Getting "Swift runtime failure: Unexpectedly found nil while implicitly unwrapping an Optional value" error

[jaysonng]

New Issue Checklist

• [x] I am not disclosing a vulnerability.
• [x] I have searched through existing issues.
• [x] I can reproduce the issue with the latest versions of Parse Server and the Parse Swift SDK.

Issue Description

"Thread 4: Swift runtime failure: Unexpectedly found nil while implicitly unwrapping an Optional value"

when running query with .includeAll() on my @main app file.

The error specifically comes from the firstCommand() function in Query.swift

Steps to reproduce

Call some query on the same view where you run ParseSwift.initialize()

In my case, ParseSwift.initilize is called within init() in a Task { }

I receive this warning in the console for the few times that it does not crash

nw_resolver_start_query_timer_block_invoke [C1.1.1] Query fired: did not receive all answers in time for xxxxxxxxx:443

Actual Outcome

A lot of the times it crashes with the said error. only some of the time does it work as expected.

Expected Outcome

There should be no crash and the query should be called after initialization of Parse.

Environment

Client

• Parse Swift SDK version: 5.4.1
• Xcode version: 14.3
• Operating system (iOS, macOS, watchOS, etc.): iPad OS, iOS, MacOS simulator
• Operating system version: 16.4.1

Server

• Parse Server version: 5.2.4
• Operating system: ``
• Local or remote host (AWS, Azure, Google Cloud, Heroku, Digital Ocean, etc): Heroku

Database

• System (MongoDB or Postgres): MongoDB
• Database version: ``
• Local or remote host (MongoDB Atlas, mLab, AWS, Azure, Google Cloud, etc): Local Heroku

Logs

[cbaker6]

Call some query on the same view where you run ParseSwift.initialize()

You are calling your initializer way too late if you are calling it in a view. In addition, placing the Swift SDK init in a view may cause it to be called multiple times, which can lead to a ton of other issues.

The Swift SDK should be called once, and it should be called early when the app opens, which is why it has historically been in the AppDelegate.

I can try to submit a partial fix, but your current design will continue to lead to issues as views can be regenerated, causing the SDK to be reinitialized.

[jaysonng]

I see. I just moved it to the @main view.

I guess ill copy how you have it setup on carekit with the appdelegate. :) thanks again

[cbaker6]

The linked PR and version should fix the direct issue you are facing.

I guess ill copy how you have it setup on carekit with the appdelegate.

If you are looking through the CareKit example, this branch is cleaner and will be merged in the near future: https://github.com/netreconlab/CareKitSample-ParseCareKit/tree/newCareKit

You will want to setup your AppDelegate in a similar way:

• Make sure AppDelegate is wrapped with @UIApplicationDelegateAdaptor(AppDelegate.self). You can pass it through the environment if you intend to use AppDelegate in other places of your app: https://github.com/netreconlab/CareKitSample-ParseCareKit/blob/f5965788f28eee84a4eab382ab785e3badd6a1c6/OCKSample/OCKSampleApp.swift#L15-L22
• Make your AppDelegate class conform to ObservableObject and use @Published for any properties you want to update your views https://github.com/netreconlab/CareKitSample-ParseCareKit/blob/f5965788f28eee84a4eab382ab785e3badd6a1c6/OCKSample/AppDelegate.swift#L39-L42
• Then you can place the ParseSwift init in didFinishLaunching like you use to do in UIKit lifecycle apps: https://github.com/netreconlab/CareKitSample-ParseCareKit/blob/b362e420952d2c50038dd7871711b532b18e83ac/OCKSample/Extensions/AppDelegate%2BUIApplicationDelegate.swift#L13-L27
  • Note that PCKUtility.configureParse() calls ParseSwift init, so if you are interested in using a .plist file to configure ParseSwift, see: https://github.com/netreconlab/ParseCareKit/blob/566f68ef230e4285eb9e19a3d1045947d5a74eef/Sources/ParseCareKit/PCKUtility.swift#L18-L94