Esempio n. 1
0
        /// <summary>
        /// Adds a peer to the routing table
        /// </summary>
        /// <returns><c>true</c> if the item was added; <c>false</c> otherwise.</returns>
        /// <param name="peer">Peer.</param>
        /// <param name="isNew">A flag indicating if the item was new</param>
        public bool Add(PeerInfo peer, out bool isNew)
        {
            if (peer == null)
            {
                throw new ArgumentNullException(nameof(peer));
            }

            isNew = false;

            // Get the closest leaf node
            var node = GetClosestLeaf(peer.Key);

            // Check if we are re-inserting a known key
            for (var i = 0; i < node.Items.Count; i++)
            {
                if (node.Items[i].Key.Equals(peer.Key))
                {
                    // Are we simply re-freshing the peer?
                    if (node.Items[i].Address.Equals(peer.Address))
                    {
                        // Refreshing, move the item to the top
                        node.Items.RemoveAt(i);
                        node.Items.Add(peer);
                        return(true);
                    }

                    // We are not replacing keys
                    return(false);
                }
            }

            // Keep splitting until we have space
            while (true)
            {
                // Do we have space?
                if (node.Items.Count == m_k)
                {
                    // No space, but should we make space?
                    if (PrefixMatches(node, peer.Key) || node == m_root)
                    {
                        SplitNode(node);
                        node = PrefixMatches(node, peer.Key) ? node.Right : node.Left;
                        continue;
                    }

                    // No more space
                    return(false);
                }


                // We have space, so just add it
                node.Items.Add(peer);
                m_count++;
                isNew = true;
                return(true);
            }
        }
Esempio n. 2
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        /// <summary>
        /// Listens to the socket and registers all new requests
        /// </summary>
        /// <returns>The async.</returns>
        /// <param name="selfinfo">Selfinfo.</param>
        /// <param name="sock">Sock.</param>
        private static Task ListenAsync(PeerInfo selfinfo, TcpListener sock)
        {
            // Set up a channel for sending sockets
            var sockchan = Channel.Create <TcpClient>();
            var listener = Task.Run(async() =>
            {
                while (true)
                {
                    await sockchan.WriteAsync(await sock.AcceptTcpClientAsync());
                }
            });

            // Handle each request
            var handlers = Skeletons.CollectAsync(sockchan, async client => {
                var peer = PeerConnection.CreatePeer(selfinfo, selfinfo, client.GetStream());

                // Ping the peer
                var res = await peer.Item2.SendConnectionRequestAsync(null, null,
                                                                      new Protocol.Request()
                {
                    Operation = Protocol.Operation.Ping,
                    Self      = selfinfo,
                });

                // Register this peer with the broker
                await Channels.ConnectionBrokerRegistrations.Get().WriteAsync(
                    new ConnectionRegistrationRequest()
                {
                    IsTerminate   = false,
                    UpdateRouting = true,
                    Peer          = res.Response.Self,
                    Channel       = peer.Item2
                }
                    );

                // If we get anything back, register with the routing table
                if (res.Response.Peers != null)
                {
                    var router = Channels.RoutingTableRequests.Get();

                    log.Debug($"Ping response had {res.Response.Peers.Count} peers, registering with routing table");
                    foreach (var np in res.Response.Peers)
                    {
                        await router.AddPeerAsync(np.Key, np);
                    }
                }

                log.Debug("Completed initial ping sequence");
            }, 10);

            return(Task.WhenAll(listener, handlers));
        }
Esempio n. 3
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        /// <summary>
        /// Handles a remote ping request
        /// </summary>
        /// <returns>An awaitable task.</returns>
        /// <param name="self">The node information.</param>
        /// <param name="req">The request to handle.</param>
        private static Task HandlePingRequestAsync(PeerInfo self, ConnectionRequest req)
        {
            log.Debug($"Converting ping request to node lookup ({req.RequestID})");

            return(HandleNodeLookupRequestAsync(self, new ConnectionRequest()
            {
                Key = self.Key,
                EndPoint = self.Address,
                RequestID = req.RequestID,
                Response = req.Response,
                Request = new Protocol.Request()
                {
                    Target = self.Key,
                    Operation = Protocol.Operation.Ping
                }
            }));
        }
Esempio n. 4
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        /// <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
                });
            }
        }
Esempio n. 5
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        /// <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
            });
        }
Esempio n. 6
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        /// <summary>
        /// Handles a remote store request
        /// </summary>
        /// <returns>An awaitable task.</returns>
        /// <param name="self">The node information.</param>
        /// <param name="request">The request to handle.</param>
        private static async Task HandleStoreRequestAsync(PeerInfo self, ConnectionRequest request)
        {
            log.Debug($"Query MRU ({request.RequestID})");
            var res = await Channels.MRURequests.Get()
                      .SendAddAsync(request.Request.Target, request.Request.Data);

            log.Debug($"Got response, forwarding to requester ({request.RequestID}) ...");
            await request.Response.WriteAsync(new ConnectionResponse()
            {
                RequestID = request.RequestID,
                Response  = new Protocol.Response()
                {
                    Self    = self,
                    Success = res,
                }
            });

            log.Debug($"Completed store query ({request.RequestID})");
        }
Esempio n. 7
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        /// <summary>
        /// Runs the discovery process
        /// </summary>
        /// <returns>An awaitable task.</returns>
        /// <param name="self">The peer making the query.</param>
        /// <param name="endPoints">The end points to query.</param>
        public static Task RunAsync(PeerInfo self, EndPoint[] endPoints)
        {
            if (self == null)
            {
                throw new ArgumentNullException(nameof(self));
            }
            if (endPoints == null)
            {
                throw new ArgumentNullException(nameof(endPoints));
            }

            var targets = endPoints.Where(x => !self.Address.Equals(x));

            log.Debug($"Performing discovery on {targets.Count()} peer");
            return(TaskPool.RunParallelAsync(
                       targets,
                       x => QueryPeerAsync(self, x),
                       (x, ex) => log.Warn($"Discovery failed for peer {x}", ex)
                       ).ContinueWith(x => log.Debug("Discovery process completed")));
        }
Esempio n. 8
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        /// <summary>
        /// Broadcasts the store operation to the peers.
        /// </summary>
        /// <returns>An awaitable task.</returns>
        /// <param name="request">The internal request to handle.</param>
        private static async Task BroadcastValueAsync(PeerInfo self, MRUInternalStore request)
        {
            log.Debug($"Broadcasting store to {request.Peers.Count - 1} peers");

            var tp = new TaskPool <PeerInfo>(5, (x, ex) => log.Warn($"Failed to broadcast to peer {x.Key} - {x.Address}", ex));
            var cb = Channels.ConnectionBrokerRequests.Get();

