public async Task<ActionResult> UpdateScholarshipItemAsync([FromBody] ScholarshipItem scholarshipItemToUpdate)
{
var scholarshipItem = await _scholarshipContext.ScholarshipItems.SingleOrDefaultAsync(i => i.Id == scholarshipItemToUpdate.Id);
if (scholarshipItem == null)
{
return NotFound(new { Message = $"Item with id {scholarshipItemToUpdate.Id} not found." });
}
var oldAmount = scholarshipItem.Amount;
var raiseScholarshipItemAmountChangedEvent = oldAmount != scholarshipItemToUpdate.Amount;
// Update current scholarshipItem
scholarshipItem = scholarshipItemToUpdate;
_scholarshipContext.ScholarshipItems.Update(scholarshipItem);
if (raiseScholarshipItemAmountChangedEvent) // Save scholarshipItem's data and publish integration event through the Event Bus if Amount has changed
{
//Create Integration Event to be published through the Event Bus
var amountChangedEvent = new ScholarshipItemAmountChangedIntegrationEvent(scholarshipItem.Id, scholarshipItemToUpdate.Amount, oldAmount);
// Achieving atomicity between original Scholarship database operation and the IntegrationEventLog thanks to a local transaction
await _scholarshipIntegrationEventService.SaveEventAndScholarshipContextChangesAsync(amountChangedEvent);
// Publish through the Event Bus and mark the saved event as published
await _scholarshipIntegrationEventService.PublishThroughEventBusAsync(amountChangedEvent);
}
else // Just save the updated scholarshipItem because the ScholarshipItem's Amount hasn't changed.
{
await _scholarshipContext.SaveChangesAsync();
}
return CreatedAtAction(nameof(ItemByIdAsync), new { id = scholarshipItemToUpdate.Id }, null);
}
public async Task SaveEventAndScholarshipContextChangesAsync(IntegrationEvent evt)
{
_logger.LogInformation("----- ScholarshipIntegrationEventService - Saving changes and integrationEvent: {IntegrationEventId}", evt.Id);
//Use of an EF Core resiliency strategy when using multiple DbContexts within an explicit BeginTransaction():
//See: https://docs.microsoft.com/en-us/ef/core/miscellaneous/connection-resiliency
await ResilientTransaction.New(_scholarshipContext).ExecuteAsync(async() =>
{
// Achieving atomicity between original scholarship database operation and the IntegrationEventLog thanks to a local transaction
await _scholarshipContext.SaveChangesAsync();
await _eventLogService.SaveEventAsync(evt, _scholarshipContext.Database.CurrentTransaction);
});
}
public async Task Handle(ApplicationStatusChangedToPaidIntegrationEvent @event)
{
using (LogContext.PushProperty("IntegrationEventContext", $"{@event.Id}-{Program.AppName}"))
{
_logger.LogInformation("----- Handling integration event: {IntegrationEventId} at {AppName} - ({@IntegrationEvent})", @event.Id, Program.AppName, @event);
//we're not blocking slots
foreach (var applicationSlotItem in @event.ApplicationSlotItems)
{
var scholarshipItem = _scholarshipContext.ScholarshipItems.Find(applicationSlotItem.ScholarshipItemId);
scholarshipItem.RemoveSlots(applicationSlotItem.Slots);
}
await _scholarshipContext.SaveChangesAsync();
}
}