After SocketTimeoutException, request is retried with different TLS mode

[efung]

When I set a connect timeout on OkHttpClient and attempt to reach an HTTPS endpoint that throws a SocketTimeoutException, OkHttp is retrying the request once before giving up. This is what I believe is happening:

• Upon the initial timeout exception, HttpURLConnectionImpl.handleFailure() adds the failed route (with TLS_MODE_MODERN flag) to the RouteDatabase. The database also adds the route with TLS_MODE_COMPATIBLE since it wasn't a handshake exception.
• handleFailure() checks to see if the error is recoverable. The test routeSelector.hasNext() returns true, since RouteSelector.hasNextTlsMode() returns true. Another engine is created to try again.
• The next time through, the route matches a failed route in the RouteDatabase and is added to the set of postponed routes, and is eventually tried again.
• After this attempt fails with a SocketTimeoutException, there are no more TLS modes, addresses, proxies or postponed routes to try, so the RouteSelector will return null, and HttpURLConnectionImpl returns with a permanent failure.

I would expect that a route is tried again with the fallback TLS behaviour, only if there was a handshake exception, and not when a SocketTimeoutException is encountered.

I'm using OkHttp 1.3.0 on Android 4.2.2.

[swankjesse]

Yup, great investigation. There's a disconnect between hasNext() and failed TLS modes. We need to tell the route selector that neither TLS mode will work for this host.

[swankjesse]

Fixed. Thanks for the helpful report!