            foreach (var n in request.Peers.Where(x => !self.Key.Equals(x.Key)))
            {
                // Send a store request to all the k nearest peers
                await tp.Run(n, peer => cb.SendConnectionRequestAsync(peer.Address, peer.Key,
                                                                      new Protocol.Request()
                {
                    Operation = Protocol.Operation.Store,
                    Data      = request.Data,
                    Target    = request.Key,
                    Self      = self
                }
                                                                      ));
            }
        }
Esempio n. 9
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        /// <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
            });
        }
Esempio n. 10
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        /// <summary>
        /// Queries a single peer, trying to obtain the peer information and updates the routing table
        /// </summary>
        /// <returns>An awaitable task.</returns>
        /// <param name="self">The peer making the query.</param>
        /// <param name="endPoint">The end point to query.</param>
        private static async Task QueryPeerAsync(PeerInfo self, EndPoint endPoint)
        {
            if (self == null)
            {
                throw new ArgumentNullException(nameof(self));
            }
            if (endPoint == null)
            {
                throw new ArgumentNullException(nameof(endPoint));
            }

            if (!(endPoint is IPEndPoint))
            {
                throw new ArgumentException($"Can only connect to an {nameof(IPEndPoint)}", nameof(endPoint));
            }

            log.Debug($"Performing discovery on {endPoint} ...");

            var response = await Channels.ConnectionBrokerRequests.Get().SendConnectionRequestAsync(endPoint, null,
                                                                                                    new Protocol.Request()
            {
                Self      = self,
                Operation = Protocol.Operation.FindPeer,
                Target    = self.Key
            });

            log.Debug($"Discovery response arrived from {endPoint} ...");

            if (response.Exception != null)
            {
                log.DebugFormat("Failed to contact peer {0}: {1}", endPoint, response.Exception);
                return;
            }

            log.Debug($"Discovery complete for {endPoint}");
        }
Esempio n. 11
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        /// <summary>
        /// Creates a new peer for the given endpoint
        /// </summary>
        /// <returns>A task for the peer, and a communication channel.</returns>
        /// <param name="self">This peer's information</param>
        /// <param name="remote">The remote peer's information</param>
        /// <param name="connecthandler">The method used to obtain the stream</param>
        /// <param name="maxparallel">The maximum number of requests to handle in parallel</param>
        public static Tuple <Task, IWriteChannel <ConnectionRequest> > CreatePeer(PeerInfo self, PeerInfo remote, Func <Task <Stream> > connecthandler, int maxparallel = REQ_BUFFER_SIZE)
        {
            if (self == null)
            {
                throw new ArgumentNullException(nameof(self));
            }
            if (connecthandler == null)
            {
                throw new ArgumentNullException(nameof(connecthandler));
            }

            var source = Channel.Create <ConnectionRequest>();
            var sink   = Channel.Create <ConnectionRequest>();

            return(new Tuple <Task, IWriteChannel <ConnectionRequest> >(
                       Task.WhenAll(
                           Task.Run(() => RunSingleConnection(self, remote, connecthandler, sink.AsRead(), maxparallel)),
                           TaskPool.RunParallelAsync(
                               source.AsRead(),
                               x => sink.WriteAsync(x),
                               REQ_BUFFER_SIZE,
                               async(c, x) =>
            {
                try { await c.Response.WriteAsync(new ConnectionResponse()
                    {
                        Exception = x
                    }); }
                catch (Exception ex) { log.Warn("Failed to send error response", ex); }
            }
                               )
                           ),
                       source.AsWrite()
                       ));
        }
Esempio n. 12
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 /// <summary>
 /// Creates a new peer for the given endpoint
 /// </summary>
 /// <returns>A task for the peer, and a communication channel.</returns>
 /// <param name="self">This peer's information</param>
 /// <param name="remote">The remote peer's information</param>
 /// <param name="stream">The stream to use.</param>
 /// <param name="maxparallel">The maximum number of requests to handle in parallel</param>
 public static Tuple <Task, IWriteChannel <ConnectionRequest> > CreatePeer(PeerInfo self, PeerInfo remote, Stream stream, int maxparallel = REQ_BUFFER_SIZE)
 {
     return(CreatePeer(self, remote, () => Task.FromResult(stream), maxparallel));
 }
Esempio n. 13
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        /// <summary>
        /// Runs the broker process.
        /// </summary>
        /// <param name="node">This nodes information</param>
        /// <param name="maxconnections">The maximum number of connections to allow</param>
        /// <returns>An awaitable task.</returns>
        public static Task RunAsync(PeerInfo node, int maxconnections = 50)
        {
            // The primary table for finding peers
            var peers = new Dictionary <EndPoint, Tuple <Task, IWriteChannel <ConnectionRequest> > >();

            // The peers listed by key
            var peersbykey = new Dictionary <Key, EndPoint>();

            // The MRU cache of peers
            var mrucache = new MRUCache <EndPoint, Key>(maxconnections, TimeSpan.FromDays(10));

            return(AutomationExtensions.RunTask(
                       new
            {
                Request = Channels.ConnectionBrokerRequests.ForRead,
                Registrations = Channels.ConnectionBrokerRegistrations.ForRead,
                Stats = Channels.ConnectionBrokerStats.ForRead,
                SelfHandler = Channels.RemoteRequests.ForWrite,
                Routing = Channels.RoutingTableRequests.ForWrite
            },

                       async self =>
            {
                log.Debug($"Broker is now running");
                while (true)
                {
                    log.Debug($"Broker is waiting for requests ...");
                    var mreq = await MultiChannelAccess.ReadFromAnyAsync(
                        self.Stats.RequestRead(),
                        self.Registrations.RequestRead(),
                        self.Request.RequestRead()
                        );

                    if (mreq.Channel == self.Stats)
                    {
                        log.Debug($"Broker got stat request");
                        var req = (IWriteChannel <ConnectionStatsResponse>)mreq.Value;
                        await req.WriteAsync(new ConnectionStatsResponse()
                        {
                            EndPoints = peers.Count,
                            Keys = peersbykey.Count,
                            Stats = (Channels.ConnectionBrokerRequests.Get() as ProfilingChannel <ConnectionRequest>)?.ReportStats()
                        });
                    }
                    else if (mreq.Channel == self.Registrations)
                    {
                        var req = (ConnectionRegistrationRequest)mreq.Value;
                        log.Debug($"Broker got {(req.IsTerminate ? "termination" : "registration")} request");
                        if (req.IsTerminate)
                        {
                            // Make sure we do not have stale stuff in the MRU cache
                            if (req.Peer != null && req.Peer.Address != null)
                            {
                                mrucache.Remove(req.Peer.Address);
                            }

                            if (req.Peer.Address != null && peers.TryGetValue(req.Peer.Address, out var c) && c.Item2 == req.Channel)
                            {
                                peers.Remove(req.Peer.Address);
                                if (req.Peer.Key != null)
                                {
                                    peersbykey.Remove(req.Peer.Key);
                                }
                            }

                            if (req.UpdateRouting)
                            {
                                log.Debug($"Removing peer in routing table due to termination of connection {req.Peer.Key} - {req.Peer.Address}");
                                await self.Routing.RemovePeerAsync(req.Peer.Key);
                            }
                        }
                        else
                        {
                            if (req.Peer.Address != null && peers.TryGetValue(req.Peer.Address, out var c) && (c.Item2 == req.Channel || c == null))
                            {
                                if (c == null)
                                {
                                    peers[req.Peer.Address] = new Tuple <Task, IWriteChannel <ConnectionRequest> >(null, req.Channel);
                                }

