We're close to shipping our first React Native app. Once the app is out, we would want to send updates over the air to bypass the sluggish AppStore review process, and speed up release cycles. We've built react-native-auto-updater to do just that.
Does Apple permit this?
Yes! Section 3.3.2 of the iOS Developer Program allows it "provided that such scripts and code do not change the primary purpose of the Application by providing features or functionality that are inconsistent with the intended and advertised purpose of the Application."
Does Google permit this?
Of course!
React Native jsbundle can be easily over a couple of megabytes. On cellular connections, downloading them more often than what is needed is not a good idea. To tackle that problem, we need to decide if the bundle needs to be downloaded at all.
We solve this by shipping the app with an initial version of the jsbundle, this reduces the latency during the initial startup. Then we start querying for available update, and download the updated jsbundle. All subsequent runs of the app uses this updated bundle.
In order to decide whether to download the jsbundle or not, we need to know some meta-information about the bundle. For react-native-auto-updater, we store this meta-information as a form of a JSON file somewhere on the internet. The format of the JSON is as follows
{
"version": "1.1.0",
"minContainerVersion": "1.0",
"url": {
"url": "/s/3klfuwm74sfnj0w/main.jsbundle?raw=1",
"isRelative": true
}
}Here's what the fields in the JSON mean:
version— this is the version of the bundle file (in major.minor.patch format)minContainerVersion— this is the minimum version of the container (native) app that is allowed to download this bundle (this is needed because adding a new React Native component to your app might result into changed native app, hence, going through the AppStore review process)url.url— this is whereReactNativeAutoUpdaterwill download the JS bundle fromurl.isRelative— this tells if the provided URL is a relative URL (when set totrue, you need to set the hostname by using the method(void)setHostnameForRelativeDownloadURLs:(NSString*)hostname;)
react-native-auto-updater needs know the location of this JSON file upon initialization.
Here's a GIF'ed screencast of react-native-auto-updater in action.
Don't forget to provide react-native-auto-updater with the metadata file for the JS code that is shipped with the app. Metadata in this file is used to compare the shipped JS code with updates. Thanks to @arbesfeld for pointing out this bug.
react-native-auto-updater is available under the MIT license. See the LICENSE file for more info.