out-of-band invatation with request~attach embedding json can't be decoded

[kukgini]

I made out-of-band invitation with credential-offer from AcaPy. but AF.Swift produce error when decode it.

Error occured here: OutOfBandInvitation.swift:(31~45)

 public required init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        label = try values.decode(String.self, forKey: .label)
        goalCode = try values.decodeIfPresent(String.self, forKey: .goalCode)
        goal = try values.decodeIfPresent(String.self, forKey: .goal)
        accept = try values.decodeIfPresent([String].self, forKey: .accept)
        handshakeProtocols = try values.decodeIfPresent([HandshakeProtocol].self, forKey: .handshakeProtocols)
        requests = try values.decodeIfPresent([Attachment].self, forKey: .requests) <--- error occured here
        services = try values.decode([OutOfBandDidCommService].self, forKey: .services)
        if services.count == 0 {
            throw AriesFrameworkError.frameworkError("Decoding out-of-band invitation failed: no services found")
        }
        imageUrl = try values.decodeIfPresent(String.self, forKey: .imageUrl)
        try super.init(from: decoder)
}

Error message here:

typeMismatch(Swift.String, Swift.DecodingError.Context(codingPath: [CodingKeys(stringValue: "requests~attach", intValue: nil), _JSONKey(stringValue: "Index 0", intValue: 0), CodingKeys(stringValue: "data", intValue: nil), CodingKeys(stringValue: "json", intValue: nil)], debugDescription: "Expected to decode String but found a dictionary instead.", underlyingError: nil))

see the Invitation code in attachments.
out-of-band-invitation.txt

[conanoc]

It's a bug that Attachment decoding fails when the attachment data contains json field instead of base64 field.

[conanoc]

This is a known issue and I don't know how to handle general json data in an attachment.