// constructors
internal MongoConnectionPool(MongoServerInstance serverInstance)
{
_settings = serverInstance.Settings;
_serverInstance = serverInstance;
_poolSize = 0;
_defaultAcquireConnectionOptions = new AcquireConnectionOptions
{
OkToAvoidWaitingByCreatingNewConnection = true,
OkToExceedMaxConnectionPoolSize = false,
OkToExceedWaitQueueSize = false,
WaitQueueTimeout = _settings.WaitQueueTimeout
};
}
// constructors
internal MongoConnectionPool(MongoServerInstance serverInstance)
{
_settings = serverInstance.Settings;
_serverInstance = serverInstance;
_poolSize = 0;
_defaultAcquireConnectionOptions = new AcquireConnectionOptions
{
OkToAvoidWaitingByCreatingNewConnection = true,
OkToExceedMaxConnectionPoolSize = false,
OkToExceedWaitQueueSize = false,
WaitQueueTimeout = _settings.WaitQueueTimeout
};
}
internal MongoConnection AcquireConnection(AcquireConnectionOptions options)
{
MongoConnection connectionToClose = null;
try
{
DateTime timeoutAt = DateTime.UtcNow + options.WaitQueueTimeout;
lock (_connectionPoolLock)
{
if (_waitQueueSize >= _settings.WaitQueueSize && !options.OkToExceedWaitQueueSize)
{
throw new MongoConnectionException("Too many threads are already waiting for a connection.");
}
_waitQueueSize += 1;
try
{
while (true)
{
if (_availableConnections.Count > 0)
{
var connection = _availableConnections[_availableConnections.Count - 1];
if (connection.IsExpired())
{
connectionToClose = connection;
connection = new MongoConnection(this);
}
_availableConnections.RemoveAt(_availableConnections.Count - 1);
return connection;
}
// avoid waiting by creating a new connection if options allow it
if (options.OkToAvoidWaitingByCreatingNewConnection)
{
if (_poolSize < _settings.MaxConnectionPoolSize || options.OkToExceedMaxConnectionPoolSize)
{
// make sure connection is created successfully before incrementing poolSize
// connection will be opened later outside of the lock
var connection = new MongoConnection(this);
_poolSize += 1;
return connection;
}
}
// wait for a connection to be released
var timeRemaining = timeoutAt - DateTime.UtcNow;
if (timeRemaining > TimeSpan.Zero)
{
// other methods should call Monitor.Pulse whenever:
// 1. an available connection is added _availableConnections
// 2. the _poolSize changes
Monitor.Wait(_connectionPoolLock, timeRemaining);
}
else
{
if (options.OkToExceedMaxConnectionPoolSize)
{
// make sure connection is created successfully before incrementing poolSize
// connection will be opened later outside of the lock
var connection = new MongoConnection(this);
_poolSize += 1;
return connection;
}
else
{
throw new TimeoutException("Timeout waiting for a MongoConnection.");
}
}
}
}
finally
{
_waitQueueSize -= 1;
}
}
}
finally
{
if (connectionToClose != null)
{
try
{
connectionToClose.Close();
}
catch
{
// ignore exceptions
}
}
}
}
internal MongoConnection AcquireConnection(AcquireConnectionOptions options)
{
MongoConnection connectionToClose = null;
try
{
DateTime timeoutAt = DateTime.UtcNow + options.WaitQueueTimeout;
lock (_connectionPoolLock)
{
if (_waitQueueSize >= _settings.WaitQueueSize && !options.OkToExceedWaitQueueSize)
{
throw new MongoConnectionException("Too many threads are already waiting for a connection.");
}
_waitQueueSize += 1;
try
{
while (true)
{
if (_availableConnections.Count > 0)
{
var connection = _availableConnections[_availableConnections.Count - 1];
if (connection.IsExpired())
{
connectionToClose = connection;
connection = new MongoConnection(this);
}
_availableConnections.RemoveAt(_availableConnections.Count - 1);
return(connection);
}
// avoid waiting by creating a new connection if options allow it
if (options.OkToAvoidWaitingByCreatingNewConnection)
{
if (_poolSize < _settings.MaxConnectionPoolSize || options.OkToExceedMaxConnectionPoolSize)
{
// make sure connection is created successfully before incrementing poolSize
