continuously if the server provides a `Content-Length` header for the asset requests.
isChecking	`boolean`	True if the app is currently checking for a new available update from the server.
isDownloading	`boolean`	True if the app is currently downloading an update from the server.
isRestarting	`boolean`	True if the app is currently in the process of restarting.
isStartupProcedureRunning	`boolean`	Whether the startup procedure is still running. This may happen if the fallbackToCacheTimeout is shorter than the time taken to fetch a new update during app launch.
isUpdateAvailable	`boolean`	True if a new available update has been found, false otherwise.
isUpdatePending	`boolean`	True if a new available update is available and has been downloaded.
lastCheckForUpdateTimeSinceRestart(optional)	`Date`	A `Date` object representing the last time this client checked for an available update, or `undefined` if no check has yet occurred since the app started. Does not persist across app reloads or restarts.
restartCount	`number`	Number of times the JS has been restarted (for example, by calling reloadAsync) since app cold start.

Enums

`UpdateCheckResultNotAvailableReason`

Android

iOS

tvOS

`NO_UPDATE_AVAILABLE_ON_SERVER`

UpdateCheckResultNotAvailableReason.NO_UPDATE_AVAILABLE_ON_SERVER ＝ "noUpdateAvailableOnServer"

No update manifest or rollback directive received from the update server.

`ROLLBACK_NO_EMBEDDED`

UpdateCheckResultNotAvailableReason.ROLLBACK_NO_EMBEDDED ＝ "rollbackNoEmbeddedConfiguration"

A rollback directive was received from the update server, but this app has no embedded update.

`ROLLBACK_REJECTED_BY_SELECTION_POLICY`

UpdateCheckResultNotAvailableReason.ROLLBACK_REJECTED_BY_SELECTION_POLICY ＝ "rollbackRejectedBySelectionPolicy"

A rollback directive was received from the update server, but the directive does not pass the configured selection policy.

`UPDATE_PREVIOUSLY_FAILED`

UpdateCheckResultNotAvailableReason.UPDATE_PREVIOUSLY_FAILED ＝ "updatePreviouslyFailed"

An update manifest was received from the update server, but the update has been previously launched on this device and never successfully launched.

`UPDATE_REJECTED_BY_SELECTION_POLICY`

UpdateCheckResultNotAvailableReason.UPDATE_REJECTED_BY_SELECTION_POLICY ＝ "updateRejectedBySelectionPolicy"

An update manifest was received from the update server, but the update is not launchable, or does not pass the configured selection policy.

`UpdateInfoType`

Android

iOS

tvOS

The different possible types of updates. Currently, the only supported type is UpdateInfoType.NEW, indicating a new update that can be downloaded and launched on the device. In the future, other types of updates may be added to this list.

`NEW`

UpdateInfoType.NEW ＝ "new"

This is the type for new updates found on or downloaded from the update server, that are launchable on the device.

`ROLLBACK`

UpdateInfoType.ROLLBACK ＝ "rollback"

This type is used when an update is a directive to roll back to the embedded bundle.

`UpdatesCheckAutomaticallyValue`

Android

iOS

tvOS

The possible settings that determine if expo-updates will check for updates on app startup. By default, Expo will check for updates every time the app is loaded. Set this to ON_ERROR_RECOVERY to disable automatic checking unless recovering from an error. Set this to NEVER to completely disable automatic checking.

`NEVER`

UpdatesCheckAutomaticallyValue.NEVER ＝ "NEVER"

Automatic update checks are off, and update checks must be done through the JS API.

`ON_ERROR_RECOVERY`

UpdatesCheckAutomaticallyValue.ON_ERROR_RECOVERY ＝ "ON_ERROR_RECOVERY"

Only checks for updates when the app starts up after an error recovery.

`ON_LOAD`

UpdatesCheckAutomaticallyValue.ON_LOAD ＝ "ON_LOAD"

Checks for updates whenever the app is loaded. This is the default setting.

`WIFI_ONLY`

UpdatesCheckAutomaticallyValue.WIFI_ONLY ＝ "WIFI_ONLY"

Only checks for updates when the app starts and has a Wi-Fi connection.

`UpdatesLogEntryCode`

Android

iOS

tvOS

The possible code values for expo-updates log entries

`ASSETS_FAILED_TO_LOAD`

UpdatesLogEntryCode.ASSETS_FAILED_TO_LOAD ＝ "AssetsFailedToLoad"

`INITIALIZATION_ERROR`

UpdatesLogEntryCode.INITIALIZATION_ERROR ＝ "InitializationError"

`JS_RUNTIME_ERROR`

UpdatesLogEntryCode.JS_RUNTIME_ERROR ＝ "JSRuntimeError"

`NONE`

UpdatesLogEntryCode.NONE ＝ "None"

`NO_UPDATES_AVAILABLE`

UpdatesLogEntryCode.NO_UPDATES_AVAILABLE ＝ "NoUpdatesAvailable"

`UNKNOWN`

UpdatesLogEntryCode.UNKNOWN ＝ "Unknown"

`UPDATE_ASSETS_NOT_AVAILABLE`

UpdatesLogEntryCode.UPDATE_ASSETS_NOT_AVAILABLE ＝ "UpdateAssetsNotAvailable"

`UPDATE_CODE_SIGNING_ERROR`

UpdatesLogEntryCode.UPDATE_CODE_SIGNING_ERROR ＝ "UpdateCodeSigningError"

`UPDATE_FAILED_TO_LOAD`

UpdatesLogEntryCode.UPDATE_FAILED_TO_LOAD ＝ "UpdateFailedToLoad"

`UPDATE_HAS_INVALID_SIGNATURE`

UpdatesLogEntryCode.UPDATE_HAS_INVALID_SIGNATURE ＝ "UpdateHasInvalidSignature"

`UPDATE_SERVER_UNREACHABLE`

UpdatesLogEntryCode.UPDATE_SERVER_UNREACHABLE ＝ "UpdateServerUnreachable"

`UpdatesLogEntryLevel`

Android

iOS

tvOS

The possible log levels for expo-updates log entries

`DEBUG`

UpdatesLogEntryLevel.DEBUG ＝ "debug"

`ERROR`

UpdatesLogEntryLevel.ERROR ＝ "error"

`FATAL`

UpdatesLogEntryLevel.FATAL ＝ "fatal"

`INFO`

UpdatesLogEntryLevel.INFO ＝ "info"

`TRACE`

UpdatesLogEntryLevel.TRACE ＝ "trace"

`WARN`

UpdatesLogEntryLevel.WARN ＝ "warn"

错误代码

代码	描述
`ERR_UPDATES_DISABLED`	在 Updates 库被禁用时，或应用程序正在开发模式下运行时，尝试调用某个方法
`ERR_UPDATES_RELOAD`	尝试重新加载应用程序时发生错误，且无法重新加载。对于裸 React Native 应用，请再次检查该库的设置步骤，以确保已正确安装并调用了正确的原生初始化方法。
`ERR_UPDATES_CHECK`	尝试检查新更新时发生了意外错误。有关更多信息，请查看错误消息。
`ERR_UPDATES_FETCH`	尝试获取新更新时发生了意外错误。有关更多信息，请查看错误消息。
`ERR_UPDATES_READ_LOGS`	尝试读取日志条目时发生了意外错误。有关更多信息，请查看错误消息。
`ERR_NOT_AVAILABLE_IN_DEV_CLIENT`	在开发构建中运行时，该方法不可用。应使用发布构建来测试此方法。