Swift Editing MSMessage URL Data

Question

Main Question - How do I check if an MSMessage has already been opened by the recipient?

I have an iMessage extension in which a user can send a MSMessage to their recipient. Upon receiving the message, the recipient should be able to open it and read what the sender sent (extracting the message from the URL).

However, after reading it once (meaning upon close of extension), the message from then on when opened will tell them that they have already read the message.

How do I save information (most likely in the URL) so that the application can see if it has been opened once already by the recipient?

Something to consider: I saw something about being able to make the message expire and overall disappear, but it sounds like the user could choose to save instead. If there is a way of just deleting the message automatically, that would work too

Here is the information I encoded into the message's URL:

    var queryItems: [URLQueryItem] = []
    let plain: URLQueryItem = URLQueryItem(name: "plainText", value: msgData.plainText)
    let msg: URLQueryItem = URLQueryItem(name: "message", value: msgData.message)
    let read: URLQueryItem = URLQueryItem(name: "read", value: "false")
    queryItems.append(read)
    queryItems.append(plain)
    queryItems.append(msg)
    var components = URLComponents()
    components.queryItems = queryItems
    message.url = components.url!

Answer 1

The only reliable way I've worked out to deal with these kind of things is saved state in a local database (Realm) where the message provides a persistent key.

I am fairly certain you cannot push data back into the url field when you receive a message. It's only writable when creating new ones.