private static Polly.Retry.AsyncRetryPolicy GetWaitAndRetry(EventReliabilitySettings eventReliabilitySettings)
{
return(Policy
.Handle <Exception>()
.WaitAndRetryAsync(
(int)(eventReliabilitySettings?.RetryAttempts).GetValueOrDefault(),
retryAttempt => eventReliabilitySettings?.RetrySleepDuration ?? TimeSpan.FromSeconds(0)));
}
/// <summary>
/// Add EventHub publisher with IoC.
/// </summary>
/// <exception cref="ArgumentException">When <paramref name="eventName"/> or <paramref name="connectionString"/> is null, empty or invalid.</exception>
/// <exception cref="ArgumentNullException"><paramref name="connectionString"/> is invalid.</exception>
/// <param name="services"><see cref="IServiceCollection"/> injection.</param>
/// <param name="eventName">EventHub name.</param>
/// <param name="connectionString">EventHub connection string with format: Endpoint=sb://namespace_DNS_Name;SharedAccessKeyName=SHARED_ACCESS_KEY_NAME;SharedAccessKey=SHARED_ACCESS_KEY;EntityPath=.</param>
/// <param name="reliabilitySettings">Event reliability settings.</param>
/// <returns><see cref="IServiceCollection"/> with EventHub plugin injected.</returns>
public static IServiceCollection AddEventHubPlugin(
this IServiceCollection services,
string eventName,
string connectionString,
EventReliabilitySettings reliabilitySettings = null)
{
services.AddEventPlugin(eventName, new AzureEventHub(connectionString, eventName, reliabilitySettings));
return(services);
}
/// <summary>
/// Start event hub process.
/// </summary>
/// <param name="serverlessLogger">Logger to save log.</param>
/// <param name="logger">Logger to be injected in <paramref name="serverlessLogger"/>.</param>
/// <param name="patternLog">Pattern log.</param>
/// <param name="events">Events to be processed.</param>
/// <param name="processEventAsync">Process with business rules to be processed.</param>
/// <param name="publishPoisonedEventAsync">Function receiving error parameter to publish poisoned event data.</param>
/// <param name="eventReliabilitySettings">Event reliability settings.</param>
/// <returns>Task executed.</returns>
public static async Task StartEventProcessAsync(
IServerlessLogger serverlessLogger,
ILogger logger,
string patternLog,
EventData[] events,
Func <EventData, Task> processEventAsync,
Func <EventData, Exception, Task> publishPoisonedEventAsync,
EventReliabilitySettings eventReliabilitySettings)
{
try
{
serverlessLogger.InjectLogger(logger);
if (events.Length == 0)
{
serverlessLogger.LogWarning($"{patternLog} No event to process.");
return;
}
serverlessLogger.LogInformation($"{patternLog} Start processing...");
var waitAndRetryAsync = GetWaitAndRetry(eventReliabilitySettings);
var eventCount = events.Length;
for (int eventIndex = 0; eventIndex < eventCount; eventIndex++)
{
serverlessLogger.LogInformation($"{patternLog} Processing event index {eventIndex}...");
var eventData = events[eventIndex];
var fallbackAsync = GetFallback(serverlessLogger, patternLog, eventData, publishPoisonedEventAsync);
await Policy
.WrapAsync(fallbackAsync, waitAndRetryAsync)
.ExecuteAsync(() => processEventAsync(eventData))
.ConfigureAwait(false);
serverlessLogger.LogInformation($"{patternLog} Event index {eventIndex} processed!");
}
serverlessLogger.LogInformation($"{patternLog} Processing completed!");
}
catch (Exception ex)
{
serverlessLogger.LogError(ex, $"{patternLog} Processing failed!");
throw;
}
}
/// <summary>
/// Initializes a new instance of the <see cref="AzureEventHub"/> class.
/// </summary>
/// <exception cref="ArgumentException">When <paramref name="connectionString"/> is null, empty or invalid.</exception>
/// <exception cref="ArgumentException">When <paramref name="eventName"/> is null, empty or invalid.</exception>
/// <param name="connectionString">EventHub connection string with format: Endpoint=sb://namespace_DNS_Name;EntityPath=EVENT_HUB_NAME;SharedAccessKeyName=SHARED_ACCESS_KEY_NAME;SharedAccessKey=SHARED_ACCESS_KEY.</param>
/// <param name="eventName">EventHub name to set EntityPath.</param>
/// <param name="reliabilitySettings">Event reliability settings.</param>
public AzureEventHub(string connectionString, string eventName, EventReliabilitySettings reliabilitySettings = null)
{
if (string.IsNullOrWhiteSpace(connectionString))
{
throw new ArgumentException(Messages.REQUIRED_PARAMETER, nameof(connectionString));
}
if (string.IsNullOrWhiteSpace(eventName))
{
throw new ArgumentException(Messages.REQUIRED_PARAMETER, nameof(eventName));
}
var connectionStringBuilder = new EventHubsConnectionStringBuilder(connectionString)
{
TransportType = TransportType.AmqpWebSockets,
EntityPath = eventName
};
eventHubClient = EventHubClient.CreateFromConnectionString(connectionStringBuilder.ToString());
ReliabilitySettings = reliabilitySettings;
}