                                if (!peersbykey.ContainsKey(req.Peer.Key))
                                {
                                    peersbykey[req.Peer.Key] = req.Peer.Address;
                                }
                            }

                            if (req.UpdateRouting)
                            {
                                log.Debug($"Adding new peer to routing table {req.Peer.Key} - {req.Peer.Address}");
                                await self.Routing.AddPeerAsync(req.Peer.Key, req.Peer);
                            }
                        }
                    }
                    else
                    {
                        var req = (ConnectionRequest)mreq.Value;
                        log.Debug($"Broker got connection request for {req.EndPoint}");

                        // Check if we request ourselves
                        if (node.Key.Equals(req.Key) || node.Address.Equals(req.EndPoint))
                        {
                            log.Debug($"Broker got self-request, forwarding to owner");
                            await self.SelfHandler.WriteAsync(req);
                            continue;
                        }

                        Tuple <Task, IWriteChannel <ConnectionRequest> > peer = null;
                        try
                        {
                            // Existing connection, update MRU
                            var overflow = mrucache.Add(req.EndPoint, req.Key);

                            // If we have too many connections, kill one now
                            if (overflow != null)
                            {
                                // We could make this also take the closest k peers into account
                                log.Debug($"Broker has too many connections, closing {req.EndPoint}");
                                await peers[overflow].Item2.RetireAsync();
                            }

                            if (!peers.TryGetValue(req.EndPoint, out peer))
                            {
                                log.Debug($"Broker is starting a connection to {req.EndPoint}");
                                mrucache.Add(req.EndPoint, req.Key);
                                peer = peers[req.EndPoint] =
                                    PeerConnection.CreatePeer(
                                        node,
                                        new PeerInfo(req.Key, req.EndPoint),
                                        () => ConnectToPeerAsync(req.EndPoint),
                                        REQ_BUFFER_SIZE
                                        );

                                if (req.Key != null)
                                {
                                    peersbykey[req.Key] = req.EndPoint;
                                }
                            }

                            await peer.Item2.WriteAsync(req);
                        }
                        catch (Exception ex)
                        {
                            log.Warn("Failed to send request to peer", ex);
                            try { await req.Response.WriteAsync(new ConnectionResponse()
                                {
                                    Exception = ex
                                }); }
                            catch (Exception ex2) { log.Warn("Failed to write failure response", ex2); }

                            if (peer != null)
                            {
                                try { peer.Item2.AsWriteOnly().Dispose(); }
                                catch (Exception ex2) { log.Warn("Failed to terminate write channel", ex2); }

                                try { await peer.Item1; }
                                catch (Exception ex2) { log.Warn("Peer connection stopped with error", ex2); }
                            }

                            peers.Remove(req.EndPoint);
                        }
                    }
                }
            }
                       ));
        }
Esempio n. 14
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        /// <summary>
        /// Runs a process that handles remote requests
        /// </summary>
        /// <param name="selfinfo">Description of the owning node</param>
        /// <param name="maxparallel">The maximum number of requests to handle in parallel</param>
        /// <returns>The async.</returns>
        public static Task RunAsync(PeerInfo selfinfo, int maxparallel = 10)
        {
            return(AutomationExtensions.RunTask(new
            {
                Requests = Channels.RemoteRequests.ForRead,
                Routing = Channels.RoutingTableRequests.ForWrite
            },
                                                async self =>
            {
                log.Debug("Running the remote handler");

                // Set up an error handler
                Func <ConnectionRequest, Exception, Task> errorHandler = async(t, ex) =>
                {
                    try
                    {
                        await t.Response.WriteAsync(new ConnectionResponse()
                        {
                            Exception = ex,
                            RequestID = t.RequestID
                        });
                    }
                    catch (Exception ex2)
                    {
                        log.Warn("Failed to send error response", ex2);
                    }
                };

                using (var tp = new TaskPool <ConnectionRequest>(maxparallel, errorHandler))
                    while (true)
                    {
                        log.Debug("Remote handler is waiting for requests ...");
                        var req = await self.Requests.ReadAsync();
                        log.Debug($"Remote handler got a {req.Request.Operation} request ({req.RequestID})");

                        await tp.Run(req, async() => {
                            log.Debug($"Remote handler is processing {req.Request.Operation} request ({req.RequestID})");
                            if (req.Key != null && req.EndPoint != null)
                            {
                                log.Debug($"Updating route table with remote request data {req.Key} - {req.EndPoint}");
                                await self.Routing.AddPeerAsync(req.Key, new PeerInfo(req.Key, req.EndPoint));
                            }

                            switch (req.Request.Operation)
                            {
                            case Protocol.Operation.Ping:
                                await HandlePingRequestAsync(selfinfo, req);
                                break;

                            case Protocol.Operation.Store:
                                await HandleStoreRequestAsync(selfinfo, req);
                                break;

                            case Protocol.Operation.FindValue:
                                await HandleFindRequestAsync(selfinfo, req);
                                break;

                            case Protocol.Operation.FindPeer:
                                await HandleNodeLookupRequestAsync(selfinfo, req);
                                break;

                            default:
                                await req.Response.WriteAsync(new ConnectionResponse()
                                {
                                    RequestID = req.RequestID,
                                    Exception = new Exception($"Invalid operation: {req.Request.Operation}")
                                });
                                break;
                            }

                            log.Debug($"Remote handler finished processing {req.Request.Operation} request ({req.RequestID})");
                        });
                    }
            }));
        }
Esempio n. 15
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 /// <summary>
 /// Gets the <paramref name="count"/> closest live nodes to the <paramref name="key"/>.
 /// </summary>
 /// <returns>The closest live peers.</returns>
 /// <param name="selfinfo">Selfinfo.</param>
 /// <param name="key">The key to search for.</param>
 public static Task <List <PeerInfo> > GetClosestPeers(PeerInfo selfinfo, Key key, int count)
 {
     return(Channels.RoutingTableRequests.Get().LookupPeerAsync(key));
 }
Esempio n. 16
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        /// <summary>
        /// Visits the <paramref name="k"/> closest peers and sends the <paramref name="request"/> message to them
        /// </summary>
        /// <returns>The number of nodes visited.</returns>
        /// <param name="selfinfo">Selfinfo.</param>
        /// <param name="key">The key to use for findng the closest nodes.</param>
        /// <param name="k">The redundancy parameter.</param>
        /// <param name="succes_count">The number of success responses to find</param>
        /// <param name="request">The request to send.</param>
        private static async Task <List <Protocol.Response> > VisitClosestPeers(PeerInfo selfinfo, Key key, int k, int succes_count, Protocol.Request request)
        {
            KeyDistance closesttried = null;

            var peers = await GetClosestPeers(selfinfo, key, k);

            log.Debug($"Initial query gave {peers.Count} peers");

            var used = new HashSet <Key>();

            var lck     = new object();
            var closest = new List <PeerInfo>();

            var cb = Channels.ConnectionBrokerRequests.Get();

            var success = new List <Protocol.Response>();

            using (var tp = new TaskPool <PeerInfo>(2, (p, ex) => log.Warn($"Request to peer {p.Key} - {p.Address} failed", ex)))
                while (success.Count < succes_count && (peers.Count + closest.Count > 0))
                {
                    peers = closest
                            .Union(peers)
                            // Remove dead items
                            .Where(x => !used.Contains(x.Key))
                            // Always move closer to the target for find
                            .Where(x => closesttried == null || (new KeyDistance(key, x.Key).CompareTo(closesttried)) <= 0)
                            // Sort by distance
                            .OrderBy(x => new KeyDistance(key, x.Key))
                            .ToList();

