KingFisher+LinkPresentationIconProvider.swift

import KingFisher

struct KFLinkPresentationIconProvider: ImageDataProvider {
    
    let url: URL
    let cacheKey: String
    
    init(url: URL, cacheKey: String? = nil) {
        self.url = url
        self.cacheKey = cacheKey ?? url.absoluteString
    }

    func data(handler: @escaping (Result<Data, Error>) -> Void) {
        
        LPMetadataProvider().startFetchingMetadata(for: url) { (metadata, metadataError) in
            if let metadataError = metadataError {
                return handler(.failure(metadataError))
            }
            
            metadata?.iconProvider?.loadObject(of: UIImage.self) { result in
                switch result {
                case .success(let icon):
                    handler(.success(icon.pngData()!))
                case .failure(let error):
                    handler(.failure(error))
                }
            }
        }
    }
}

NSItemProvider+Combine.swift

import Foundation
import Combine

extension NSItemProvider {
    
    func loadObject<Object: NSItemProviderReading>(of type: Object.Type, completionHandler: @escaping (Result<Object, Error>) -> Void) {
        self.loadObject(ofClass: type) { (object, error) in
            if let error = error {
                completionHandler(.failure(error))
            } else if let object = object as? Object {
                completionHandler(.success(object))
            } else {
                let error = NSError(domain: NSItemProvider.errorDomain, code: NSItemProvider.ErrorCode.unknownError.rawValue)
                completionHandler(.failure(error))
            }
        }
    }
    
    func loadObjectPublisher<Object: NSItemProviderReading>(of type: Object.Type) -> AnyPublisher<Object, Error> {
        let subject = PassthroughSubject<Object, Error>()
        
        self.loadObject(of: type) { result in
            switch result {
            case .success(let object):
                subject.send(object)
            case .failure(let error):
                subject.send(completion: .failure(error))
            }
        }
        
        return subject.eraseToAnyPublisher()
    }
}