log context cancellation reasons

[apesternikov]

It is hard to debug a test failure caused by finished context. Possible reasons are:

• timeout
• signal
• stdin closed
• error watching k8s events
  Better logging of the reason for context cancellation should help in this case.

[codereviewbot-ai]

The context.WithTimeoutCause and context.WithCancelCause functions do not exist in the standard Go context package. This could lead to compilation errors if these are not custom implementations. If these are custom implementations, it's recommended to ensure they are well-documented and tested, considering the critical nature of context handling in concurrent Go applications. If they are intended to be the standard context.WithTimeout and context.WithCancel, replacing them with the correct functions from the standard library is advised to avoid confusion and potential runtime issues.

[codereviewbot-ai]

Cancelling the context with an error message constructed using fmt.Errorf inside a deferred function that runs in a goroutine can lead to a race condition where the main function may exit before the deferred function has a chance to cancel the context. This can result in the error message not being logged or acted upon as intended. A more reliable approach would be to ensure that all goroutines have completed their execution and any necessary context cancellation has been performed before allowing the main function to exit. This might involve using synchronization primitives like sync.WaitGroup to wait for goroutines to finish their execution.

[codereviewbot-ai]

The error handling logic in the goroutine that reads from os.Stdin checks if the error is io.EOF using a redundant condition. The condition err != nil && err == io.EOF can be simplified to just err == io.EOF since err == io.EOF implicitly covers the case where err is not nil. Simplifying this condition will improve the readability of the code without changing its functionality.