Hot Updater - Self-hosted OTA updates for React Native

The `checkForUpdate` function checks if there is an available update for the app by comparing the current app version and platform with the update server's bundle information.

Usage

Use checkForUpdate to verify if an update bundle is available. The function reuses the update source configured in HotUpdater.wrap() or HotUpdater.init().

import { HotUpdater } from "@hot-updater/react-native";

// First, configure baseURL with init
HotUpdater.init({
  baseURL: "<your-update-server-url>",
});

// Use checkForUpdate - it reuses the configured baseURL
async function checkForAppUpdate() {
  try {
    const updateInfo = await HotUpdater.checkForUpdate({
      updateStrategy: "appVersion",
      requestHeaders: {
        Authorization: "Bearer <your-access-token>",
      },
    });

    if (!updateInfo) {
      return {
        status: "UP_TO_DATE",
      };
    }

    /**
     * You can apply updates using one of two methods:
     *
     * Method 1: Use the updateBundle() method from the updateInfo object
     * - A convenience method built into the return value from checkForUpdate
     * - Performs the same function as HotUpdater.updateBundle with all required arguments pre-filled
     */
    await updateInfo.updateBundle();

    /**
     * Method 2: Call HotUpdater.updateBundle() directly
     * - Explicitly pass the necessary values extracted from updateInfo
     */
    // await HotUpdater.updateBundle({
    //   bundleId: updateInfo.id,
    //   fileUrl: updateInfo.fileUrl,
    //   fileHash: updateInfo.fileHash,
    //   status: updateInfo.status,
    // });

    if (updateInfo.shouldForceUpdate) {
      await HotUpdater.reload();
    }
    return updateInfo;
  } catch (error) {
    console.error("Failed to check for update:", error);
    return null;
  }
}

Important: HotUpdater.wrap or HotUpdater.init Required

When using checkForUpdate, configure Hot Updater first with HotUpdater.wrap() or HotUpdater.init(). This is required for proper crash detection and rollback functionality.

import { HotUpdater } from "@hot-updater/react-native";
import { useEffect } from "react";
import YourApp from "./YourApp";

function App() {
  useEffect(() => {
    HotUpdater.checkForUpdate({
      updateStrategy: "appVersion",
      requestHeaders: {
        Authorization: "Bearer <your-access-token>",
      },
    }).then(async (updateInfo) => {
      if (updateInfo) {
        await updateInfo.updateBundle();
        if (updateInfo.shouldForceUpdate) {
          await HotUpdater.reload();
        }
      }
    }).catch((error) => {
      console.error("Failed to check for update:", error);
    });
  }, []);

  return <YourApp />;
}

HotUpdater.init({
  baseURL: "<your-update-server-url>",
});

export default App;

HotUpdater.init() configures Hot Updater without the unnecessary HOC that manual wrap would create:

HotUpdater.init({
  baseURL: "<your-update-server-url>",
});

Without wrap or init, calling checkForUpdate will throw an error with instructions on how to fix it.

Parameters

The checkForUpdate function accepts the following parameters:

Parameter	Type	Required	Description
`updateStrategy`	`"appVersion"` \| `"fingerprint"`	✅	Update detection strategy for this check.
`channel`	`string`	❌	Channel to check. The switch is persisted only after the returned update is applied.
`requestHeaders`	`Record<string, string>`	❌	Optional headers to include in the update request.
`requestTimeout`	`number`	❌	Request timeout in milliseconds (default: 5000).
`onError`	`(error: Error) => void`	❌	Error callback.

The update source is always the baseURL or resolver configured by HotUpdater.wrap() or HotUpdater.init(); it cannot be overridden in checkForUpdate.

How It Works

When you call checkForUpdate, the function uses the configured baseURL and the provided updateStrategy to construct the appropriate endpoint URL:

For updateStrategy: "appVersion": GET {baseURL}/app-version/:platform/:appVersion/:channel/:minBundleId/:bundleId/:cohort
For updateStrategy: "fingerprint": GET {baseURL}/fingerprint/:platform/:fingerprintHash/:channel/:minBundleId/:bundleId/:cohort

For example, if you configured baseURL: "https://your-update-server.com/api/update-check" in wrap, the function automatically appends the correct path and parameters.

Return Value

The function returns an update object or null if the app is up to date.

Property	Type	Description
`id`	`string`	Bundle identifier.
`shouldForceUpdate`	`boolean`	Whether the app should reload immediately after download.
`fileUrl`	`string \| null`	Bundle archive URL, or `null` for a rollback without an archive.
`fileHash`	`string \| null`	Bundle hash or signature used by native verification.
`message`	`string \| null`	Optional update message.
`status`	`"ROLLBACK" \| "UPDATE"`	Update operation.
`updateBundle`	`() => Promise<boolean>`	Applies this result with the required values pre-filled.

Prefer the returned updateBundle() helper so the values from that update check are applied together.

Example Return Value

The JSON response provides the data fields; the client adds the callable updateBundle() helper.

{
  "id": "01952bbd-e7b2-7931-aee8-2e2187caa0ce",
  "shouldForceUpdate": true,
  "status": "UPDATE",
  "fileUrl": "https://example.com/bundles/update.bundle",
  "fileHash": "0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef",
  "message": "This is a test message"
}