internal async Task <IRoutingTable> UpdateRoutingTableAsync(AccessMode mode,
string database, Bookmark bookmark)
{
if (database == null)
{
throw new ArgumentNullException(nameof(database));
}
_logger?.Debug("Updating routing table for database '{0}'.", database);
var existingTable = RoutingTableFor(database);
if (existingTable == null)
{
existingTable = new RoutingTable(database, Enumerable.Empty <Uri>());
}
var hasPrependedInitialRouters = false;
if (existingTable.IsReadingInAbsenceOfWriter(mode))
{
var uris = _initialServerAddressProvider.Get();
await PrependRoutersAsync(existingTable, uris).ConfigureAwait(false);
hasPrependedInitialRouters = true;
}
var triedUris = new HashSet <Uri>();
var newRoutingTable = await UpdateRoutingTableAsync(existingTable, mode, database, bookmark, triedUris)
.ConfigureAwait(false);
if (newRoutingTable != null)
{
return(newRoutingTable);
}
if (!hasPrependedInitialRouters)
{
var uris = _initialServerAddressProvider.Get();
uris.ExceptWith(triedUris);
if (uris.Count != 0)
{
await PrependRoutersAsync(existingTable, uris).ConfigureAwait(false);
newRoutingTable = await UpdateRoutingTableAsync(existingTable, mode, database, bookmark)
.ConfigureAwait(false);
if (newRoutingTable != null)
{
return(newRoutingTable);
}
}
}
// We tried our best however there is just no cluster.
// This is the ultimate place we will inform the user that a new driver to be created.
throw new ServiceUnavailableException(
"Failed to connect to any routing server. " +
"Please make sure that the cluster is up and can be accessed by the driver and retry.");
}
public async Task <bool> SupportsMultiDbAsync()
{
var uris = _initialServerAddressProvider.Get();
await AddConnectionPoolAsync(uris).ConfigureAwait(false);
var exceptions = new List <Exception>();
foreach (var uri in uris)
{
try
{
var connection = await CreateClusterConnectionAsync(uri, Simple.Mode, Simple.Database,
Simple.Bookmark).ConfigureAwait(false);
var multiDb = connection.SupportsMultidatabase();
await connection.CloseAsync().ConfigureAwait(false);
return(multiDb);
}
catch (SecurityException)
{
throw; // immediately stop
}
catch (Exception e)
{
exceptions.Add(e); // save and continue with the next server
}
}
throw new ServiceUnavailableException(
$"Failed to perform multi-databases feature detection with the following servers: {uris.ToContentString()} ",
new AggregateException(exceptions));
}
internal async Task <IRoutingTable> UpdateRoutingTableWithInitialUriFallbackAsync(
Func <ISet <Uri>, Task <IRoutingTable> > updateRoutingTableFunc = null)
{
_logger?.Debug("Updating routing table.");
var hasPrependedInitialRouters = false;
if (IsReadingInAbsenceOfWriter)
{
var uris = _initialServerAddressProvider.Get();
await PrependRoutersAsync(uris).ConfigureAwait(false);
hasPrependedInitialRouters = true;
}
var triedUris = new HashSet <Uri>();
var routingTable = await UpdateRoutingTableAsync(triedUris).ConfigureAwait(false);
if (routingTable != null)
{
return(routingTable);
}
if (!hasPrependedInitialRouters)
{
var uris = _initialServerAddressProvider.Get();
uris.ExceptWith(triedUris);
if (uris.Count != 0)
{
await PrependRoutersAsync(uris).ConfigureAwait(false);
routingTable = await UpdateRoutingTableAsync(null).ConfigureAwait(false);
if (routingTable != null)
{
return(routingTable);
}
}
}
// We retied and tried our best however there is just no cluster.
// This is the ultimate place we will inform the user that you need to re-create a driver
throw new ServiceUnavailableException(
"Failed to connect to any routing server. " +
"Please make sure that the cluster is up and can be accessed by the driver and retry.");
}
internal IRoutingTable UpdateRoutingTableWithInitialUriFallback(
Func <ISet <Uri>, IRoutingTable> updateRoutingTableFunc = null)
{
updateRoutingTableFunc = updateRoutingTableFunc ?? (u => UpdateRoutingTable(u));
var hasPrependedInitialRouters = false;
if (IsReadingInAbsenceOfWriter)
{
// to prevent from only talking to minority part of a partitioned cluster.
PrependRouters(_initialServerAddressProvider.Get());
hasPrependedInitialRouters = true;
}
var triedUris = new HashSet <Uri>();
var routingTable = updateRoutingTableFunc(triedUris);
if (routingTable != null)
{
return(routingTable);
}
if (!hasPrependedInitialRouters)
{
var uris = _initialServerAddressProvider.Get();
uris.ExceptWith(triedUris);
if (uris.Count != 0)
{
PrependRouters(uris);
routingTable = updateRoutingTableFunc(null);
if (routingTable != null)
{
return(routingTable);
}
}
}
// We retied and tried our best however there is just no cluster.
// This is the ultimate place we will inform the user that you need to re-create a driver
throw new ServiceUnavailableException(
"Failed to connect to any routing server. " +
"Please make sure that the cluster is up and can be accessed by the driver and retry.");
}