A NSAttributedString extension that adds a convenient method for composing a NSAttributedString with links and images.

NSAttributedString+compose.swift

import UIKit

// How to use:
/*
let label = UILabel()
let textView = UITextView()

label.attributedText = .compose(
    "Please go to ",
    .link(label: "Google",
          url: URL(string: "https://google.com")!),
    " ", .systemImage("globe")
)
let style = NSAttributedStringStyle(font: .preferredFont(forTextStyle: .body), lineSpacing: 16)
textView.attributedText = .compose(style: style,
    "Please go to ", .linkLiteral("https://google.com"), " for more details.", .systemImage("globe"),
    .lineBreak,
    "Also you can go to our ", .link(label: "Website", url: URL(string: "http://google.com")!), ".",
    .lineBreak,
    "This is another line.", .systemImage("arrow.up.bin")
)
*/

extension NSAttributedString {
    static func compose(style: NSAttributedStringStyle = .default, _ components: NSAttributedStringComponent...) -> NSAttributedString {
        let mutableAttributedString = NSMutableAttributedString()
        for c in components {
            mutableAttributedString.append(c.attributedString())
        }
        let range = NSRange(location: 0, length: mutableAttributedString.length)
        mutableAttributedString.addAttributes(style.attributes(), range: range)
        return mutableAttributedString
    }
}

struct NSAttributedStringStyle {
    static let `default` = NSAttributedStringStyle()
    let font: UIFont?
    let foregroundColor: UIColor?
    let alignment: NSTextAlignment?
    let lineSpacing: CGFloat?
    let paragraphSpacing: CGFloat?

    init(font: UIFont? = nil, foregroundColor: UIColor? = nil, alignment: NSTextAlignment? = nil, lineSpacing: CGFloat? = nil, paragraphSpacing: CGFloat? = nil) {
        self.font = font
        self.foregroundColor = foregroundColor
        self.alignment = alignment
        self.lineSpacing = lineSpacing
        self.paragraphSpacing = paragraphSpacing
    }

    func attributes() -> [NSAttributedString.Key: Any] {
        var attributes: [NSAttributedString.Key: Any] = [:]
        attributes[.font] = font
        attributes[.foregroundColor] = foregroundColor
        let paragraphStyle = NSMutableParagraphStyle()
        if let alignment = alignment {
            paragraphStyle.alignment = alignment
        }
        if let lineSpacing = lineSpacing {
            paragraphStyle.lineSpacing = lineSpacing
        }
        if let paragraphSpacing = paragraphSpacing {
            paragraphStyle.paragraphSpacing = paragraphSpacing
        }
        attributes[.paragraphStyle] = paragraphStyle
        return attributes
    }
}

enum NSAttributedStringComponent {
    case text(String)

    case link(label: String, url: URL)
    case linkLiteral(String)

    case image(UIImage?, CGSize? = nil)
    @available(iOS 13.0, *)
    case systemImage(String, tintColor: UIColor? = nil)

    case lineBreak
    case space

    func attributedString() -> NSAttributedString {
        switch self {
        case .text(let string):
            return NSAttributedString(string: string)
        case .link(let label, let url):
            return NSAttributedString(string: label, attributes: [.link: url])
        case .linkLiteral(let string):
            assert(URL(string: string) != nil)
            return Self.link(label: string, url: URL(string: string)!).attributedString()
        case .image(let image, let size):
            let attachment = NSTextAttachment()
            attachment.image = image
            if let size = size {
                attachment.bounds.size = size
            }
            return NSAttributedString(attachment: attachment)
        case .systemImage(let name, let tintColor):
            if #available(iOS 13.0, *) {
                var image = UIImage(systemName: name)
                if let tintColor = tintColor {
                    image = image?.withTintColor(tintColor)
                }
                return Self.image(image).attributedString()
            } else {
                let image = UIImage(named: name)
                return Self.image(image).attributedString()
            }
        case .lineBreak:
            return NSAttributedString(string: "\n")
        case .space:
            return Self.text(" ").attributedString()
        }
    }
}

extension NSAttributedStringComponent: ExpressibleByStringLiteral {
    init(stringLiteral value: String) {
        self = .text(value)
    }
}