                    // Clean the list
                    closest.Clear();

                    log.Debug($"Sending request to {peers.Count} peers");

                    // Get the peers
                    var alloperations =
                        peers.Select(x => tp.Run(x, async() =>
                    {
                        log.Debug($"Success count {success.Count}, target: {succes_count}");
                        if (success.Count >= succes_count)
                        {
                            return;
                        }

                        log.Debug("Sending request via broker");
                        var r = cb.SendConnectionRequestAsync(x.Address, x.Key, request);

                        // Don't try this again
                        lock (lck)
                            used.Add(x.Key);

                        log.Debug($"Waiting for broker response {x.Key}...");
                        var res = await r;
                        log.Debug($"Peer response for {x.Key} obtained ({(res.Exception != null ? "exception": (res.Response.Success ? "success" : "no hit"))})");

                        // Skip error nodes
                        if (res.Exception != null)
                        {
                            log.Warn("Node request failed", res.Exception);
                            //await Channels.ConnectionBrokerRegistrations.Get().WriteAsync(new ConnectionRegistrationRequest() {
                            //    IsTerminate = true,
                            //    UpdateRouting = true,
                            //    Peer = x
                            //});

                            return;
                        }
                        // Record success
                        if (res.Response.Success)
                        {
                            lock (lck)
                                success.Add(res.Response);
                        }

                        // Stock up on peers, if any
                        if (res.Response.Peers != null)
                        {
                            lock (lck)
                                closest.AddRange(res.Response.Peers);
                        }

                        // If we are doing a find, narrow the scope
                        if (request.Operation == Protocol.Operation.FindValue)
                        {
                            if (closesttried == null || new KeyDistance(key, x.Key).CompareTo(closesttried) < 0)
                            {
                                closesttried = new KeyDistance(key, x.Key);
                            }
                        }
                    }));

                    await Task.WhenAll(alloperations);

                    await tp.FinishedAsync();

                    log.Debug($"Got {closest.Count} potential new peers");

                    if (closest.Count == 0)
                    {
                        break;
                    }
                }

            return(success);
        }
Esempio n. 17
0
        /// <summary>
        /// Runs the router and forwarder
        /// </summary>
        /// <returns>An awaitable result.</returns>
        /// <param name="owner">The owner of the routing table.</param>
        /// <param name="k">The redundancy parameter.</param>
        /// <param name="buffersize">The size of the forwarding buffer.</param>
        public static Task RunAsync(PeerInfo owner, int k, int buffersize = 10)
        {
            return(AutomationExtensions.RunTask(
                       new
            {
                Requests = Channels.RoutingTableRequests.ForRead,
                Stats = Channels.RoutingTableStats.ForRead,
                PeerReq = Channels.PeerRequests.ForWrite
            },

                       async self =>
            {
                // Setup the routing table, and add us to it
                var table = new RoutingTable(owner.Key, k);
                table.Add(owner);
                log.Debug($"Router is now running");

                // Set up the error handler
                Func <RoutingRequest, Exception, Task> errorHandler = async(t, ex) =>
                {
                    log.Warn("Routing operation failed, sending failure response to requester", ex);
                    try
                    {
                        await t.Response.WriteAsync(new RoutingResponse()
                        {
                            Exception = ex, Succes = false
                        });
                    }
                    catch (Exception ex2)
                    {
                        log.Warn("Failed to forward error message", ex2);
                    }
                };

                using (var tp = new TaskPool <RoutingRequest>(buffersize, errorHandler))
                    while (true)
                    {
                        // Wait for requests
                        log.Debug($"Router is waiting for requests ...");
                        var r = await MultiChannelAccess.ReadFromAnyAsync(self.Stats.RequestRead(), self.Requests.RequestRead());
                        if (r.Channel == self.Stats)
                        {
                            log.Debug($"Router got stat request");

                            var m = (IWriteChannel <RoutingStatsResponse>)r.Value;
                            await m.WriteAsync(new RoutingStatsResponse()
                            {
                                Count = table.Count,
                                Stats = (Channels.RoutingTableRequests.Get() as ProfilingChannel <RoutingRequest>)?.ReportStats()
                            });
                            continue;
                        }

                        var data = (RoutingRequest)r.Value;
                        try
                        {
                            log.Debug($"Router got request {data.Operation}");
                            // Multiplex the operation
                            switch (data.Operation)
                            {
                            case RoutingOperation.Add:
                                {
                                    var success = table.Add(data.Data, out var isNew);
                                    if (data.Response != null)
                                    {
                                        await tp.Run(data, () => data.Response.WriteAsync(new RoutingResponse()
                                        {
                                            Succes = true, IsNew = isNew
                                        }));
                                    }

                                    // If the peer is new, discover what peers it knows
                                    if (isNew)
                                    {
                                        log.Debug($"New peer, requesting refresh");
                                        await tp.Run(data, () => self.PeerReq.WriteAsync(new PeerRequest()
                                        {
                                            Operation = PeerOperation.Refresh,
                                            Key = data.Data.Key
                                        }));
                                        log.Debug($"Peer refresh requested");
                                    }

                                    break;
                                }

                            case RoutingOperation.Remove:
                                {
                                    var sucess = table.RemoveKey(data.Key);
                                    if (data.Response != null)
                                    {
                                        await tp.Run(data, () => data.Response.WriteAsync(new RoutingResponse()
                                        {
                                            Succes = sucess
                                        }));
                                    }
                                    break;
                                }

                            case RoutingOperation.Lookup:
                                {
                                    var peers = table.Nearest(data.Key, k, data.OnlyKBucket);
                                    await tp.Run(data, () => data.Response.WriteAsync(new RoutingResponse()
                                    {
                                        Succes = true, Peers = peers
                                    }));
                                    break;
                                }

