When we try to export CapturedRoom getting cannotCreateNode(path: "/9EE71ED0F8D6415496A7B9F0C3671DB0321") in

Question

We are using the RoomPlan API to capture data, which is stored in the 'CapturedRoom' variable in our code (referred to as 'finalResult'). We then attempt to save a USDZ file in the file manager. Sometimes it works, but other times, we encounter issues like the one below

Coding Error: in _IsValidPathForCreatingPrim at line 3338 of usd/stage.cpp -- Path must be an absolute path: <>

cannotCreateNode(path: "/9EE71ED0F8D6415496A7B9F0C3671DB0321")

This is that code we are using for shaving CapturedRoom data

func saveFileLocal() {
      if let finalResult {
          let fm = FileManager.default
          let documentsURL = fm.urls(for: .documentDirectory, in: .userDomainMask).first!
          //let documentsURL = URL.documentsDirectory
          let fileName = "\(UUID().uuidString).usdz"
          let fileURL = documentsURL.appendingPathComponent(fileName)
          do {
              try finalResult.export(to: fileURL)
          } catch {
              print(error)
          }
      }
  }

Answer 1

Your code is a bit confusing.

• In terms of URL path is a file system string path, all your path variables are actually URLs.

• absoluteURL does nothing in this context, delete it.

• And the absoluteString detour is pointless, path.appendingPathComponent(c) is the URL you want, but with contentsOfDirectory(at:includingPropertiesForKeys:) you get full URLs for free.

  func saveFileLocal() {
        if let finalResult {
            let fm = FileManager.default
            let documentsURL = URL.documentsDirectory
            let fileName = "\(UUID().uuidString).usdz"
            let fileURL = documentsURL.appendingPathComponent(fileName)
            do {
                try finalResult.export(to: fileURL)
            } catch {
                print(error)
            }
        }
    }
  
   func removeFiles() {
        let fm = FileManager.default
        let documentsURL = URL.documentsDirectory
        do {
            let content = try fm.contentsOfDirectory(at: documentsURL, includingPropertiesForKeys: nil, options: .skipsHiddenFiles)
            for anURL in content {
                 try fm.removeItem(at: anURL)
            }
        } catch {
            print(error)
        }
    }
  

Answer 2

** Try starting your file name with a non-number** this workaround for this

Answer 3

File names for CapturedRoom export cannot start with a number - it's a leaky abstraction, implementation details about UDSZ have escaped and affect our choice of filenames.

If you'll change your implementation to:

if let testRoomCapture {
        let currentTimeInMilliseconds = CapturedRoomHelper().currentTimeInMiliseconds()
        let destinationFolderURL = FileManager.default.temporaryDirectory.appending(path: "Export")
        let destinationURL = destinationFolderURL.appending(path: "room_" + String(currentTimeInMilliseconds) + ".usdz")
        
        do {
            try testRoomCapture.export(to: destinationURL, exportOptions: .model)
            let fileManager = FileManager.default
            let fileExist = fileManager.fileExists(atPath: destinationURL.path())
            XCTAssertTrue(fileExist)
        } catch {
            print(error)
            XCTAssertNil(testRoomCapture, "Failed to export room data")
        }
    } else {
        XCTAssertNotNil(testRoomCapture, "Should have get a RoomCapture Object")
    }