/// <summary>
/// Utility that simplifies awaiting a task with a timeout. If the given task does not
/// complete within <paramref name="timeout"/>, a <see cref="TimeoutException"/> is thrown.
/// </summary>
/// <param name="task">The task to be awaited</param>
/// <param name="timeout">How much time to allow <paramref name="task"/> to complete before throwing a <see cref="TimeoutException"/></param>
/// <returns>An awaitable task that represents the original task plus the timeout</returns>
internal static async Task WithTimeout(this Task task, NpgsqlTimeout timeout)
{
if (!timeout.IsSet)
{
await task;
return;
}
var timeLeft = timeout.TimeLeft;
if (timeLeft < TimeSpan.Zero)
{
throw new TimeoutException();
}
var timeoutTask = Task.Delay(timeLeft);
if (task != await Task.WhenAny(task, timeoutTask))
{
throw new TimeoutException();
}
await task;
}
async Task Authenticate(string username, NpgsqlTimeout timeout, bool async, CancellationToken cancellationToken)
{
Log.Trace("Authenticating...", Id);
timeout.CheckAndApply(this);
var msg = Expect <AuthenticationRequestMessage>(await ReadMessage(async), this);
switch (msg.AuthRequestType)
{
case AuthenticationRequestType.AuthenticationOk:
return;
case AuthenticationRequestType.AuthenticationCleartextPassword:
await AuthenticateCleartext(username, async, cancellationToken);
return;
case AuthenticationRequestType.AuthenticationMD5Password:
await AuthenticateMD5(username, ((AuthenticationMD5PasswordMessage)msg).Salt, async, cancellationToken);
return;
case AuthenticationRequestType.AuthenticationSASL:
await AuthenticateSASL(((AuthenticationSASLMessage)msg).Mechanisms, username, async, cancellationToken);
return;
case AuthenticationRequestType.AuthenticationGSS:
case AuthenticationRequestType.AuthenticationSSPI:
await AuthenticateGSS(async);
return;
case AuthenticationRequestType.AuthenticationGSSContinue:
throw new NpgsqlException("Can't start auth cycle with AuthenticationGSSContinue");
default:
throw new NotSupportedException($"Authentication method not supported (Received: {msg.AuthRequestType})");
}
}
internal ValueTask <NpgsqlConnector> Allocate(NpgsqlConnection conn, NpgsqlTimeout timeout, bool async, CancellationToken cancellationToken)
{
Monitor.Enter(this);
while (Idle.Count > 0)
{
var connector = Idle.Pop();
// An idle connector could be broken because of a keepalive
if (connector.IsBroken)
{
continue;
}
connector.Connection = conn;
IncrementBusy();
EnsurePruningTimerState();
Monitor.Exit(this);
return(new ValueTask <NpgsqlConnector>(connector));
}
// No idle connectors available. Have to actually open a new connector or wait for one.
return(AllocateLong(conn, timeout, async, cancellationToken));
}
/// <summary>
/// Called exactly once per multiplexing pool, when the first connection is opened, with two goals:
/// 1. Load types and bind the pool-wide type mapper (necessary for binding parameters)
/// 2. Cause any connection exceptions (e.g. bad username) to be thrown from NpgsqlConnection.Open
/// </summary>
internal async Task BootstrapMultiplexing(NpgsqlConnection conn, NpgsqlTimeout timeout, bool async, CancellationToken cancellationToken = default)
{
Debug.Assert(_multiplexing);
var hasSemaphore = async
? await _bootstrapSemaphore !.WaitAsync(timeout.TimeLeft, cancellationToken)
: _bootstrapSemaphore !.Wait(timeout.TimeLeft, cancellationToken);
// We've timed out - calling Check, to throw the correct exception
if (!hasSemaphore)
{
timeout.Check();
}
try
{
if (IsBootstrapped)
{
return;
}
var connector = await conn.StartBindingScope(ConnectorBindingScope.Connection, timeout, async, cancellationToken);
using var _ = Defer(() => conn.EndBindingScope(ConnectorBindingScope.Connection));
// Somewhat hacky. Extract the connector's type mapper as our pool-wide mapper,
// and have the connector rebind to ensure it has a different instance.
