public override int GetHashCode()
{
unchecked
{
return((LatestGossip.GetHashCode() * 397) ^ SelfUniqueAddress.GetHashCode());
}
}
public bool IsReachableExcludingDownedObservers(UniqueAddress toAddress)
{
if (!LatestGossip.HasMember(toAddress))
{
return(false);
}
// TODO: check for multiple DCs
return(LatestGossip.ReachabilityExcludingDownedObservers.Value.IsReachable(toAddress));
}
public bool Equals(MembershipState other)
{
if (ReferenceEquals(null, other))
{
return(false);
}
if (ReferenceEquals(this, other))
{
return(true);
}
return(SelfUniqueAddress.Equals(other.SelfUniqueAddress) && LatestGossip.Equals(other.LatestGossip));
}
/// <summary>
/// First check that:
/// 1. we don't have any members that are unreachable, or
/// 2. all unreachable members in the set have status DOWN or EXITING
/// Else we can't continue to check for convergence. When that is done
/// we check that all members with a convergence status is in the seen
/// table and has the latest vector clock version.
/// </summary>
/// <param name="exitingConfirmed">The set of nodes who have been confirmed to be exiting.</param>
/// <returns><c>true</c> if convergence has been achieved. <c>false</c> otherwise.</returns>
public bool Convergence(IImmutableSet <UniqueAddress> exitingConfirmed)
{
// If another member in the data center that is UP or LEAVING
// and has not seen this gossip or is exiting
// convergence cannot be reached
bool MemberHinderingConvergenceExists()
{
return(Members.Any(x => ConvergenceMemberStatus.Contains(x.Status) &&
!(LatestGossip.SeenByNode(x.UniqueAddress) ||
exitingConfirmed.Contains(x.UniqueAddress))));
}
// Find cluster members in the data center that are unreachable from other members of the data center
// excluding observations from members outside of the data center, that have status DOWN or is passed in as confirmed exiting.
var unreachable = DcReachabilityExcludingDownedObservers.AllUnreachableOrTerminated
.Where(node => node != SelfUniqueAddress && !exitingConfirmed.Contains(node))
.Select(x => LatestGossip.GetMember(x));
// unreachables outside of the data center or with status DOWN or EXITING does not affect convergence
var allUnreachablesCanBeIgnored =
unreachable.All(m => ConvergenceSkipUnreachableWithMemberStatus.Contains(m.Status));
return(allUnreachablesCanBeIgnored && !MemberHinderingConvergenceExists());
}
/// <summary> /// Copies the current <see cref="MembershipState"/> and marks the <see cref="LatestGossip"/> as Seen /// by the <see cref="SelfUniqueAddress"/>. /// </summary> /// <returns>A new <see cref="MembershipState"/> instance with the updated seen records.</returns> public MembershipState Seen() => Copy(LatestGossip.Seen(SelfUniqueAddress));