                            default:
                                throw new Exception($"Operation not supported: {data.Operation}");
                            }
                        }
                        catch (Exception ex)
                        {
                            await errorHandler(data, ex);
                        }
                    }
            }));
        }
Esempio n. 18
0
 /// <summary>
 /// Adds a peer to the routing table
 /// </summary>
 /// <returns><c>true</c> if the peer is new, <c>false</c> otherwise.</returns>
 /// <param name="channel">The channel to send the request on.</param>
 /// <param name="key">The key for the peer.</param>
 /// <param name="peer">The peer.</param>
 public static async Task <bool> AddPeerAsync(this IWriteChannel <RoutingRequest> channel, Key key, PeerInfo peer)
 {
     return((await SendMessageAsync <RoutingRequest, RoutingResponse>(channel, new RoutingRequest()
     {
         Operation = RoutingOperation.Add,
         Key = key,
         Data = peer
     })).IsNew);
 }
Esempio n. 19
0
        /// <summary>
        /// Runs a single peer connection, using the IPC link
        /// </summary>
        /// <returns>An awaitable task.</returns>
        /// <param name="self">This peer's information</param>
        /// <param name="remote">The remote peer's information</param>
        /// <param name="connecthandler">The method used to obtain the connection.</param>
        /// <param name="input">The channel for reading requests.</param>
        /// <param name="maxparallel">The maximum number of parallel handlers</param>
        private static async Task RunSingleConnection(PeerInfo self, PeerInfo remote, Func <Task <Stream> > connecthandler, IReadChannel <ConnectionRequest> input, int maxparallel)
        {
            // Get the local handler for remote requests
            var remotehandler = Channels.RemoteRequests.Get();

            LeanIPC.IPCPeer connection = null;

            try
            {
                if (connecthandler == null)
                {
                    throw new ArgumentNullException(nameof(connecthandler));
                }
                if (input == null)
                {
                    throw new ArgumentNullException(nameof(input));
                }

                log.Debug($"Setting up connection to {remote?.Key}");

                // Connect to the remote peer
                connection = new LeanIPC.IPCPeer(await connecthandler());

                // Setup a handler for remote requests, that forwards responses from the remote handler
                connection.AddUserTypeHandler <Protocol.Request>(
                    async(id, req) =>
                {
                    await connection.SendResponseAsync(id, (await remotehandler.SendConnectionRequestAsync(null, null, id, req)).Response);
                    return(true);
                }
                    );

                var mainTask  = connection.RunMainLoopAsync(self != remote);
                Key targetKey = null;

                // Grab a connection to update the routing table automatically
                var routingrequests = Channels.RoutingTableRequests.Get();

                log.Debug($"Peer connection running {self.Key}, {self.Address}");

                using (var tp = new TaskPool <ConnectionRequest>(maxparallel, (t, ex) => log.Warn("Unexpected error handling request", ex)))
                    while (true)
                    {
                        log.Debug($"Peer connection is waiting for request ...");

                        // Get either a local or a remote request
                        var req = await input.ReadAsync();

                        log.Debug($"Peer connection got request, handling on taskpool ...");

                        await tp.Run(req, () =>
                        {
                            log.Debug($"Peer connection is forwarding a local {req.Request.Operation} request to the remote");
                            return(Task.Run(async() =>
                            {
                                ConnectionResponse res;

                                try
                                {
                                    var p = await connection.SendAndWaitAsync <Protocol.Request, Protocol.Response>(req.Request);
                                    if (targetKey == null)
                                    {
                                        // Record the target key
                                        targetKey = p.Self.Key;
                                        if (remote == null || remote.Key == null)
                                        {
                                            remote = new PeerInfo(p.Self.Key, remote.Address);
                                        }

                                        // Write a registration request to the broker
                                        await Channels.ConnectionBrokerRegistrations.Get().WriteAsync(
                                            new ConnectionRegistrationRequest()
                                        {
                                            IsTerminate = false,
                                            UpdateRouting = true,
                                            Peer = remote
                                        }
                                            );

                                        log.Debug($"Registering peer in routing table: {remote.Key} {remote.Address} ...");
                                        await routingrequests.AddPeerAsync(remote.Key, remote);
                                    }

                                    if (p.Peers != null)
                                    {
                                        log.Debug($"Registering {p.Peers.Count} peers with the routing table ...");
                                        foreach (var peer in p.Peers)
                                        {
                                            await routingrequests.AddPeerAsync(peer.Key, peer);
                                        }

                                        log.Debug($"Registered {p.Peers.Count} peers with the routing table");
                                    }

                                    res = new ConnectionResponse()
                                    {
                                        Key = p.Self.Key,
                                        Response = p
                                    };
                                }
                                catch (Exception ex)
                                {
                                    log.Warn($"Failed to get result, sending error response", ex);
                                    res = new ConnectionResponse()
                                    {
                                        Key = targetKey,
                                        Exception = ex
                                    };

                                    log.Warn($"Killing peer due to the previous exception");
                                    await input.RetireAsync();
                                }

                                if (req.Response != null)
                                {
                                    try { await req.Response.WriteAsync(res); }
                                    catch (Exception ex) { log.Warn("Failed to send response", ex); }
                                }
                            }));
                        });
                    }
            }
            finally
            {
                await remotehandler.RetireAsync();

                if (connection != null)
                {
                    try { await connection.ShutdownAsync(); }
                    catch (Exception ex) { log.Warn("Failed to shut down IPC Peer", ex); }
                }

                // Write a registration request to the broker
                await Channels.ConnectionBrokerRegistrations.Get().WriteAsync(
                    new ConnectionRegistrationRequest()
                {
                    IsTerminate   = false,
                    UpdateRouting = false,
                    Peer          = remote
                }
                    );
            }
        }
Esempio n. 20
0
 /// <summary>
 /// Adds a peer to the routing table
 /// </summary>
 /// <returns><c>true</c> if the item was added; <c>false</c> otherwise.</returns>
 /// <param name="peer">Peer.</param>
 public bool Add(PeerInfo peer)
 {
     return(Add(peer, out var isNew));
 }
Esempio n. 21
0
        /// <summary>
        /// Runs the peer process
        /// </summary>
        /// <returns>An awaitable task.</returns>
        /// <param name="selfinfo">The information describing the peer.</param>
        /// <param name="k">The redundancy parameter.</param>
        /// <param name="storesize">The maximum size of the local store</param>
        /// <param name="maxage">The maximum age of items in the cache</param>
        /// <param name="initialContactlist">Initial list of peers to contact.</param>
        /// <param name="requests">The request channel for local management</param>
        public static async Task RunPeer(PeerInfo selfinfo, int k, int storesize, TimeSpan maxage, EndPoint[] initialContactlist, IReadChannel <PeerRequest> requests)
        {
            try
            {
                if (selfinfo == null)
                {
                    throw new ArgumentNullException(nameof(selfinfo));
                }
                if (initialContactlist == null)
                {
                    throw new ArgumentNullException(nameof(initialContactlist));
                }

                var ip = selfinfo.Address as IPEndPoint;
                if (ip == null)
                {
                    throw new ArgumentException($"Unable to convert {nameof(selfinfo.Address)} to a {nameof(IPEndPoint)}", nameof(selfinfo));
                }

                log.Debug($"Starting a peer with key {selfinfo.Key} and address {selfinfo.Address}");

                using (var scope = new IsolatedChannelScope())
                {
                    var sock = new TcpListener(ip);
                    sock.Start();

