Random Swift image placeholder URL.

gistfile1.txt

extension URL {
    /// Use `let url = URL.placeholderImageUrl`
    static var placeholderImageUrl: URL? {
        let size = Int.random(in: 150..<800)
        return placeholderImageUrl(with: CGSize(width: size, height: size))
    }

    /// Use `let url = URL.placeholderImageUrl(with: CGSize(width: 200, height: 200))`
    static func placeholderImageUrl(with size: CGSize) -> URL? {
        let services = [
            "www.fillmurray.com",
            "www.placecage.com",
            "www.stevensegallery.com",
            "placekitten.com",
            "placebear.com",
        ]
        return URL(string: "https://\(services[Int.random(in: 0..<services.count)])/\(Int(size.width))/\(Int(size.height))")
    }
}