commit 8087fb47ef39a212c7d839b6785786b4e6428ddc
from: Stephen J Day <stephen.day@docker.com>
date: Thu May 19 00:56:05 2016 UTC

client: log messages with unknown tags

Several clients have experienced panics after receiving unknown tags.
The exact cause of these unknown messages is unknown. It is also not
clear whether an unknown tag should be fatal to the session.

This change provides more information in the panic message which we can
then use to better understand this condition.

Signed-off-by: Stephen J Day <stephen.day@docker.com>

commit - e4e59ce7912b9968a48881a7764fc501de667cd4
commit + 8087fb47ef39a212c7d839b6785786b4e6428ddc
blob - 955fe76c6b5dd784b27c69d2accec8ae0a264db7
blob + 8a19e3836a0154314bf8f609fbf91e0ea0a29314
--- transport.go
+++ transport.go
@@ -170,7 +170,12 @@ func (t *transport) handle() {
 		case b := <-responses:
 			req, ok := outstanding[b.Tag]
 			if !ok {
-				panic("unknown tag received")
+				// BUG(stevvooe): The exact handling of an unknown tag is
+				// unclear at this point. These may not necessarily fatal to
+				// the session, since they could be messages that the client no
+				// longer cares for. When we figure this out, replace this
+				// panic with something more sensible.
+				panic(fmt.Sprintf("unknown tag received: %v", b))
 			}
 
 			// BUG(stevvooe): Must detect duplicate tag and ensure that we are