public Task OnDisconnectedAsync(IConnectionContext connection)
{
_connections.Remove(connection);
var tasks = new List <Task>();
var connectionChannel = _channels.Connection(connection.ConnectionId);
RedisLog.Unsubscribe(_logger, connectionChannel);
tasks.Add(_bus.UnsubscribeAsync(connectionChannel));
var feature = connection.Features.Get <IRedisFeature>();
var groupNames = feature.Groups;
if (groupNames != null)
{
// Copy the groups to an array here because they get removed from this collection
// in RemoveFromGroupAsync
foreach (var group in groupNames.ToArray())
{
// Use RemoveGroupAsyncCore because the connection is local and we don't want to
// accidentally go to other servers with our remove request.
tasks.Add(RemoveGroupAsyncCore(connection, group));
}
}
if (!string.IsNullOrEmpty(connection.UserIdentifier))
{
tasks.Add(RemoveUserAsync(connection));
}
return(Task.WhenAll(tasks));
}
private Task SubscribeToUser(IConnectionContext connection)
{
var userChannel = _channels.User(connection.UserIdentifier);
return(_users.AddSubscriptionAsync(userChannel, connection, async(channelName, subscriptions) =>
{
RedisLog.Subscribing(_logger, channelName);
var channel = await _bus.SubscribeAsync(channelName);
channel.OnMessage(async channelMessage =>
{
try
{
var invocation = _protocol.ReadInvocation((byte[])channelMessage.Message);
var tasks = new List <Task>();
foreach (var userConnection in subscriptions)
{
tasks.Add(userConnection.WriteAsync(invocation.Message, CancellationToken.None));
}
await Task.WhenAll(tasks);
}
catch (Exception ex)
{
RedisLog.FailedWritingMessage(_logger, ex);
}
});
}));
}
private async Task SubscribeToGroupAsync(string groupChannel, ConnectionStore groupConnections)
{
RedisLog.Subscribing(_logger, groupChannel);
var channel = await _bus.SubscribeAsync(groupChannel);
channel.OnMessage(async(channelMessage) =>
{
try
{
var invocation = _protocol.ReadInvocation((byte[])channelMessage.Message);
var tasks = new List <Task>();
foreach (var groupConnection in groupConnections)
{
if (invocation.ExcludedConnectionIds?.Contains(groupConnection.ConnectionId) == true)
{
continue;
}
tasks.Add(groupConnection.WriteAsync(invocation.Message, CancellationToken.None));
}
await Task.WhenAll(tasks);
}
catch (Exception ex)
{
RedisLog.FailedWritingMessage(_logger, ex);
}
});
}
private async Task SubscribeToAll()
{
RedisLog.Subscribing(_logger, _channels.All);
var channel = await _bus.SubscribeAsync(_channels.All);
channel.OnMessage(async channelMessage =>
{
try
{
RedisLog.ReceivedFromChannel(_logger, _channels.All);
var invocation = _protocol.ReadInvocation((byte[])channelMessage.Message);
var tasks = new List <Task>(_connections.Count);
foreach (var connection in _connections)
{
if (invocation.ExcludedConnectionIds == null || !invocation.ExcludedConnectionIds.Contains(connection.ConnectionId))
{
tasks.Add(connection.WriteAsync(invocation.Message, CancellationToken.None));
}
}
await Task.WhenAll(tasks);
}
catch (Exception ex)
{
RedisLog.FailedWritingMessage(_logger, ex);
}
});
}
private async Task PublishAsync(string channel, byte[] payload)
{
await EnsureRedisServerConnection();
RedisLog.PublishToChannel(_logger, channel);
await _bus.PublishAsync(channel, payload);
}
private async Task EnsureRedisServerConnection()
{
if (_redisServerConnection == null)
{
await _connectionLock.WaitAsync();
try
{
if (_redisServerConnection == null)
{
var writer = new LoggerTextWriter(_logger);
_redisServerConnection = await _options.ConnectAsync(writer);
_bus = _redisServerConnection.GetSubscriber();
_redisServerConnection.ConnectionRestored += (_, e) =>
