/// <summary>
/// Executes the first child activity
/// </summary>
/// <param name="executionContext">The execution context of pipeline activity.</param>
protected override void Execute(NativeActivityContext executionContext)
{
int count = 0;
if (this.Activities != null)
{
count = this.Activities.Count;
}
if (count == 0)
{
throw new ArgumentException(ActivityResources.NoChildPipeline);
}
if (this.inputValidationFailed && Input != null && Input.Expression != null && this.Activities[0].Input != null && this.Activities[0].Input.Expression != null)
{
throw new ArgumentException(ActivityResources.DuplicateInputDefinedInPipeline);
}
if (this.resultValidationFailed && Result != null && Result.Expression != null && this.Activities[count - 1].Result != null && this.Activities[count - 1].Result.Expression != null)
{
throw new ArgumentException(ActivityResources.DuplicateResultDefinedInPipeline);
}
//Executing the first child activity.
PipelineEnabledActivity firstChild = this.Activities[0];
executionContext.ScheduleActivity(firstChild, new CompletionCallback(InternalExecute));
}
private void InternalExecute(NativeActivityContext executionContext, ActivityInstance completedInstance)
{
int completedInstanceIndex;
// Reading the value of pipeline activity variables from the context.
completedInstanceIndex = this.lastIndexHint.Get(executionContext);
PSDataCollection <PSObject> outValue = this.GetData(executionContext, this.OutputStream);
PSDataCollection <PSObject> inValue = this.GetData(executionContext, this.InputStream);
// Re-checking the index of the the child activity, which has just completed its execution.
if (completedInstanceIndex >= this.Activities.Count || this.Activities[completedInstanceIndex] != completedInstance.Activity)
{
completedInstanceIndex = this.Activities.IndexOf((PSActivity)completedInstance.Activity);
}
// Calculating next child activity.
int nextChildIndex = completedInstanceIndex + 1;
// Checking for pipeline activity completion.
if (nextChildIndex == this.Activities.Count)
{
if (inValue != null)
{
inValue.Dispose();
}
if (outValue != null)
{
outValue.Dispose();
}
return;
}
// Setting up the environment for next child activity to run.
if (outValue != null)
{
outValue.Complete();
}
if (inValue != null)
{
inValue.Dispose();
}
inValue = outValue;
outValue = new PSDataCollection <PSObject>();
// The pipeline is complete if there is no input
// PS > function foo { $input | Write-Output "Hello" }
// PS > foo
// PS >
if ((inValue == null) || (inValue.Count == 0))
{
if (outValue != null)
{
outValue.Dispose();
}
return;
}
this.SetData(executionContext, this.OutputStream, outValue);
this.SetData(executionContext, this.InputStream, inValue);
// Executing the next child activity.
PipelineEnabledActivity nextChild = this.Activities[nextChildIndex];
executionContext.ScheduleActivity(nextChild, new CompletionCallback(InternalExecute));
this.lastIndexHint.Set(executionContext, nextChildIndex);
}
