UI Hang Risk: Synchronous File Reading on Main Thread

[ahmdmhasn]

Summary

Xcode's Thread Sanitizer warns about potential UI hangs due to synchronous file reading on the main thread in PersistentStorage.swift. This issue is highlighted by Xcode's known hang system, which suggests migrating away from String(contentsOf:, encoding:).

Expected Behavior

No warnings should be present, and file reading operations should not risk UI hangs.

Current Behavior

Xcode displays a warning for potential UI hangs and suggests an enhancement to the code.

Specific Location

File: PersistentStorage.swift

func getEventsString(eventBlock: EventBlock) -> String? {
    ...
    content = try String(contentsOf: eventBlock, encoding: .utf8) // <-- Warning shown here
    ...
}

Possible Solution

Use url.absoluteString instead

Steps to Reproduce

1. Open the project in Xcode.
2. Build the project using Amplitude SDK.
3. Navigate to PersistentStorage.swift.
4. Locate the getEventsString(eventBlock:) function.
5. Observe the warning on the line using String(contentsOf:, encoding:).

Environment

• Amplitude: 1.4.5
• SDK Version: iOS 17.5
• Device: iPhone 15
• OS Version: macOS 14.5 (23F79)
• Xcode: 15.4

[crleona]

@ahmdmhasn which version of the Amplitude SDK are you using?

[ahmdmhasn]

@crleona Amplitude 1.4.5

[crleona]

@ahmdmhasn - you appear to be using an outdated version of https://github.com/amplitude/Amplitude-Swift, not https://github.com/amplitude/Amplitude-iOS. Please update.