internal virtual ITask Finally <T>(T continuation)
where T : ITask
{
Guard.ArgumentNotNull(continuation, "continuation");
continuation.SetDependsOn(this);
this.continuation = (TaskBase)(object)continuation;
this.continuationAlways = true;
DependsOn?.SetFaultHandler((TaskBase)(object)continuation);
return(continuation);
}
internal virtual ITask Finally <T>(T taskToContinueWith)
where T : TaskBase
{
Guard.ArgumentNotNull(taskToContinueWith, nameof(taskToContinueWith));
continuation = (TaskBase)(object)taskToContinueWith;
continuationAlways = true;
continuation.SetDependsOn(this);
DependsOn?.SetFaultHandler((TaskBase)(object)continuation);
return(continuation);
}
protected TaskBase GetTopMostTask(TaskBase ret, bool onlyCreatedState)
{
ret = (!onlyCreatedState || Task.Status == TaskStatus.Created ? this : ret);
var depends = DependsOn;
if (depends == null)
{
return(ret);
}
return(depends.GetTopMostTask(ret, onlyCreatedState));
}
protected void SetContinuation(TaskBase continuation, TaskContinuationOptions runOptions)
{
Token.ThrowIfCancellationRequested();
Task.ContinueWith(_ =>
{
Token.ThrowIfCancellationRequested();
((TaskBase)(object)continuation).Schedule();
},
Token,
runOptions,
TaskManager.GetScheduler(continuation.Affinity));
}
/// <summary>
/// This does not set a dependency between the two tasks. Instead,
/// the Start method grabs the state of the previous task to pass on
/// to the next task via previousSuccess and previousException
/// </summary>
/// <param name="handler"></param>
internal void SetFaultHandler(TaskBase handler)
{
Task.ContinueWith(t =>
{
Token.ThrowIfCancellationRequested();
handler.Start(t);
},
Token,
TaskContinuationOptions.OnlyOnFaulted,
TaskManager.GetScheduler(handler.Affinity));
DependsOn?.SetFaultHandler(handler);
}
public virtual T Then <T>(T cont, bool always = false)
where T : ITask
{
Guard.ArgumentNotNull(cont, nameof(cont));
var taskBase = ((TaskBase)(object)cont);
var firstTaskBase = taskBase.GetTopMostTask() ?? taskBase;
firstTaskBase.SetDependsOn(this);
this.continuation = firstTaskBase;
this.continuationAlways = always;
return(cont);
}
protected TaskBase GetTopMostTask(TaskBase ret, bool onlyCreated, bool onlyUnstartedChain)
{
ret = (!onlyCreated || Task.Status == TaskStatus.Created ? this : ret);
var depends = DependsOn;
if (depends == null)
{
// if we're at the top of the chain and the chain has already been started
// and we only care about unstarted chains, return null
if (onlyUnstartedChain && Task.Status != TaskStatus.Created)
{
return(null);
}
return(ret);
}
return(depends.GetTopMostTask(ret, onlyCreated, onlyUnstartedChain));
}
public virtual T Then <T>(T nextTask, TaskRunOptions runOptions = TaskRunOptions.OnSuccess)
where T : ITask
{
Guard.ArgumentNotNull(nextTask, nameof(nextTask));
var nextTaskBase = ((TaskBase)(object)nextTask);
// find the task at the top of the chain
nextTaskBase = nextTaskBase.GetTopMostTask() ?? nextTaskBase;
// make the next task dependent on this one so it can get values from us
nextTaskBase.SetDependsOn(this);
if (runOptions == TaskRunOptions.OnSuccess)
{
this.continuationOnSuccess = nextTaskBase;
// if there are fault handlers in the chain we're appending, propagate them
// up this chain as well
if (nextTaskBase.continuationOnFailure != null)
{
SetFaultHandler(nextTaskBase.continuationOnFailure);
}
else if (nextTaskBase.continuationOnAlways != null)
{
SetFaultHandler(nextTaskBase.continuationOnAlways);
}
if (nextTaskBase.catchHandler != null)
{
Catch(nextTaskBase.catchHandler);
}
if (nextTaskBase.finallyHandler != null)
{
Finally(nextTaskBase.finallyHandler);
}
}
else if (runOptions == TaskRunOptions.OnFailure)
{
this.continuationOnFailure = nextTaskBase;
DependsOn?.SetFaultHandler(nextTaskBase);
}
else
{
this.continuationOnAlways = nextTaskBase;
DependsOn?.SetFaultHandler(nextTaskBase);
}
return(nextTask);
}
public virtual T Then <T>(T nextTask, TaskRunOptions runOptions = TaskRunOptions.OnSuccess, bool taskIsTopOfChain = false)
where T : ITask
{
Guard.ArgumentNotNull(nextTask, nameof(nextTask));
var nextTaskBase = ((TaskBase)(object)nextTask);
// find the task at the top of the chain
if (!taskIsTopOfChain)
{
nextTaskBase = nextTaskBase.GetTopMostTask() ?? nextTaskBase;
}
// make the next task dependent on this one so it can get values from us
nextTaskBase.SetDependsOn(this);
var nextTaskFinallyHandler = nextTaskBase.finallyHandler;
if (runOptions == TaskRunOptions.OnSuccess)
{
this.continuationOnSuccess = nextTaskBase;
// if there are fault handlers in the chain we're appending, propagate them
// up this chain as well
if (nextTaskBase.continuationOnFailure != null)
{
SetFaultHandler(nextTaskBase.continuationOnFailure);
}
else if (nextTaskBase.continuationOnAlways != null)
{
SetFaultHandler(nextTaskBase.continuationOnAlways);
}
if (nextTaskBase.catchHandler != null)
{
Catch(nextTaskBase.catchHandler);
}
if (nextTaskFinallyHandler != null)
{
Finally(nextTaskFinallyHandler);
}
}
else if (runOptions == TaskRunOptions.OnFailure)
{
this.continuationOnFailure = nextTaskBase;
DependsOn?.Then(nextTaskBase, TaskRunOptions.OnFailure, true);
}
else
{
this.continuationOnAlways = nextTaskBase;
DependsOn?.SetFaultHandler(nextTaskBase);
}
// if the current task has a fault handler, attach it to the chain we're appending
if (finallyHandler != null)
{
TaskBase endOfChainTask = (TaskBase)nextTaskBase.GetEndOfChain();
while (endOfChainTask != this && endOfChainTask != null)
{
endOfChainTask.finallyHandler += finallyHandler;
endOfChainTask = endOfChainTask.DependsOn;
}
}
return(nextTask);
}
protected void SetContinuation(TaskBase continuation, TaskContinuationOptions runOptions)
{
Task.ContinueWith(_ => ((TaskBase)(object)continuation).Run(), Token,
runOptions,
TaskManager.GetScheduler(continuation.Affinity));
}