// The latter isn't strictly necessary (type mappers should always be usable
// concurrently) but just in case.
MultiplexingTypeMapper = connector.TypeMapper;
connector.RebindTypeMapper();
IsBootstrapped = true;
}
finally
{
_bootstrapSemaphore !.Release();
}
}
/// <summary>
/// Called exactly once per multiplexing pool, when the first connection is opened, with two goals:
/// 1. Load types and bind the pool-wide type mapper (necessary for binding parameters)
/// 2. Cause any connection exceptions (e.g. bad username) to be thrown from NpgsqlConnection.Open
/// </summary>
internal async Task BootstrapMultiplexing(NpgsqlConnection conn, NpgsqlTimeout timeout, bool async, CancellationToken cancellationToken = default)
{
Debug.Assert(_multiplexing);
var hasSemaphore = async
? await _bootstrapSemaphore !.WaitAsync(timeout.TimeLeft, cancellationToken)
: _bootstrapSemaphore !.Wait(timeout.TimeLeft, cancellationToken);
// We've timed out - calling Check, to throw the correct exception
if (!hasSemaphore)
{
timeout.Check();
}
try
{
if (IsBootstrapped)
{
return;
}
var connector = await conn.StartBindingScope(ConnectorBindingScope.Connection, timeout, async, cancellationToken);
using var _ = Defer(static conn => conn.EndBindingScope(ConnectorBindingScope.Connection), conn);
internal async ValueTask <NpgsqlConnector> AllocateLong(NpgsqlConnection conn, NpgsqlTimeout timeout, bool async, CancellationToken cancellationToken)
{
Debug.Assert(Monitor.IsEntered(this));
NpgsqlConnector connector;
Debug.Assert(Busy <= _max);
if (Busy == _max)
{
// TODO: Async cancellation
var tcs = new TaskCompletionSource <NpgsqlConnector>();
_waiting.Enqueue(new WaitingOpenAttempt {
TaskCompletionSource = tcs, IsAsync = async
});
Monitor.Exit(this);
try
{
if (async)
{
if (timeout.IsSet)
{
var timeLeft = timeout.TimeLeft;
if (timeLeft <= TimeSpan.Zero || tcs.Task != await Task.WhenAny(tcs.Task, Task.Delay(timeLeft)))
{
throw new NpgsqlException($"The connection pool has been exhausted, either raise MaxPoolSize (currently {_max}) or Timeout (currently {Settings.Timeout} seconds)");
}
}
else
{
await tcs.Task;
}
}
else
{
if (timeout.IsSet)
{
var timeLeft = timeout.TimeLeft;
if (timeLeft <= TimeSpan.Zero || !tcs.Task.Wait(timeLeft))
{
throw new NpgsqlException($"The connection pool has been exhausted, either raise MaxPoolSize (currently {_max}) or Timeout (currently {Settings.Timeout} seconds)");
}
}
else
{
tcs.Task.Wait();
}
}
}
catch
{
// We're here if the timeout expired or the cancellation token was triggered
// Re-lock and check in case the task was set to completed after coming out of the Wait
lock (this)
{
if (!tcs.Task.IsCompleted)
{
tcs.SetCanceled();
throw;
}
}
}
connector = tcs.Task.Result;
connector.Connection = conn;
return(connector);
}
// No idle connectors are available, and we're under the pool's maximum capacity.
