@ -24,6 +24,7 @@ import (
)
const minHeartbeatInterval = 500 * time . Millisecond
const wireVersion42 = 8 // Wire version for MongoDB 4.2
// Server state constants.
const (
@ -294,6 +295,8 @@ func (s *Server) ProcessHandshakeError(err error, startingGenerationNumber uint6
return
}
// Unwrap any connection errors. If there is no wrapped connection error, then the error should
// not result in any Server state change (e.g. a command error from the database).
wrappedConnErr := unwrapConnectionError ( err )
if wrappedConnErr == nil {
return
@ -384,27 +387,58 @@ func getWriteConcernErrorForProcessing(err error) (*driver.WriteConcernError, bo
// ProcessError handles SDAM error handling and implements driver.ErrorProcessor.
func ( s * Server ) ProcessError ( err error , conn driver . Connection ) driver . ProcessErrorResult {
// ignore nil error
// Ignore nil errors.
if err == nil {
return driver . NoChange
}
// Ignore errors from stale connections because the error came from a previous generation of the
// connection pool. The root cause of the error has aleady been handled, which is what caused
// the pool generation to increment. Processing errors for stale connections could result in
// handling the same error root cause multiple times (e.g. a temporary network interrupt causing
// all connections to the same server to return errors).
if conn . Stale ( ) {
return driver . NoChange
}
// Must hold the processErrorLock while updating the server description and clearing the pool.
// Not holding the lock leads to possible out-of-order processing of pool.clear() and
// pool.ready() calls from concurrent server description updates.
s . processErrorLock . Lock ( )
defer s . processErrorLock . Unlock ( )
// ignore stale error
if conn . Stale ( ) {
return driver . NoChange
// Get the wire version and service ID from the connection description because they will never
// change for the lifetime of a connection and can possibly be different between connections to
// the same server.
connDesc := conn . Description ( )
wireVersion := connDesc . WireVersion
serviceID := connDesc . ServiceID
// Get the topology version from the Server description because the Server description is
// updated by heartbeats and errors, so typically has a more up-to-date topology version.
serverDesc := s . desc . Load ( ) . ( description . Server )
topologyVersion := serverDesc . TopologyVersion
// We don't currently update the Server topology version when we create new application
// connections, so it's possible for a connection's topology version to be newer than the
// Server's topology version. Pick the "newest" of the two topology versions.
// Technically a nil topology version on a new database response should be considered a new
// topology version and replace the Server's topology version. However, we don't know if the
// connection's topology version is based on a new or old database response, so we ignore a nil
// topology version on the connection for now.
//
// TODO(GODRIVER-2841): Remove this logic once we set the Server description when we create
// TODO application connections because then the Server's topology version will always be the
// TODO latest known.
if tv := connDesc . TopologyVersion ; tv != nil && topologyVersion . CompareToIncoming ( tv ) < 0 {
topologyVersion = tv
}
// Invalidate server description if not primary or node recovering error occurs.
// These errors can be reported as a command error or a write concern error.
desc := conn . Description ( )
if cerr , ok := err . ( driver . Error ) ; ok && ( cerr . NodeIsRecovering ( ) || cerr . NotPrimary ( ) ) {
// ignore stale error
if desc . TopologyVersion . CompareToIncoming ( cerr . TopologyVersion ) >= 0 {
// Ignore errors that came from when the database was on a previous topology version.
if t opologyVersion. CompareToIncoming ( cerr . TopologyVersion ) >= 0 {
return driver . NoChange
}
@ -414,16 +448,16 @@ func (s *Server) ProcessError(err error, conn driver.Connection) driver.ProcessE
res := driver . ServerMarkedUnknown
// If the node is shutting down or is older than 4.2, we synchronously clear the pool
if cerr . NodeIsShuttingDown ( ) || desc. WireVersion == nil || desc . WireVersion . Max < 8 {
if cerr . NodeIsShuttingDown ( ) || wireVersion == nil || wireVersion . Max < wireVersion42 {
res = driver . ConnectionPoolCleared
s . pool . clear ( err , de sc. S erviceID)
s . pool . clear ( err , )
}
return res
}
if wcerr , ok := getWriteConcernErrorForProcessing ( err ) ; ok {
// ignore stale error
if desc. T opologyVersion. CompareToIncoming ( wcerr . TopologyVersion ) >= 0 {
// Ignore errors that came from when the database was on a previous topology version.
if t opologyVersion. CompareToIncoming ( wcerr . TopologyVersion ) >= 0 {
return driver . NoChange
}
@ -433,9 +467,9 @@ func (s *Server) ProcessError(err error, conn driver.Connection) driver.ProcessE
res := driver . ServerMarkedUnknown
// If the node is shutting down or is older than 4.2, we synchronously clear the pool
if wcerr . NodeIsShuttingDown ( ) || desc. WireVersion == nil || desc . WireVersion . Max < 8 {
if wcerr . NodeIsShuttingDown ( ) || wireVersion == nil || wireVersion . Max < wireVersion42 {
res = driver . ConnectionPoolCleared
s . pool . clear ( err , de sc. S erviceID)
s . pool . clear ( err , )
}
return res
}
@ -457,7 +491,7 @@ func (s *Server) ProcessError(err error, conn driver.Connection) driver.ProcessE
// monitoring check. The check is cancelled last to avoid a post-cancellation reconnect racing with
// updateDescription.
s . updateDescription ( description . NewServerFromError ( s . address , err , nil ) )
s . pool . clear ( err , de sc. S erviceID)
s . pool . clear ( err , )
s . cancelCheck ( )
return driver . ConnectionPoolCleared
}