// connection will be opened later outside of the lock
var connection = new MongoConnection(this);
_poolSize += 1;
return(connection);
}
}
// wait for a connection to be released
var timeRemaining = timeoutAt - DateTime.UtcNow;
if (timeRemaining > TimeSpan.Zero)
{
// other methods should call Monitor.Pulse whenever:
// 1. an available connection is added _availableConnections
// 2. the _poolSize changes
Monitor.Wait(_connectionPoolLock, timeRemaining);
}
else
{
if (options.OkToExceedMaxConnectionPoolSize)
{
// make sure connection is created successfully before incrementing poolSize
// connection will be opened later outside of the lock
var connection = new MongoConnection(this);
_poolSize += 1;
return(connection);
}
else
{
throw new TimeoutException("Timeout waiting for a MongoConnection.");
}
}
}
}
finally
{
_waitQueueSize -= 1;
}
}
}
finally
{
if (connectionToClose != null)
{
try
{
connectionToClose.Close();
}
catch
{
// ignore exceptions
}
}
}
}
internal MongoConnection AcquireConnection(string databaseName, MongoCredentials credentials, AcquireConnectionOptions options)
{
MongoConnection connectionToClose = null;
try
{
DateTime timeoutAt = DateTime.UtcNow + options.WaitQueueTimeout;
lock (_connectionPoolLock)
{
if (_waitQueueSize >= _settings.WaitQueueSize && !options.OkToExceedWaitQueueSize)
{
throw new MongoConnectionException("Too many threads are already waiting for a connection.");
}
_waitQueueSize += 1;
try
{
while (true)
{
if (_availableConnections.Count > 0)
{
// first try to find the most recently used connection that is already authenticated for this database
for (int i = _availableConnections.Count - 1; i >= 0; i--)
{
var connection = _availableConnections[i];
if (connection.IsExpired())
{
_availableConnections.RemoveAt(i);
connectionToClose = connection;
return new MongoConnection(this);
}
else if (connection.IsAuthenticated(databaseName, credentials))
{
_availableConnections.RemoveAt(i);
return connection;
}
}
// otherwise find the most recently used connection that can be authenticated for this database
for (int i = _availableConnections.Count - 1; i >= 0; i--)
{
var connection = _availableConnections[i];
if (connection.CanAuthenticate(databaseName, credentials))
{
_availableConnections.RemoveAt(i);
return connection;
}
}
// otherwise replace the least recently used connection with a brand new one
// if this happens a lot the connection pool size should be increased
connectionToClose = _availableConnections[0];
_availableConnections.RemoveAt(0);
return new MongoConnection(this);
}
// avoid waiting by creating a new connection if options allow it
if (options.OkToAvoidWaitingByCreatingNewConnection)
{
if (_poolSize < _settings.MaxConnectionPoolSize || options.OkToExceedMaxConnectionPoolSize)
{
// make sure connection is created successfully before incrementing poolSize
// connection will be opened later outside of the lock
var connection = new MongoConnection(this);
_poolSize += 1;
return connection;
}
}
// wait for a connection to be released
var timeRemaining = timeoutAt - DateTime.UtcNow;
if (timeRemaining > TimeSpan.Zero)
{
// other methods should call Monitor.Pulse whenever:
// 1. an available connection is added _availableConnections
// 2. the _poolSize changes
Monitor.Wait(_connectionPoolLock, timeRemaining);
}
else
{
if (options.OkToExceedMaxConnectionPoolSize)
{
// make sure connection is created successfully before incrementing poolSize
// connection will be opened later outside of the lock
var connection = new MongoConnection(this);
_poolSize += 1;
return connection;
}
else
{
throw new TimeoutException("Timeout waiting for a MongoConnection.");
}
}
}
}
finally
{
_waitQueueSize -= 1;
}
}
}
finally
{
if (connectionToClose != null)
{
try
{
connectionToClose.Close();
}
catch
{
// ignore exceptions
}
}
}
}