                    // Set up the helper processes
                    var router  = RoutingProcess.RunAsync(selfinfo, k);
                    var broker  = ConnectionBroker.RunAsync(selfinfo);
                    var values  = MRUProcess.RunAsync(selfinfo, storesize, maxage);
                    var remoter = RemoteProcess.RunAsync(selfinfo);

                    log.Debug("Started router, broker, and value store");

                    // Handle new connections
                    var listener = ListenAsync(selfinfo, sock);

                    log.Debug("Started listener");

                    // Start discovery of peers
                    var discovery = DiscoveryProcess.RunAsync(selfinfo, initialContactlist);

                    log.Debug("Started discovery");

                    // The process handling requests to the local node
                    var proc = AutomationExtensions.RunTask(
                        new
                    {
                        Requests = requests,
                        Refresh  = Channels.PeerRequests.ForRead,

                        // Add these, so this process terminates the others as well
                        BrokerReg  = Channels.ConnectionBrokerRegistrations.ForWrite,
                        BrokerReq  = Channels.ConnectionBrokerRequests.ForWrite,
                        BrokerStat = Channels.ConnectionBrokerStats.ForWrite,
                        MRUReq     = Channels.MRURequests.ForWrite,
                        MRUStat    = Channels.MRUStats.ForWrite,
                        RouteReq   = Channels.RoutingTableRequests.ForWrite,
                        RouteStat  = Channels.RoutingTableStats.ForWrite,
                    },
                        async self =>
                    {
                        log.Debug("Running peer main loop");

                        try
                        {
                            while (true)
                            {
                                var req = (await MultiChannelAccess.ReadFromAnyAsync(self.Requests, self.Refresh)).Value;
                                log.Debug($"Peer {selfinfo.Key} got message: {req.Operation}");
                                switch (req.Operation)
                                {
                                case PeerOperation.Add:
                                    await HandleAddOperation(selfinfo, req, k);
                                    break;

                                case PeerOperation.Find:
                                    await HandleFindOperation(selfinfo, req, k);
                                    break;

                                case PeerOperation.Stats:
                                    await HandleStatsOperation(req);
                                    break;

                                case PeerOperation.Refresh:
                                    await HandleRefreshOperation(selfinfo, req, k);
                                    break;

                                default:
                                    await req.Response.WriteAsync(new PeerResponse()
                                    {
                                        SuccessCount = -1
                                    });
                                    break;
                                }
                                log.Debug($"Peer {selfinfo.Key} handled message: {req.Operation}");
                            }
                        }
                        catch (Exception ex)
                        {
                            if (!ex.IsRetiredException())
                            {
                                log.Warn($"Terminating peer {selfinfo.Key} due to error", ex);
                            }
                            throw;
                        }
                        finally
                        {
                            log.Debug($"Terminating peer {selfinfo.Key}");
                        }
                    }
                        );

                    log.Debug("Started main handler");

                    // Set up a process that periodically emits refresh operations
                    var refresher = AutomationExtensions.RunTask(
                        new { Control = Channels.PeerRequests.ForWrite },
                        async self =>
                    {
                        var respchan = Channel.Create <PeerResponse>();
                        while (true)
                        {
                            // Sleep, but exit if the parent does
                            if (await Task.WhenAny(Task.Delay(TimeSpan.FromMinutes(10)), proc) == proc)
                            {
                                return;
                            }

                            await self.Control.WriteAsync(new PeerRequest()
                            {
                                Operation = PeerOperation.Refresh,
                                Response  = respchan
                            });
                            await respchan.ReadAsync();
                        }
                    }
                        );

                    log.Debug("Started refresh process, peer is now live");
                    await proc;
                    await router;
                    await broker;
                    await values;
                    await remoter;
                    await discovery;
                    await refresher;

                    await Task.WhenAll(router, broker, values, remoter, discovery, refresher);
                }
            }
            catch (Exception ex)
            {
                log.Warn("Failed to start peer", ex);

                try { await requests.RetireAsync(); }
                catch (Exception ex2) { log.Warn("Failed to stop the input channel", ex2); }

                log.Debug($"Peer with key {selfinfo.Key} and address {selfinfo.Address} stopped...");

                throw;
            }
        }
Esempio n. 22
0
        /// <summary>
        /// Runs the console interface
        /// </summary>
        /// <returns>An awaitable task.</returns>
        public static Task RunAsync()
        {
            // Set up a console forwarder process
            var consoleOut = Skeletons.CollectAsync(
                Channels.ConsoleOutput.ForRead,
                x => Console.Out.WriteLineAsync(x ?? string.Empty)
                );

            // Set up a channel for sending control messages
            var inputChannel = Channel.Create <string>(buffersize: 10);

            // Set up the console reader process
            var consoleInput = AutomationExtensions.RunTask(
                new { Control = inputChannel.AsWrite() },
                async self =>
            {
                string line;

                // TODO: The blocking read prevents clean shutdown,
                // but direct access to the input stream has issues with the buffer
                while ((line = await Task.Run(() => Console.ReadLine())) != null)
                {
                    await self.Control.WriteAsync(line);
                }
            }
                );

            // Set up the control logic handler
            var proc = AutomationExtensions.RunTask(new
            {
                Control = inputChannel.AsRead(),
                Output  = Channels.ConsoleOutput.ForWrite
            },
                                                    async self =>
            {
                var peers = new List <Tuple <PeerInfo, Task, IWriteChannel <PeerRequest> > >();
                var rnd   = new Random();

                var portnr = 15000;

                await self.Output.WriteAsync(HELPTEXT);
                while (true)
                {
                    try
                    {
                        var commandline = await self.Control.ReadAsync() ?? string.Empty;
                        var command     = commandline.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).FirstOrDefault() ?? string.Empty;

                        if (string.Equals(command, "help", StringComparison.OrdinalIgnoreCase))
                        {
                            await self.Output.WriteAsync(HELPTEXT);
                        }
                        else if (string.Equals(command, "exit", StringComparison.OrdinalIgnoreCase) || string.Equals(command, "quit", StringComparison.OrdinalIgnoreCase))
                        {
                            return;
                        }
                        else if (string.Equals(command, "check", StringComparison.OrdinalIgnoreCase))
                        {
                            for (var i = peers.Count - 1; i >= 0; i--)
                            {
                                if (await peers[i].Item3.IsRetiredAsync)
                                {
                                    await self.Output.WriteAsync($"Peer {peers[i].Item1.Key} at {peers[i].Item1.Address} terminated");
                                    peers.RemoveAt(i);
                                }
                            }

                            await self.Output.WriteAsync($"Completed check, found {peers.Count} live peers");
                        }
                        else if (string.Equals(command, "node", StringComparison.OrdinalIgnoreCase))
                        {
                            var actions = commandline.Split(new char[] { ' ' }, 4, StringSplitOptions.RemoveEmptyEntries);