IncrementBusy();
Monitor.Exit(this);
try
{
connector = new NpgsqlConnector(conn)
{
ClearCounter = _clearCounter
};
await connector.Open(timeout, async, cancellationToken);
Counters.NumberOfPooledConnections.Increment();
EnsureMinPoolSize(conn);
return(connector);
}
catch
{
lock (this)
DecrementBusy();
throw;
}
}
internal static Task <T> WithCancellationAndTimeout <T>(this Task <T> task, NpgsqlTimeout timeout, CancellationToken cancellationToken) => task.WithCancellation(cancellationToken).WithTimeout(timeout);
internal static Task WithCancellationAndTimeout(this Task task, NpgsqlTimeout timeout, CancellationToken cancellationToken)
{
return(task
.WithCancellation(cancellationToken)
.WithTimeout(timeout));
}
internal async Task <List <PostgresType> > LoadBackendTypes(NpgsqlConnection conn, NpgsqlTimeout timeout, bool async)
{
var commandTimeout = 0; // Default to infinity
if (timeout.IsSet)
{
commandTimeout = (int)timeout.TimeLeft.TotalSeconds;
if (commandTimeout <= 0)
{
throw new TimeoutException();
}
}
var typeLoadingQuery = GenerateTypesQuery(SupportsRangeTypes, SupportsEnumTypes, conn.Settings.LoadTableComposites);
using (var command = new NpgsqlCommand(typeLoadingQuery, conn))
{
command.CommandTimeout = commandTimeout;
command.AllResultTypesAreUnknown = true;
using (var reader = async ? await command.ExecuteReaderAsync() : command.ExecuteReader())
{
var byOID = new Dictionary <uint, PostgresType>();
// First load the types themselves
while (async ? await reader.ReadAsync() : reader.Read())
{
timeout.Check();
var ns = reader.GetString(reader.GetOrdinal("nspname"));
var internalName = reader.GetString(reader.GetOrdinal("typname"));
var oid = Convert.ToUInt32(reader[reader.GetOrdinal("oid")]);
Debug.Assert(internalName != null);
Debug.Assert(oid != 0);
var typeChar = reader.GetString(reader.GetOrdinal("type"))[0];
switch (typeChar)
{
case 'b': // Normal base type
var baseType = new PostgresBaseType(ns, internalName, oid);
byOID[baseType.OID] = baseType;
continue;
case 'a': // Array
{
var elementOID = Convert.ToUInt32(reader[reader.GetOrdinal("elemoid")]);
Debug.Assert(elementOID > 0);
if (!byOID.TryGetValue(elementOID, out var elementPostgresType))
{
Log.Trace($"Array type '{internalName}' refers to unknown element with OID {elementOID}, skipping", conn.ProcessID);
continue;
}
var arrayType = new PostgresArrayType(ns, internalName, oid, elementPostgresType);
byOID[arrayType.OID] = arrayType;
continue;
}
case 'r': // Range
{
var elementOID = Convert.ToUInt32(reader[reader.GetOrdinal("elemoid")]);
Debug.Assert(elementOID > 0);
if (!byOID.TryGetValue(elementOID, out var subtypePostgresType))
{
Log.Trace($"Range type '{internalName}' refers to unknown subtype with OID {elementOID}, skipping", conn.ProcessID);
continue;
}
var rangeType = new PostgresRangeType(ns, internalName, oid, subtypePostgresType);
byOID[rangeType.OID] = rangeType;
continue;
}
case 'e': // Enum
var enumType = new PostgresEnumType(ns, internalName, oid);
byOID[enumType.OID] = enumType;
continue;
case 'c': // Composite
// Unlike other types, we don't
var compositeType = new PostgresCompositeType(ns, internalName, oid);
byOID[compositeType.OID] = compositeType;
continue;
case 'd': // Domain
var baseTypeOID = Convert.ToUInt32(reader[reader.GetOrdinal("typbasetype")]);
Debug.Assert(baseTypeOID > 0);
if (!byOID.TryGetValue(baseTypeOID, out var basePostgresType))
{
Log.Trace($"Domain type '{internalName}' refers to unknown base type with OID {baseTypeOID}, skipping", conn.ProcessID);
continue;
}
var domainType = new PostgresDomainType(ns, internalName, oid, basePostgresType);
byOID[domainType.OID] = domainType;
continue;
case 'p': // pseudo-type (record, void)
// Hack this as a base type
goto case 'b';
default:
throw new ArgumentOutOfRangeException($"Unknown typtype for type '{internalName}' in pg_type: {typeChar}");
}
}
if (async)
{
await reader.NextResultAsync();
}
else
{
reader.NextResult();
}
LoadCompositeFields(reader, byOID);
if (SupportsEnumTypes)
{
if (async)
{
await reader.NextResultAsync();
}
else
{
reader.NextResult();
}
LoadEnumLabels(reader, byOID);
}
return(byOID.Values.ToList());
}
}
}
internal NpgsqlConnector Allocate(NpgsqlConnection conn, NpgsqlTimeout timeout)
{
NpgsqlConnector connector;
Monitor.Enter(this);
while (Idle.Count > 0)
{
connector = Idle.Pop();
// An idle connector could be broken because of a keepalive
if (connector.IsBroken)
{
continue;
}
connector.Connection = conn;
Busy++;
EnsurePruningTimerState();
Monitor.Exit(this);
return(connector);
}
Contract.Assert(Busy <= _max);
if (Busy == _max)
{
// TODO: Async cancellation
var tcs = new TaskCompletionSource <NpgsqlConnector>();
EnqueueWaitingOpenAttempt(tcs);
Monitor.Exit(this);
try
{
WaitForTask(tcs.Task, timeout.TimeLeft);
}
catch
{
// We're here if the timeout expired or the cancellation token was triggered
// Re-lock and check in case the task was set to completed after coming out of the Wait
lock (this)
{
if (!tcs.Task.IsCompleted)
{
tcs.SetCanceled();
throw;
}
}
}
connector = tcs.Task.Result;
connector.Connection = conn;
return(connector);
}
// No idle connectors are available, and we're under the pool's maximum capacity.
