/// <summary>
/// Builds a set of tasks to perform the load.
/// </summary>
/// <returns>A sequence of tasks to execute.</returns>
private static IEnumerable<ITask> BuildTasks()
{
List<ITask> tasks = new List<ITask>();
var targetFactory = Program.connectionFactories["target"];
if (Program.Options.FullLoad)
{
// Clean out the database.
var cleanTask = new SequentialTask(
"Clean Target Database",
new ExecuteSqlTask("Truncate Facts", targetFactory, SqlQueries.TruncateFactsSql),
new ExecuteSqlTask("Delete dimension data", targetFactory, SqlQueries.DeleteDimensionData));
tasks.Add(cleanTask);
}
var dimensionTasks = new List<ITask>();
if (Program.Options.FullLoad)
{
var currencyLoader = new CurrencyLoader(targetFactory);
dimensionTasks.Add(currencyLoader.Build());
var dateLoader = new DateLoader(targetFactory);
dimensionTasks.Add(dateLoader.Build());
var productLoader = new ProductLoader(targetFactory);
Program.Disposables.Add(productLoader);
dimensionTasks.Add(productLoader.Build());
}
tasks.Add(new ParallelTask("Load Dimensions", dimensionTasks));
return tasks;
}
/// <summary>
/// Executes the loader task sequence.
/// </summary>
/// <remarks>
/// Note: This executes the supplied list in sequence. If parallel
/// execution is needed then create ParallelTasks in this list.
/// </remarks>
/// <param name="tasks">A sequence of tasks to execute.</param>
/// <returns>A task representing the completion of this function.</returns>
private static async Task ExecuteAsync(IEnumerable<ITask> tasks)
{
var mainTask = new SequentialTask("Main", tasks);
var context = new TaskContext(Program.CancellationTokenSource);
await mainTask.VerifyAsync(context);
await mainTask.ExecuteAsync(context);
}