{
// We use the subscription connection type
// Ignore messages from the interactive connection (avoids duplicates)
if (e.ConnectionType == ConnectionType.Interactive)
{
return;
}
RedisLog.ConnectionRestored(_logger);
};
_redisServerConnection.ConnectionFailed += (_, e) =>
{
// We use the subscription connection type
// Ignore messages from the interactive connection (avoids duplicates)
if (e.ConnectionType == ConnectionType.Interactive)
{
return;
}
RedisLog.ConnectionFailed(_logger, e.Exception);
};
if (_redisServerConnection.IsConnected)
{
RedisLog.Connected(_logger);
}
else
{
RedisLog.NotConnected(_logger);
}
await SubscribeToAll();
await SubscribeToGroupManagementChannel();
await SubscribeToAckChannel();
}
}
finally
{
_connectionLock.Release();
}
}
}
private Task RemoveUserAsync(IConnectionContext connection)
{
var userChannel = _channels.User(connection.UserIdentifier);
return(_users.RemoveSubscriptionAsync(userChannel, connection, channelName =>
{
RedisLog.Unsubscribe(_logger, channelName);
return _bus.UnsubscribeAsync(channelName);
}));
}
public RedisConnectionLifetimeManager(ILogger <RedisConnectionLifetimeManager> logger,
IOptions <RedisOptions> options)
{
_logger = logger;
_options = options.Value;
_ackHandler = new AckHandler();
_channels = new RedisChannels("RedisConnectionLifetimeManager");
_protocol = new RedisProtocol();
RedisLog.ConnectingToEndpoints(_logger, options.Value.Configuration.EndPoints, _serverName);
_ = EnsureRedisServerConnection();
}
private async Task SubscribeToConnection(IConnectionContext connection)
{
var connectionChannel = _channels.Connection(connection.ConnectionId);
RedisLog.Subscribing(_logger, connectionChannel);
var channel = await _bus.SubscribeAsync(connectionChannel);
channel.OnMessage(channelMessage =>
{
var invocation = _protocol.ReadInvocation((byte[])channelMessage.Message);
return(connection.WriteAsync(invocation.Message, CancellationToken.None));
});
}
/// <summary>
/// This takes <see cref="HubConnectionContext"/> because we want to remove the connection from the
/// _connections list in OnDisconnectedAsync and still be able to remove groups with this method.
/// </summary>
private async Task RemoveGroupAsyncCore(IConnectionContext connection, string groupName)
{
var groupChannel = _channels.Group(groupName);
await _groups.RemoveSubscriptionAsync(groupChannel, connection, channelName =>
{
RedisLog.Unsubscribe(_logger, channelName);
return(_bus.UnsubscribeAsync(channelName));
});
var feature = connection.Features.Get <IRedisFeature>();
var groupNames = feature.Groups;
if (groupNames != null)
{
lock (groupNames)
{
groupNames.Remove(groupName);
}
}
}
private async Task SubscribeToGroupManagementChannel()
{
var channel = await _bus.SubscribeAsync(_channels.GroupManagement);
channel.OnMessage(async channelMessage =>
{
try
{
var groupMessage = _protocol.ReadGroupCommand((byte[])channelMessage.Message);
var connection = _connections[groupMessage.ConnectionId];
if (connection == null)
{
// user not on this server
return;
}
if (groupMessage.Action == GroupAction.Remove)
{
await RemoveGroupAsyncCore(connection, groupMessage.GroupName);
}
if (groupMessage.Action == GroupAction.Add)
{
await AddGroupAsyncCore(connection, groupMessage.GroupName);
}
// Send an ack to the server that sent the original command.
await PublishAsync(_channels.Ack(groupMessage.ServerName), _protocol.WriteAck(groupMessage.Id));
}
catch (Exception ex)
{
RedisLog.InternalMessageFailed(_logger, ex);
}
});
}
public override void WriteLine(string value)
{
RedisLog.ConnectionMultiplexerMessage(_logger, value);
}
