Consider APIs for dealing with CallEvents when there are variable failures

[yschimke]

I wonder how many other users will get impacted by this?!

Originally posted by @swankjesse in #9515

[Swapnendu003]

Here is what seems to be going wrong and why.

What is happening
The investigation chain stops at Android API behavior change, but the true root cause is OkHttp's fragile exception handling patterns that catch specific exception types directly rather than checking exception chains

1. Why was issue Consider APIs for dealing with CallEvents when there are variable failures #9534 created?
   @swankjesse expressed concern about user impact from changes handling failed connection attempts in dual-stack loopback environments
   Evidence: GitHub issue Consider APIs for dealing with CallEvents when there are variable failures #9534 body contains quoted concern
2. Why was there concern about user impact?
   Android API 37 introduces behavioral changes where SSLPeerUnverifiedException is wrapped as a cause rather than thrown directly
   Evidence: GitHub issue Investigate SSLPeerUnverifiedException changes in Android 37 #9535 title and body mention SSLPeerUnverifiedException changes in Android 37
3. Why does this behavioral change matter? (unproven — evidence ends here)
   OkHttp's error handling in multiple places catches SSLPeerUnverifiedException directly and may not handle wrapped exceptions
   Evidence: GitHub issue Investigate SSLPeerUnverifiedException changes in Android 37 #9535 lists SSLSession.handshake(), RealConnection.isEligible(), RetryAndFollowUpInterceptor.isRecoverable(), retryTlsHandshake()

Not confirmed: The deepest proven link (Android API change) is a symptom, not a root cause. Fixing only the Android behavior wouldn't prevent similar issues from other platform changes. The true root cause would be OkHttp's fragile exception handling patterns, but this cannot be verified without access to the codebase to examine the cited locations.

This is a starting point, not a final answer. Please check it against the actual code and behaviour before relying on it.

I put this together with Operate (https://operatex.dev), an AI tool that reads the code and traces the likely cause, and reviewed it before posting.