public bool?Update(DateTime utcNow, long counter, bool simulateFailure)
{
bool?result = null;
PeerGroup peerGroup = this.Location.PeerGroup;
if (peerGroup.CanPoll(utcNow, this.lastPolled))
{
bool?wasConnected = this.IsConnected;
using (Pinger pinger = new Pinger(peerGroup.Wait))
{
TimeSpan roundtripTime = TimeSpan.Zero;
this.IsConnected = !simulateFailure && pinger.TryPing(this.Location.Address, out roundtripTime);
this.RoundtripTime = roundtripTime;
this.UpdateCounter = counter;
}
result = this.IsConnected != wasConnected;
this.lastPolled = utcNow;
}
return(result);
}
private bool FindPeerGroupState(PeerGroup peerGroup, out PeerGroupState state)
{
state = this.PeerGroups.FirstOrDefault(s => s.PeerGroup == peerGroup);
return(state != null);
}
private void PeerGroupsCollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
List <Location> toRemove = null;
switch (e.Action)
{
case NotifyCollectionChangedAction.Remove:
// Remove any locations using the removed peer groups. The UI should prevent this from occurring.
IEnumerable <PeerGroup> oldItems = e.OldItems.Cast <PeerGroup>();
toRemove = new List <Location>();
foreach (Location location in this.Locations.Where(l => oldItems.Any(g => g == l.PeerGroup)))
{
toRemove.Add(location);
}
break;
case NotifyCollectionChangedAction.Replace:
// Replace any locations that are using the replaced peer groups.
oldItems = e.OldItems.Cast <PeerGroup>();
IEnumerable <PeerGroup> newItems = e.NewItems.Cast <PeerGroup>();
var pairs = oldItems.Zip(newItems, (o, n) => Tuple.Create(o, n)).ToArray();
int numLocations = this.Locations.Count;
for (int i = 0; i < numLocations; i++)
{
Location currentLocation = this.Locations[i];
PeerGroup replacement = pairs.FirstOrDefault(p => p.Item1 == currentLocation.PeerGroup)?.Item2;
if (replacement != null)
{
this.Locations[i] = new Location(replacement, currentLocation.Name, currentLocation.Address, currentLocation.Id);
}
}
break;
case NotifyCollectionChangedAction.Reset:
// Update all locations. Use latest peer group with matching Id. Delete non-matches.
numLocations = this.Locations.Count;
var idToGroupMap = this.PeerGroups.ToDictionary(g => g.Id);
toRemove = new List <Location>();
for (int i = 0; i < numLocations; i++)
{
Location currentLocation = this.Locations[i];
if (idToGroupMap.TryGetValue(currentLocation.PeerGroup.Id, out PeerGroup replacement))
{
this.Locations[i] = new Location(replacement, currentLocation.Name, currentLocation.Address, currentLocation.Id);
}
else
{
toRemove.Add(currentLocation);
}
}
break;
}
foreach (Location location in toRemove ?? Enumerable.Empty <Location>())
{
this.Locations.Remove(location);
}
}
private void LoadDefaults()
{
void AddLocation(Location location)
{
// Don't add a duplicate address (e.g., both router and modem if they're the same).
if (!this.Locations.Any(l => l.Address.Equals(location.Address)))
{
if (!this.PeerGroups.Contains(location.PeerGroup))
{
this.PeerGroups.Add(location.PeerGroup);
}
this.Locations.Add(location);
}
}
XElement root = XElement.Parse(Properties.Resources.DefaultProfileXml);
foreach (XElement groupElement in root.Elements(nameof(PeerGroup)))
{
string groupName = groupElement.GetAttributeValue("Name");
#pragma warning disable MEN010 // Avoid magic numbers. Default times are clear in context.
int failSeconds = groupElement.GetAttributeValue("FailSeconds", 10);
int pollSeconds = groupElement.GetAttributeValue("PollSeconds", 5);
int waitMilliseconds = groupElement.GetAttributeValue("WaitMilliseconds", 200);
#pragma warning restore MEN010 // Avoid magic numbers
PeerGroup group = new PeerGroup(
groupName,
TimeSpan.FromSeconds(failSeconds),
TimeSpan.FromSeconds(pollSeconds),
TimeSpan.FromMilliseconds(waitMilliseconds));
foreach (XElement locationElement in groupElement.Elements(nameof(Location)))
{
string locationName = locationElement.GetAttributeValue("Name");
int ordinal = 1;
foreach (XElement addressElement in locationElement.Elements("Address"))
{
if (IPAddress.TryParse(addressElement.Value, out IPAddress address))
{
string nameSuffix = ordinal == 1 ? string.Empty : $" #{ordinal}";
Location location = new Location(group, locationName + nameSuffix, address);
AddLocation(location);
ordinal++;
}
}
}
foreach (XElement findElement in groupElement.Elements("Find"))
{
string findName = findElement.GetAttributeValue("Name");
string findType = findElement.GetAttributeValue("Type");
IPAddress address;
switch (findType)
{
case "DefaultGateway":
// The first IP address returned by a traceroute should be the gateway. https://stackoverflow.com/a/29494180/1882616
// We'll simulate that by doing a ping with TTL = 1. https://stackoverflow.com/a/45565253/1882616
address = Pinger.GetAddressAtTtl(IPAddress.Parse("8.8.8.8"), 1, group.Wait);
break;
case "CableModem":
using (Pinger pinger = new Pinger(group.Wait))
{
address = findElement.Elements("Address").Select(e => IPAddress.Parse(e.Value)).FirstOrDefault(a => pinger.TryPing(a) ?? false);
}
break;
default:
throw Exceptions.NewInvalidOperationException($"Unsupported Find Type: {findType}");
}
if (address != null)
{
Location location = new Location(group, findName, address);
AddLocation(location);
}
}
}
}
internal PeerGroupState(PeerGroup peerGroup)
{
this.PeerGroup = peerGroup;
this.UpdateCounter = -1;
}