Custom error parsing

[kevinrenskers]

My API behaves so that when the user tries to login and it fails, the error is given as a JSON body in the response like this:

{"non_field_errors":["Unable to log in with provided credentials."]}

Sadly all that I get back from CodyFire is "Something went wrong..." from here, since the error response doesn't contain a message property and it's not an array.

Would it be possible to simply give the entire JSON response back to the error? Or that I can override the error handling logic on a per-request basis?

[kevinrenskers]

Ah never mind, I see that I do have access to error.raw. Still, it would be very nice if CodyFire wouldn't make assumptions about error responses like it does now :)

[kevinrenskers]

Hm sadly the Data extension parseJSON is not public but internal, so it's not very easy to parse the raw error without duplicating this logic.

Even better of course would be to have Codable errors, strongly typed. I am now doing something like this, but would hate to do that for every request:

}.onError { error in
  if let rawErrorData = error.raw {
    let decoder = JSONDecoder()
    decoder.keyDecodingStrategy = .convertFromSnakeCase

    do {
      let decodedError = try decoder.decode(LoginError.self, from: rawErrorData)
      print("decodedError: \(decodedError.nonFieldErrors[0])")
    } catch {
      print("Well, it's not a `nonFieldErrors` type of error :p")
    }
  }
}

-----

struct LoginError: Decodable {
  let nonFieldErrors: [String]
}

[kevinrenskers]

Another good example of an error I get is from the register endpoint:

{
  "username":["A user with that username already exists."],
  "email":["Enter a valid email address."]
}

And just in case anyone has the same problem, I am currently doing something like this:

func showNetworkError(title: String, error: NetworkError) {
    if let rawErrorData = error.raw, let errorJSON = rawErrorData.parseJSON() as? [String: [String]] {
      let values = errorJSON.map { $0.value }.flatMap { $0 }
      let nicerValues = values.map { "- \($0)" }
      let string = nicerValues.joined(separator: "\n")

      let banner = GrowingNotificationBanner(title: title, subtitle: string, style: .danger)
      banner.duration = 3
      banner.show()
    }
  }

Which is used like this:

}.onError { error in
  showNetworkError(title: "Register error", error: error)
}

But yea my point still is that it would be nice if CodyFire wouldn't have hardcoded error handling strategies that don't work for everybody and else just return "Something went wrong..." :)