/// <summary>
/// Called when the dialog is started and pushed onto the dialog stack.
/// </summary>
/// <param name="dc">The <see cref="DialogContext"/> for the current turn of conversation.</param>
/// <param name="options">Optional, initial information to pass to the dialog.</param>
/// <param name="cancellationToken">A cancellation token that can be used by other objects
/// or threads to receive notice of cancellation.</param>
/// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
public override async Task <DialogTurnResult> BeginDialogAsync(DialogContext dc, object options = null, CancellationToken cancellationToken = default(CancellationToken))
{
if (options is CancellationToken)
{
throw new ArgumentException($"{nameof(options)} cannot be a cancellation token");
}
if (this.Disabled != null && this.Disabled.GetValue(dc.State))
{
return(await dc.EndDialogAsync(cancellationToken : cancellationToken).ConfigureAwait(false));
}
if (dc.Context.Activity.ChannelId != Channels.Msteams)
{
throw new InvalidOperationException($"{Kind} works only on the Teams channel.");
}
string meetingId = MeetingId.GetValueOrNull(dc.State);
string participantId = ParticipantId.GetValueOrNull(dc.State);
string tenantId = TenantId.GetValueOrNull(dc.State);
if (participantId == null)
{
// TeamsInfo.GetMeetingParticipantAsync will default to retrieving the current meeting's participant
// if none is provided. This could lead to unexpected results. Therefore, GetMeetingParticipant action
// throws an exception if the expression provided somehow maps to an invalid result.
throw new InvalidOperationException($"{Kind} could not determine the participant id by expression value provided. {nameof(participantId)} is required.");
}
var result = await TeamsInfo.GetMeetingParticipantAsync(dc.Context, meetingId, participantId, tenantId, cancellationToken : cancellationToken).ConfigureAwait(false);
if (this.Property != null)
{
dc.State.SetValue(this.Property.GetValue(dc.State), result);
}
return(await dc.EndDialogAsync(result, cancellationToken : cancellationToken).ConfigureAwait(false));
}
