Wait for an event in a WaterfallDialog

Working on a Skill, I needed to block the execution of a WaterfallDialog while waiting for a specific event to arrive.
The solution is simple and based on the use of EventPrompt. Below I show how to use it.

Register EventPrompt in the constructor

AddDialog(new WaterfallDialog(nameof(WaterfallDialog), new WaterfallStep[]
{
	HelloAsync,
	WaitForEventAsync,
	DoneAsync
}));

AddDialog(new EventPrompt(nameof(EventPrompt), "SampleEvent", Validate));

InitialDialogId = nameof(WaterfallDialog);

Implement the three dialog steps

private async Task<DialogTurnResult> HelloAsync(WaterfallStepContext stepContext, CancellationToken cancellationToken)
{
	await stepContext.Context.SendActivityAsync(MessageFactory.Text("Hello :)"), cancellationToken);

	return await stepContext.NextAsync(cancellationToken);
}

private async Task<DialogTurnResult> WaitForEventAsync(WaterfallStepContext stepContext, CancellationToken cancellationToken)
{
	return await stepContext.PromptAsync(nameof(EventPrompt), new PromptOptions { Prompt = MessageFactory.Text("Waiting for the event") });
}

private async Task<DialogTurnResult> DoneAsync(WaterfallStepContext stepContext, CancellationToken cancellationToken)
{
	await stepContext.Context.SendActivityAsync(MessageFactory.Text("After I receive the event."), cancellationToken);

	return await stepContext.NextAsync(cancellationToken);
}

Implement the event validator

async Task<bool> Validate(PromptValidatorContext<Activity> promptContext, CancellationToken cancellationToken)
{
	var activity = promptContext.Recognized.Value;
	if (activity.Type == ActivityTypes.Event)
	{
		try
		{
			string eventValue = (string)activity.Value;
			
			if(eventValue == "OK")
			{
				return true;
			}
		}
		catch { }
	}

	return false;
}

Share data from Virtual Assistant to Skill

For some weeks I have been working on a project based on Bot Framework. Things were going well until I found myself in the position of having to share information between a Virtual Assistant and a Skill … Given that it gave me problems and that my requests made on Stackoverflow did not produce answers, I share the solution here.

This post expects the user to be clear what Virtual Assistant and Skill are and has already installed the prerequisites as described here:
https://microsoft.github.io/botframework-solutions/tutorials/csharp/create-assistant/1_intro/

Create a Virtual Assistant using the Virtual Assistant Template and name it SampleVirtualAssistant

Add to the solution SampleVirtualAssistant a new project (the Skill) using the Skill Template and name it SampleSkill

Rebuild the solution.

In the following example I’ll show the commands as execute on my system, where my sources path is C:\Users\emili\source\lab, be aware to replace it with your correct path!

Open PowerShell Core to execute the following commands.

Deploy to Azure the required resources.

cd c:\users\emili\source\lab\SampleVirtualAssistant\SampleVirtualAssistant\SampleVirtualAssistant
.\Deployment\Scripts\deploy.ps1
cd C:\Users\emili\source\lab\SampleVirtualAssistant\SampleSkill\SampleSkill
.\Deployment\Scripts\deploy.ps1

Now we go to work on the code.

In the project SampleSkill, edit the file manifestTemplate.json to add the required slot.

cd C:\users\emili\source\lab\SampleVirtualAssistant\SampleVirtualAssistant\SampleVirtualAssistant
botskills connect --botName SampleVirtualAssistant --remoteManifest "http://<your resource>.azurewebsites.net/api/skill/manifest" --luisFolder C:\Users\emili\source\lab\SampleVirtualAssistant\SampleSkill\SampleSkill\Deployment\Resources\LU\en\ --cs

In the project SampleVirtualAssistant edit the file skills.json to add the required slot.

In the project SampleVirtualAssistant edit the file MainDialog.cs to update the class Events

In the same file, in the method OnEventAsync add the code that handle the event to set the UserEmail

In the project SampleSkill, in the file MainDialog.cs in the RouteAsync method insert this code after the call to PopulateSateFromSemanticAcion

Rebuild all.

Publish the skill and the VA.

Start the chat and test it 🙂