Busy++;
Monitor.Exit(this);
try
{
connector = new NpgsqlConnector(conn)
{
ClearCounter = _clearCounter
};
connector.Open(timeout);
EnsureMinPoolSize(conn);
return(connector);
}
catch
{
lock (this)
Busy--;
throw;
}
}
static CancellationToken GetCombinedCancellationToken(ref CancellationTokenSource?combinedCts, NpgsqlTimeout timeout, CancellationToken cancellationToken)
{
var finalCt = cancellationToken;
if (timeout.IsSet)
{
combinedCts = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken);
combinedCts.CancelAfter((int)timeout.CheckAndGetTimeLeft().TotalMilliseconds);
finalCt = combinedCts.Token;
}
return(finalCt);
}
internal static async Task <TResult> ExecuteWithTimeout <TResult>(Func <CancellationToken, Task <TResult> > func, NpgsqlTimeout timeout, CancellationToken cancellationToken)
{
CancellationTokenSource?combinedCts = null;
try
{
var combinedCancellationToken = GetCombinedCancellationToken(ref combinedCts, timeout, cancellationToken);
return(await func(combinedCancellationToken));
}
finally
{
combinedCts?.Dispose();
}
}
static async Task <AvailablePostgresTypes> LoadBackendTypes(NpgsqlConnector connector, NpgsqlTimeout timeout, bool async)
{
var commandTimeout = 0; // Default to infinity
if (timeout.IsSet)
{
commandTimeout = (int)timeout.TimeLeft.TotalSeconds;
if (commandTimeout <= 0)
{
throw new TimeoutException();
}
}
var types = new AvailablePostgresTypes();
using (var command = new NpgsqlCommand(connector.SupportsRangeTypes ? TypesQueryWithRange : TypesQueryWithoutRange, connector.Connection))
{
command.CommandTimeout = commandTimeout;
command.AllResultTypesAreUnknown = true;
using (var reader = async ? await command.ExecuteReaderAsync() : command.ExecuteReader())
{
while (async ? await reader.ReadAsync() : reader.Read())
{
timeout.Check();
LoadBackendType(reader, types, connector);
}
}
}
return(types);
}
public Task <NpgsqlDatabaseInfo?> Load(NpgsqlConnection conn, NpgsqlTimeout timeout, bool async)
=> Task.FromResult(
new NpgsqlConnectionStringBuilder(conn.ConnectionString).ServerCompatibilityMode == ServerCompatibilityMode.NoTypeLoading
? (NpgsqlDatabaseInfo) new PostgresMinimalDatabaseInfo(conn)
: null
);
public Task <NpgsqlDatabaseInfo?> Load(NpgsqlConnector conn, NpgsqlTimeout timeout, bool async)
=> Task.FromResult(
conn.Settings.ServerCompatibilityMode == ServerCompatibilityMode.NoTypeLoading
? (NpgsqlDatabaseInfo) new PostgresMinimalDatabaseInfo(conn)
: null
);
