Deleting / setting a pointer to nil

Client SDKs ParseSwift SDK
#1

Hi, I need help trying to understand if I’m doing something wrong here. Whatever I’ve tried, I can’t seem to remove a pointer from my object and set it to nil.

  func removeProfilePhoto(for userProfile: UserProfile) async throws -> UserProfile? {
    var workingProfile = userProfile
    workingProfile.photo = nil
    let savedProfile = try await workingProfile.save()
    return savedProfile
  }

photo is a pointer to another object

Screen Shot 2021-11-06 at 1.19.33 AM

and every time I run this function, I check the dashboard but alas, the photo pointer is still there.

is there a special way to remove pointers from an object? I’ve tried googling but I nothing.

thanks in advance.

#2

The reason why setting the value to nil doesn’t work is here:

Follow the procedure here to set a property to nil. Basically, you use ParseOperation to unset the property:

func removeProfilePhoto(for userProfile: UserProfile) async throws -> UserProfile? {
    let operations = userProfile.operation
       .unset(("photo", \.photo))
    return try await operations.save()
}
1 Like
#3

ha.

The one place I forgot to check was the repo issues lol.

Thank you.

#4

It is the docs too:

JS Guide

API Documentation:

#5

This question was about the Swift SDK, the JS docs won’t help as they are for a different language.

#6

So how do you go about setting a pointer field?

#7

The playgrounds shows how to go about most of the basic functionality of the SDK:

Specifically:

#8

Sorry I should have been more specific.

I have an object that contains a bool and a ParseFile like this:

struct ProfilePicture: ParseObject, Identifiable, Decodable
{
	// Mandatory properties
	var ACL: ParseACL?
	var createdAt: Date?
	var originalData: Data?
	var objectId: String?
	var updatedAt: Date?
	
	// Custom properties
	var userProfilePicture: ParseFile?
	var verified: Bool?
}

And I have a pointer in my user object like this:

struct User: ParseUser, ParseObject
{
	// Mandatory properties
	var ACL: ParseACL?
	var authData: [String: [String: String]?]?
	var createdAt: Date?
	var email: String?
	var emailVerified: Bool?
	var originalData: Data?
	var objectId: String?
	var password: String?
	var updatedAt: Date?
	var username: String?
	
	// Custom properties
	var firstName: String?
	var lastName: String?
	var matchInfo: MatchInfo?
	var profilePicture: ProfilePicture?
}

I learned from this post how to set the userProfilePicture field to nil using unset, but how to I go about assigning a new ProfilePicture object to the user field? I tried this code:

let imageData = unwrapImage.pngData()
let parseImageFile = ParseFile(data: imageData!)
var profilePicture = ProfilePicture()
profilePicture.verified = false
profilePicture.userProfilePicture = parseImageFile
profilePicture.save { _ in
	var currentUser = User.current
	currentUser?.profilePicture = profilePicture
	currentUser?.save { _ in
		User.current?.fetch(includeKeys: ["*"]) { result in
		}
	}
}

But it does not save the ProfilePicture object.

#9

It looks like you missed saving the returned object from the Parse Server, so your code is probably saving multiple objects because you are referencing an unsaved profilePicture:

// Using completion blocks...
profilePicture.save { result in
  switch result {
  case .success(let updatedProfile):
    var currentUser = User.current
    currentUser?.profilePicture = updatedProfile
    currentUser?.save { _ in
      User.current?.fetch(includeKeys: ["*"]) { _ in }
    }
  case .failure(let error):
     // handle error
  }
}

// Using async/await may make it easier to see...

do {
  let updatedProfile = try await profilePicture.save()
  var currentUser = User.current
  currentUser?.profilePicture = updatedProfile
  let updatedUser = try await currentUser?.save()
  let fetchedUser = try await updatedUser?.fetch()
  ...
} catch {
  // handle error
}