/// <summary>
/// Creates a specific topic if it doesn't exist in the target namespace.
/// </summary>
/// <param name="sbNamespace">The <see cref="IServiceBusNamespace"/> where we are creating the topic in.</param>
/// <param name="name">The name of the topic that we are looking for.</param>
/// <returns>The <see cref="ITopic"/> entity object that references the Azure topic.</returns>
public static async Task <ITopic> CreateTopicIfNotExists(this IServiceBusNamespace sbNamespace, string name)
{
var topic = await sbNamespace.GetTopicByNameAsync(name);
if (topic != null)
{
return(topic);
}
try
{
return(await sbNamespace.Topics
.Define(name.ToLowerInvariant())
.WithDuplicateMessageDetection(TimeSpan.FromMinutes(10))
.CreateAsync());
}
catch (CloudException ce)
when(ce.Response.StatusCode == HttpStatusCode.BadRequest &&
ce.Message.Contains("SubCode=40000. The value for the requires duplicate detection property of an existing Topic cannot be changed"))
{
// Create topic race condition occurred. Return existing topic.
return(await sbNamespace.GetTopicByNameAsync(name));
}
}