                            if (string.Equals(actions[1], "start", StringComparison.OrdinalIgnoreCase))
                            {
                                var pi = new PeerInfo(Key.CreateRandomKey(), new IPEndPoint(IPAddress.Loopback, portnr));

                                await self.Output.WriteAsync($"Starting node {pi.Key} on {pi.Address}");
                                var chan = Channel.Create <PeerRequest>();
                                var s    = Task.Run(() =>
                                                    Peer.RunPeer(
                                                        pi, 5, 100, TimeSpan.FromDays(1),
                                                        peers.Count == 0 ? new EndPoint[0] : new[] { peers[rnd.Next(0, peers.Count - 1)].Item1.Address },
                                                        chan.AsRead()
                                                        )
                                                    .ContinueWith(_ => inputChannel.WriteAsync("check"))
                                                    );

                                peers.Add(new Tuple <PeerInfo, Task, IWriteChannel <PeerRequest> >(pi, s, chan));
                                portnr++;
                            }
                            else if (string.Equals(actions[1], "list", StringComparison.OrdinalIgnoreCase))
                            {
                                if (actions.Length != 2)
                                {
                                    await self.Output.WriteAsync("The list command takes no arguments");
                                    continue;
                                }

                                for (var i = 0; i < peers.Count; i++)
                                {
                                    await self.Output.WriteAsync(string.Format("{0}: {1} - {2}", i, peers[i].Item1.Key, peers[i].Item1.Address));
                                }
                                await self.Output.WriteAsync(string.Empty);
                            }
                            else if (string.Equals(actions[1], "connect", StringComparison.OrdinalIgnoreCase))
                            {
                                actions = commandline.Split(new char[] { ' ' }, 5, StringSplitOptions.RemoveEmptyEntries);
                                if (actions.Length != 4)
                                {
                                    await self.Output.WriteAsync("The connect command needs exactly two arguments, the ip and the port");
                                    continue;
                                }

                                if (!IPAddress.TryParse(actions[2], out var ip))
                                {
                                    await self.Output.WriteAsync($"Failed to parse ip: {actions[2]}");
                                    continue;
                                }

                                if (!int.TryParse(actions[3], out var port))
                                {
                                    await self.Output.WriteAsync($"Failed to parse {actions[3]} as an integer");
                                    continue;
                                }

                                var pi = new PeerInfo(Key.CreateRandomKey(), new IPEndPoint(IPAddress.Loopback, portnr));
                                await self.Output.WriteAsync($"Starting node {pi.Key} on {pi.Address}");
                                var chan = Channel.Create <PeerRequest>();

                                var s = Task.Run(() =>
                                                 Peer.RunPeer(
                                                     pi, 5, 100, TimeSpan.FromDays(1),
                                                     new[] { new IPEndPoint(ip, port) },
                                                     chan.AsRead()
                                                     )
                                                 .ContinueWith(_ => inputChannel.WriteAsync("check"))
                                                 );

                                peers.Add(new Tuple <PeerInfo, Task, IWriteChannel <PeerRequest> >(pi, s, chan));
                                portnr++;
                            }
                            else if (string.Equals(actions[1], "stop", StringComparison.OrdinalIgnoreCase) || string.Equals(actions[1], "stat", StringComparison.OrdinalIgnoreCase) || string.Equals(actions[1], "refresh", StringComparison.OrdinalIgnoreCase))
                            {
                                if (actions.Length != 3)
                                {
                                    await self.Output.WriteAsync($"The {actions[1]} command takes exactly one argument, the node number");
                                    continue;
                                }

                                if (!int.TryParse(actions[2], out var ix))
                                {
                                    await self.Output.WriteAsync($"Failed to parse {actions[2]} as an integer");
                                    continue;
                                }

                                if (ix < 0 || ix >= peers.Count)
                                {
                                    await self.Output.WriteAsync($"The node number must be positive and less than {peers.Count}");
                                    continue;
                                }

                                if (string.Equals(actions[1], "stop", StringComparison.OrdinalIgnoreCase))
                                {
                                    await self.Output.WriteAsync($"Stopping node {ix} ({peers[ix].Item1.Key} at {peers[ix].Item1.Address}) ...");
                                    await peers[ix].Item3.RetireAsync();
                                    await self.Output.WriteAsync($"Stopped node ({peers[ix].Item1.Key} at {peers[ix].Item1.Address}) ...");
                                    //peers.RemoveAt(ix);
                                }
                                else if (string.Equals(actions[1], "stat", StringComparison.OrdinalIgnoreCase))
                                {
                                    await self.Output.WriteAsync($"Requesting stats from node {ix} ({peers[ix].Item1.Key} at {peers[ix].Item1.Address}) ...");
                                    var channel = Channel.Create <PeerResponse>();
                                    await peers[ix].Item3.WriteAsync(new PeerRequest()
                                    {
                                        Operation = PeerOperation.Stats,
                                        Response  = channel
                                    });

                                    await self.Output.WriteAsync($"Stats requested, waiting for response...");
                                    await self.Output.WriteAsync(System.Text.Encoding.UTF8.GetString((await channel.ReadAsync()).Data));
                                }
                                else if (string.Equals(actions[1], "refresh", StringComparison.OrdinalIgnoreCase))
                                {
                                    await self.Output.WriteAsync($"Performing refresh on {ix} ({peers[ix].Item1.Key} at {peers[ix].Item1.Address}) ...");

                                    var channel = Channel.Create <PeerResponse>();
                                    await peers[ix].Item3.WriteAsync(new PeerRequest()
                                    {
                                        Operation = PeerOperation.Refresh,
                                        Response  = channel
                                    });

                                    var res = await channel.ReadAsync();
                                    await self.Output.WriteAsync($"Refreshed with {res.SuccessCount} node(s)");
                                }
                                else
                                {
                                    await self.Output.WriteAsync($"Node action not recognized: {actions[1]}");
                                }
                            }
                            else
                            {
                                await self.Output.WriteAsync($"Node command not recognized: {actions[1]}");
                            }
                        }
                        else if (string.Equals(command, "add", StringComparison.OrdinalIgnoreCase))
                        {
                            var actions = commandline.Split(new char[] { ' ' }, 2, StringSplitOptions.RemoveEmptyEntries);
                            if (actions.Length == 1)
                            {
                                await self.Output.WriteAsync("The add command needs the value to add");
                                continue;
                            }
                            if (peers.Count == 0)
                            {
                                await self.Output.WriteAsync("The add command does not work if no nodes are started");
                                continue;
                            }

                            var channel = Channel.Create <PeerResponse>();
                            var data    = System.Text.Encoding.UTF8.GetBytes(actions[1]);
                            var key     = Key.ComputeKey(data);

                            await self.Output.WriteAsync($"Adding {data.Length} byte(s) with key {key}");
                            await peers[rnd.Next(0, peers.Count)].Item3.WriteAsync(new PeerRequest()
                            {
                                Operation = PeerOperation.Add,
                                Key       = key,
                                Data      = data,
                                Response  = channel,
                            });

