public async Task <DbCommandProxy> CreateCommandAsync(ConnectionFactoryParameters parameters, ICommandMetricsReportable?metricsReporter, CancellationToken cancellationToken)
{
var(connection, index, payOutNumber) = await this._pool.GetConnectionAsync(
parameters,
_maxExecutionTime,
nameof(GlobalConnectionPoolStrategy),
cancellationToken)
.ConfigureAwait(false);
//ChangeDatabase はあまり対応したくない感じだけど、一応指定されてたらここで反映しよう。
if (!string.IsNullOrWhiteSpace(this._overriddenDatabaseName) && connection.Connection.Database != this._overriddenDatabaseName)
{
await connection.Connection.ChangeDatabaseAsync(this._overriddenDatabaseName, cancellationToken).ConfigureAwait(false);
}
var sourceCommand = connection.Connection.CreateCommand();
var command = new DbCommandProxy(
connection.Id,
sourceCommand,
metricsReporter,
x =>
{
this._workingCommands.TryRemove(x, out _);
this._pool.ReleaseConnection(index, payOutNumber);
});
this._workingCommands.TryAdd(command, true);
return(command);
}
public void Test()
{
IDbCommand command = new DbCommandProxy();
command.CommandText = "SELECT COUNT(*) FROM Person.Address WHERE 1 = 0";
Assert.AreEqual <int>(0, (int)command.ExecuteScalar());
}
private void OnCommandCompleted(DbCommandProxy command)
{
//Get initial connection because DbCommandProxy.Connection is mutable.
if (!this._workingCommands.TryRemove(command, out var connection))
{
return;
}
lock (this._reusableConnectionsLock)
{
this._reusableConnections.Add(connection);
}
//fire and forget.
Task.Run(async() =>
{
await Task.Delay(this._reusableTime).ConfigureAwait(false);
bool removable;
lock (this._reusableConnectionsLock)
{
removable = this._reusableConnections.Remove(connection);
}
if (removable)
{
connection.Dispose();
}
});
}
public async Task <DbCommandProxy> CreateCommandAsync(ConnectionFactoryParameters parameters,
ICommandMetricsReportable?metricsReporter,
CancellationToken cancellationToken)
{
var connection = this.TryReuse();
if (connection == null)
{
connection = this._factory.CreateConnection(parameters);
await connection.Connection.OpenAsync(cancellationToken).ConfigureAwait(false);
if (!string.IsNullOrWhiteSpace(this._overriddenDatabaseName))
{
connection.Connection.ChangeDatabase(this._overriddenDatabaseName !);
}
}
var command = new DbCommandProxy(
connection.Id,
connection.Connection.CreateCommand(),
metricsReporter,
this.OnCommandCompleted);
this._workingCommands.TryAdd(command, connection);
return(command);
}
private void OnCommandCompleted(DbCommandProxy command)
{
lock (this._commandQueueLock)
{
if (this._commandPreparerQueue.Count > 0)
{
var preparer = this._commandPreparerQueue.Dequeue();
preparer.SetResult(true);
}
else
{
this._isCommandExecuting = false;
}
}
}
public void Test()
{
IDbCommand command = new DbCommandProxy();
command.CommandText = "SELECT COUNT(*) FROM Person.Address WHERE 1 = 0";
Assert.AreEqual <int>(0, (int)command.ExecuteScalar());
// 确认是否缓冲机制已经生效
Assert.AreEqual <int>(1, ((DbCommandProxy)command).CacheCount);
command.ExecuteScalar();
// 确认在执行内容不发生变化的情况下，是否代理可以用到缓冲
Assert.AreEqual <int>(1, ((DbCommandProxy)command).CacheCount);
// 修正执行SQL
command.CommandText = "SELECT COUNT(*) FROM Person.Address";
int firstValue = (int)command.ExecuteScalar();
// 检查修正执行 SQL 后的缓冲加载情况
Assert.AreEqual <int>(2, ((DbCommandProxy)command).CacheCount);
command.CommandText = "SELECT COUNT(*) FROM Person.Address WHERE 1 = 1";
command.ExecuteScalar();
// 确认数据缓冲代理的自动更新机制
Assert.AreEqual <int>(2, ((DbCommandProxy)command).CacheCount);
}
public async Task <DbCommandProxy> CreateCommandAsync(ConnectionFactoryParameters parameters,
ICommandMetricsReportable metricsReporter,
CancellationToken cancellationToken)
{
var preparer = new TaskCompletionSource <bool>();
lock (this._commandQueueLock)
{
if (!this._isCommandExecuting)
{
this._isCommandExecuting = true;
preparer.SetResult(true);
}
else
{
this._commandPreparerQueue.Enqueue(preparer);
}
}
await preparer.Task.ConfigureAwait(false);
var connection = await this.GetConnectionAsync(parameters, cancellationToken).ConfigureAwait(false);
var sourceCommand = connection.Connection.CreateCommand();
if (this._transaction != null)
{
sourceCommand.Transaction = this._transaction;
}
var command = new DbCommandProxy(
connection.Id,
sourceCommand,
metricsReporter,
this.OnCommandCompleted);
return(command);
}
public DbTransaction GetTransactionOrNull(DbCommandProxy command) => this._transaction;
public DbConnection GetConnectionOrNull(DbCommandProxy command) => this._connection?.ConnectionWithId.Connection;
public DbConnection GetConnectionOrNull(DbCommandProxy command)
{
//Command.Connection の差し替えには対応しない。
throw new NotSupportedException();
}
public DbConnection?GetConnectionOrNull(DbCommandProxy command)
{
return(this._workingCommands.TryGetValue(command, out var connection) ? connection.Connection : null);
}
