Cordova Permit iOS getUserMedia Plugin

A Cordova plugin allowing the embedded web app (loaded from a file inside the app bundle) to call navigator.mediaDevices.getUserMedia (part of browser WebRTC support) and show a camera view without triggering a new iOS permission dialog every time.

The plugin does nothing on Android, has no JavaScript interface, and no configuration options.

Requirements

• iOS 15.0 or later is required
• Tested with cordova-ios v6.2.0

How it works

During application load, the plugin creates and installs a custom WKUIDelegate on the WKWebView. Whenever the JS code in the web view calls navigator.mediaDevices.getUserMedia, the web view asks the delegate for a “permission decision” by sending it a webView:requestMediaCapturePermissionForOrigin:initiatedByFrame:type:decisionHandler: message. The plugin checks the protocol of the origin, and if it’s file then it makes an “allow” decision, which suppresses the permission dialog. For all other origins it makes the default “prompt” decision, so if you’re running getUserMedia from web pages loaded from outside the app, they will continue to prompt for permission. If you need to allow that, feel free to fork this plugin.

Note that all other WKUIDelegate messages are forwarded to the original delegate that was in place when this plugin is loaded, so the other functions of CDVWebViewUIDelegate should continue to work. Be aware this might not work properly if you’re using another plugin that tries to do something similar.

Note that the app itself needs permission to access the camera through the normal iOS mechanism. That permission dialog will be triggered by the first call you make to getUserMedia. You can (and should, because it’s an App Store review failure if you don’t) customize the text of that popup to explain exactly what your app needs the camera for. Do that in your Cordova config.xml something like this:

<config-file overwrite="true" parent="NSCameraUsageDescription" platform="ios" target="*-Info.plist">
    <string>The app uses the camera to scan QR codes</string>
</config-file>

License

The project is MIT licensed: MIT.