/// <summary>
/// Handles a refresh operation by requesting routing data from peers
/// </summary>
/// <returns>The refresh operation.</returns>
/// <param name="selfinfo">The nodes own information.</param>
/// <param name="request">Request.</param>
/// <param name="k">The number of peers to request</param>
public static async Task HandleRefreshOperation(PeerInfo selfinfo, PeerRequest request, int k)
{
var res = await VisitClosestPeers(selfinfo, request.Key ?? selfinfo.Key, request.Key == null?k : 1, 1, new Protocol.Request()
{
Self = selfinfo,
Operation = Protocol.Operation.FindPeer,
Target = selfinfo.Key
});
if (request.Response != null)
{
await request.Response.WriteAsync(new PeerResponse()
{
SuccessCount = res.Count
});
}
}
/// <summary>
/// Handles a request to add a value to the DHT
/// </summary>
/// <returns>The add operation.</returns>
/// <param name="selfinfo">Selfinfo.</param>
/// <param name="request">The request to handle.</param>
/// <param name="k">The number of copies to store</param>
public static async Task HandleAddOperation(PeerInfo selfinfo, PeerRequest request, int k)
{
var key = Key.ComputeKey(request.Data);
log.Debug($"Handling the add request");
var stored = await VisitClosestPeers(selfinfo, key, k, k, new Protocol.Request()
{
Self = selfinfo,
Operation = Protocol.Operation.Store,
Data = request.Data,
Target = key
});
await request.Response.WriteAsync(new PeerResponse()
{
SuccessCount = stored.Count
});
}
/// <summary>
/// Handles the stats operation
/// </summary>
/// <returns>An awaitable task.</returns>
/// <param name="request">The request to handle.</param>
public static async Task HandleStatsOperation(PeerRequest request)
{
var brokerchan = Channel.Create <ConnectionStatsResponse>();
var mruchan = Channel.Create <MRUStatResponse>();
var routechan = Channel.Create <RoutingStatsResponse>();
var brokertask = Task.Run(brokerchan.ReadAsync);
var mrutask = Task.Run(mruchan.ReadAsync);
var routetask = Task.Run(routechan.ReadAsync);
// Send all requests
await Task.WhenAll(
Task.Run(() => Channels.ConnectionBrokerStats.Get().WriteAsync(brokerchan)),
Task.Run(() => Channels.MRUStats.Get().WriteAsync(mruchan)),
Task.Run(() => Channels.RoutingTableStats.Get().WriteAsync(routechan))
);
// Then wait for all results
await Task.WhenAll(
brokertask,
mrutask,
routetask
);
var sb = new StringBuilder();
foreach (var n in new object[] { await brokertask, await mrutask, await routetask })
{
sb.AppendLine(string.Format("{0}:", n.GetType().Name));
foreach (var p in n.GetType().GetFields(System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.DeclaredOnly | System.Reflection.BindingFlags.Instance))
{
sb.AppendLine(string.Format("{0}: {1}", p.Name, p.GetValue(n)));
}
}
await request.Response.WriteAsync(new PeerResponse()
{
Data = Encoding.UTF8.GetBytes(sb.ToString())
});
}
/// <summary>
/// Handles the find operation
/// </summary>
/// <returns>An awaitable task.</returns>
/// <param name="selfinfo">The nodes own information.</param>
/// <param name="request">The request to handle.</param>
/// <param name="k">The redundancy count</param>
public static async Task HandleFindOperation(PeerInfo selfinfo, PeerRequest request, int k)
{
// Query the local value store first
var data = await Channels.MRURequests.Get().SendGetAsync(request.Key);
if (data != null)
{
log.Debug($"Local lookup for key succeeded");
await request.Response.WriteAsync(new PeerResponse()
{
Data = data,
SuccessCount = 1
});
return;
}
var res = await VisitClosestPeers(selfinfo, request.Key, k, 1, new Protocol.Request()
{
Self = selfinfo,
Operation = Protocol.Operation.FindValue,
Target = request.Key
});
var result = res.Where(x => x.Success).FirstOrDefault();
if (result.Success)
{
log.Debug($"Lookup succeeded for key, (re-)adding to local table");
await Channels.MRURequests.Get().SendAddAsync(request.Key, result.Data);
}
await request.Response.WriteAsync(new PeerResponse()
{
Data = result.Data,
SuccessCount = res.Count
});
}