                            await self.Output.WriteAsync("Send add request, waiting for completion");
                            var res = await channel.ReadAsync();
                            await self.Output.WriteAsync($"Add inserted into {res.SuccessCount} node(s)");
                        }
                        else if (string.Equals(command, "get", StringComparison.OrdinalIgnoreCase))
                        {
                            var actions = commandline.Split(new char[] { ' ' }, 3, StringSplitOptions.RemoveEmptyEntries);
                            if (actions.Length == 1)
                            {
                                await self.Output.WriteAsync("The get command needs the hash to find");
                                continue;
                            }
                            if (actions.Length == 3)
                            {
                                await self.Output.WriteAsync("The get command needs only one argument");
                                continue;
                            }
                            if (peers.Count == 0)
                            {
                                await self.Output.WriteAsync("The get command does not work if no nodes are started");
                                continue;
                            }

                            Key key;
                            try { key = new Key(actions[1]); }
                            catch (Exception ex)
                            {
                                await self.Output.WriteAsync($"Failed to parse key: {ex.Message}");
                                continue;
                            }


                            var channel = Channel.Create <PeerResponse>();

                            await self.Output.WriteAsync($"Locating key");
                            await peers[rnd.Next(0, peers.Count)].Item3.WriteAsync(new PeerRequest()
                            {
                                Operation = PeerOperation.Find,
                                Key       = key,
                                Response  = channel,
                            });

                            var res = await channel.ReadAsync();
                            if (res.Data == null)
                            {
                                await self.Output.WriteAsync($"Did not find the key ...");
                            }
                            else
                            {
                                await self.Output.WriteAsync($"Found: {System.Text.Encoding.UTF8.GetString(res.Data)}");
                            }
                        }
                        else if (string.Equals(command, "hash", StringComparison.OrdinalIgnoreCase))
                        {
                            var actions = commandline.Split(new char[] { ' ' }, 2, StringSplitOptions.RemoveEmptyEntries);
                            if (actions.Length == 1)
                            {
                                await self.Output.WriteAsync("The add command needs the value to add");
                                continue;
                            }

                            await self.Output.WriteAsync($"Key: {Key.ComputeKey(actions[1])}");
                        }
                        else
                        {
                            await self.Output.WriteAsync($"Command not recognized: {command}");
                        }
                    }
                    catch (Exception ex)
                    {
                        await self.Output.WriteAsync($"Command failed: {ex.Message}");
                    }
                }
            }
                                                    );

            return(Task.WhenAll(consoleOut /*, consoleInput*/, proc));
        }
Esempio n. 23
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        /// <summary>
        /// Runs the MRU cache
        /// </summary>
        /// <returns>An awaitable task.</returns>
        /// <param name="selfinfo">This peer's information</param>
        /// <param name="storesize">The size of the MRU store</param>
        /// <param name="maxage">The maximum amount of time items are stored</param>
        /// <param name="buffersize">The size of the parallel processing buffer</param>
        private static Task RunMRUAsync(PeerInfo selfinfo, int storesize, TimeSpan maxage, int buffersize)
        {
            var storechan = Channel.Create <MRUInternalStore>();

            return(AutomationExtensions.RunTask(new
            {
                Request = Channels.MRURequests.ForRead,
                Routing = Channels.RoutingTableRequests.ForWrite,
                Stats = Channels.MRUStats.ForRead,
                Store = storechan.AsRead()
            },
                                                async self =>
            {
                var cache = new MRUCache <Key, byte[]>(storesize, maxage);
                var store = new MRUCache <Key, byte[]>(int.MaxValue, maxage);

                log.Debug($"Store is now running");

                // Set up a shared error handler for logging and reporting errors
                Func <MRURequest, Exception, Task> errorHandler = async(req, ex) =>
                {
                    log.Warn("Failed to process request, sending error", ex);
                    try { await req.SendResponseAsync(ex); }
                    catch (Exception ex2) { log.Warn("Failed to forward error report", ex2); }
                };

                using (var tp = new TaskPool <MRURequest>(buffersize, errorHandler))
                    while (true)
                    {
                        log.Debug($"Store is waiting for requests ...");
                        var mreq = await MultiChannelAccess.ReadFromAnyAsync(
                            self.Stats.RequestRead(),
                            self.Store.RequestRead(),
                            self.Request.RequestRead()
                            );

                        if (mreq.Channel == self.Stats)
                        {
                            log.Debug($"Store got stat request");
                            var r = (IWriteChannel <MRUStatResponse>)mreq.Value;

                            await r.WriteAsync(new MRUStatResponse()
                            {
                                Items = cache.Count + store.Count,
                                Oldest = new DateTime(Math.Min(cache.OldestItem.Ticks, store.OldestItem.Ticks)),
                                Size = cache.Select(x => x.Value.Length).Sum() + store.Select(x => x.Value.Length).Sum(),
                                Stats = (Channels.MRURequests.Get() as ProfilingChannel <MRURequest>)?.ReportStats()
                            });
                            continue;
                        }

                        if (mreq.Channel == self.Store)
                        {
                            var sreq = (MRUInternalStore)mreq.Value;

                            log.Debug($"Store got internal store request");
                            var shouldBroadCast = sreq.Peers != null && !store.TryGetValue(sreq.Key, out _);
                            store.Add(sreq.Key, sreq.Data);

                            // We currently rely on the injector to broadcast,
                            // If we enable this, we need some logic to figure out
                            // the source of the Add, to both allow re-insertion
                            // and avoid repeated broadcasts if two peers determine
                            // they are *the* handling peer

                            //if (shouldBroadCast)
                            //await tp.Run(new MRURequest() { }, () => BroadcastValueAsync(selfinfo, sreq));

                            continue;
                        }

                        var req = (MRURequest)mreq.Value;
                        log.Debug($"Store got request {req.Operation}");
                        try
                        {
                            switch (req.Operation)
                            {
                            case MRUOperation.Add:
                                {
                                    // Always store it in our cache
                                    cache.Add(req.Key, req.Data);

                                    // Process long-term if needed
                                    await tp.Run(req, () => StoreLongTermAsync(selfinfo, self.Routing, storechan.AsWrite(), req.Key, req.Data));

                                    // Respond that we completed
                                    await tp.Run(req, () => req.SendResponseAsync(req.Key, null));
                                    break;
                                }

                            case MRUOperation.Get:
                                {
                                    var res = cache.TryGetValue(req.Key, out var data);
                                    if (!res)
                                    {
                                        res = store.TryGetValue(req.Key, out data);
                                    }

                                    await tp.Run(req, () => req.SendResponseAsync(req.Key, data, res));
                                    break;
                                }

                            case MRUOperation.Expire:
                                cache.ExpireOldItems();
                                store.ExpireOldItems();
                                await tp.Run(req, () => req.SendResponseAsync(null, null));
                                break;

                            default:
                                throw new Exception($"Unable to handle request with type {req.Operation}");
                            }
                            log.Debug($"Store completed request {req.Operation}");
                        }
                        catch (Exception ex)
                        {
                            await errorHandler(req, ex);
                        }
                    }
            }));
        }