private static async Task PopulateResourceEventData(
IResourceEventRepository resourceEventRepository,
ApiOperationContext context,
ResourceEvent resourceEvent)
{
// Get the latest after creation or update (cannot, obviously, get for a deleted record)
if (resourceEvent.ChangeType != ResourceEventChangeType.Deleted)
{
resourceEvent.Data = await GetByIdAsync(context, resourceEvent.SelfQuery);
}
if (resourceEvent.ChangeType == ResourceEventChangeType.Updated)
{
var previousResource =
await resourceEventRepository.GetCurrentDataAsync(resourceEvent.Href, resourceEvent.ResourceType);
// There are cases where the old resource will not exist because resources being saved was a new
// introduction after being in prod for over a year
if (previousResource != null)
{
resourceEvent.ChangedValues = ObjectComparer.GetPreviousValues(
previousResource,
resourceEvent.Data);
}
}
}
public static async Task HandleAsync(
IResourceEventRepository resourceEventRepository,
IApiLinkGenerator apiLinkGenerator,
ApiOperationContext context,
OperationResult result)
{
if (result is OkResult okResult)
{
var innerResult = okResult.Content;
if (innerResult is ResourceEvent resourceEvent)
{
var logger = context.ServiceProvider.GetRequiredService <ILogger <ResourceEventHandlerMiddlewareBuilder> >();
void AddMetadata(string k, object v) => resourceEvent.Metadata[k] = v;
context.UserAuthorisationContext?.PopulateMetadata(AddMetadata);
resourceEvent.CorrelationId = context.Activity?.Id;
resourceEvent.Operation = context.Operation;
var metadataProviders = context.ServiceProvider.GetServices <IContextMetadataProvider>();
foreach (var p in metadataProviders)
{
await p.PopulateMetadataAsync(context, AddMetadata);
}
// If we do not already have Data use the "SelfQuery" to populate using a nested query if possible
if (resourceEvent.Data == null && resourceEvent.SelfQuery != null)
{
await TryPopulateResourceEventDataAsync(context, resourceEvent);
}
var selfLink = context.DataModel.GetLinkFor(resourceEvent.ResourceType, "self");
if (selfLink == null)
{
logger.LogWarning(
"No self link exists. Href property of the resource event of type {ResourceType} will not be populated",
resourceEvent.ResourceType);
}
else
{
resourceEvent.Href = apiLinkGenerator.CreateUrl(selfLink, resourceEvent.Data ?? resourceEvent.SelfQuery);
}
if (resourceEvent.Data != null)
{
await TryPopulateChangedValuesAsync(resourceEventRepository, resourceEvent);
}
await resourceEventRepository.AddAsync(resourceEvent);
}
}
}
public static async Task HandleAsync(
IResourceEventRepository resourceEventRepository,
IApiLinkGenerator apiLinkGenerator,
ApiOperationContext context,
OperationResult result)
{
if (result is OkResult okResult)
{
var innerResult = okResult.Content;
if (innerResult is ResourceEvent resourceEvent)
{
var logger = context.ServiceProvider.GetRequiredService <ILogger <ResourceEventHandlerMiddlewareBuilder> >();
logger.LogDebug("ResourceEvent found. Loading resource. resource_type={0}", resourceEvent.ResourceType);
void AddMetadata(string k, object v) => resourceEvent.Metadata[k] = v;
context.UserAuthorisationContext?.PopulateMetadata(AddMetadata);
resourceEvent.CorrelationId = Activity.Current?.Id;
resourceEvent.Operation = context.Operation;
var metadataProviders = context.ServiceProvider.GetServices <IContextMetadataProvider>();
foreach (var p in metadataProviders)
{
await p.PopulateMetadataAsync(context, AddMetadata);
}
var selfLink = context.DataModel.GetLinkFor(resourceEvent.ResourceType, "self");
if (selfLink == null)
{
logger.LogWarning(
"No self link exists. Link and payload will not be populated. resource_type={0}",
resourceEvent.ResourceType.Name);
return;
}
resourceEvent.Href = apiLinkGenerator.CreateUrl(selfLink, resourceEvent.SelfQuery);
await PopulateResourceEventData(resourceEventRepository, context, resourceEvent);
await resourceEventRepository.AddAsync(resourceEvent);
}
}
}
private static async Task TryPopulateChangedValuesAsync(
IResourceEventRepository resourceEventRepository,
ResourceEvent resourceEvent)
{
if (resourceEvent.ChangeType == ResourceEventChangeType.Updated && resourceEvent.Data != null)
{
var previousResource =
await resourceEventRepository.GetCurrentDataAsync(resourceEvent.Href, resourceEvent.Data.GetType());
// There are cases where the old resource will not exist because resources being saved was a new
// introduction after being in prod for over a year
if (previousResource != null)
{
resourceEvent.ChangedValues = ObjectComparer.GetPreviousValues(
previousResource,
resourceEvent.Data);
}
}
}
