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 RemoveUserAsync(IConnectionContext connection)
{
var userChannel = _channels.User(connection.UserIdentifier);
return(_users.RemoveSubscriptionAsync(userChannel, connection, channelName =>
{
RedisLog.Unsubscribe(_logger, channelName);
return _bus.UnsubscribeAsync(channelName);
}));
}
/// <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);
}
}
}
