This is a sample code to read barcodes with Swift.

Reference: Swift 4でQRコードを読み取る
AVFoundation(AVCaptureMetadataOutput)でバーコードリーダーを作ってみた

First of all, the info.plist contains the Add a key of Privacy - Camera Usage Description to describe the reason for using the camera. “Barcode reader reads” and so on. This phrase appears when you ask for permission to use it.