Workaround for query-consistency-strong which is presently partially …

…broken (#5928)

Provides a workaround for query-consistency-strong which is presently partially broken.

common/client/versionChecker.go

@@ -209,6 +209,7 @@ func (vc *versionChecker) SupportsStickyQuery(clientImpl string, clientFeatureVe
 // SupportsConsistentQuery returns error if consistent query is not supported otherwise nil.
 // In case client version lookup fails assume the client does not support feature.
 func (vc *versionChecker) SupportsConsistentQuery(clientImpl string, clientFeatureVersion string) error {
+
 	return vc.featureSupported(clientImpl, clientFeatureVersion, consistentQuery)
 }
 

service/history/decision/handler.go

@@ -725,7 +725,15 @@ func (handler *handlerImpl) handleBufferedQueries(
 
 	// Consistent query requires both server and client worker support. If a consistent query was requested (meaning there are
 	// buffered queries) but worker does not support consistent query then all buffered queries should be failed.
-	if versionErr := handler.versionChecker.SupportsConsistentQuery(clientImpl, clientFeatureVersion); versionErr != nil {
+	versionErr := handler.versionChecker.SupportsConsistentQuery(clientImpl, clientFeatureVersion)
+	// todo (David.Porter) remove the skip on version check for
+	// clientImpl and clientFeatureVersion where they're nil
+	// There's a bug, probably in matching somewhere which isn't
+	// forwarding the client headers for version
+	// info correctly making this call erroneously fail sometimes.
+	// https://t3.uberinternal.com/browse/CDNC-8641
+	// So defaulting just this flow to fail-open in the absence of headers.
+	if versionErr != nil && clientImpl != "" && clientFeatureVersion != "" {
 		scope.IncCounter(metrics.WorkerNotSupportsConsistentQueryCount)
 		failedTerminationState := &query.TerminationState{
 			TerminationType: query.TerminationTypeFailed,