Adding a Date property to the model

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1

What encoding and decoding special code needs to be added to the server app when a model includes a Swift Date property? Eg, say you add a Date property to Acronym to track the first time this acronym came into popular use. When I send a request to create an acronym the Vapor app reports
[ ERROR ] DecodingError.typeMismatch: POST /api/acronyms Value of type ‘String’ required for key ‘dateOfFirstReportedUse’. (ErrorMiddleware.swift:26)

Thanks!

2

What does your Acronym model look like and are you expecting it to be sent in the create request or added after?

3

The Date property will be set at the time of creation of the object. I simply added the (contrived) property to the model as such.

final class Acronym: Codable {
  var id: Int?
  var short: String
  var long: String
  var dateOfFirstReportedUse: Date
  var userID: UUID

  init(short: String, long: String, dateOfFirstReportedUse: Date, userID: UUID) {
    self.short = short
    self.long = long
    self.dateOfFirstReportedUse = dateOfFirstReportedUse
    self.userID = userID
  }
}
4

So if you want to create it outside of the POST request, you can just do:

let user = try req.requireAuthenticated(User.self)
let acronym = try Acronym(short: createData.short, long: createData.long, dateOfFirstReportedUse: Date(), userID = user.requireID())

Or if you wanted to send it in the POST request it would look like:

{
    ...
    "dateOfFirstReportedUse": "2020-04-02T13:00:00Z"
}
2 Likes
5

What I needed to do is customize the content encoding/decoding for Date objects like this;

  1. Create a content.swift file in the cloud app project with this function:
public func content(config: inout ContentConfig) throws {
	let encoder = JSONEncoder()
	let decoder = JSONDecoder()

	encoder.dateEncodingStrategy = .secondsSince1970
	decoder.dateDecodingStrategy = .secondsSince1970

	config.use(encoder: encoder, for: .json)
	config.use(decoder: decoder, for: .json)
}
  1. Add this to configure.swift:
/// Register Content Config
var contentConfig = ContentConfig.default()
try content(config: &contentConfig)
services.register(contentConfig)
  1. In the iOS app set the dateEncodingStrategy property of the JSONEncoder. For example,
    in ResourceRequest.swift’s save function:
let encoder = JSONEncoder()
encoder.dateEncodingStrategy = .secondsSince1970
6

@gonzalo Do you still have issues with this?

7

No longer an issue. I solved it as described above.