public InterceptionResult <int> SavingChanges(
DbContextEventData eventData,
InterceptionResult <int> result)
{
_audit = CreateAudit(eventData.Context);
using (var auditContext = new AuditContext(_connectionString))
{
auditContext.Add(_audit);
auditContext.SaveChanges();
}
return(result);
}
public async ValueTask <InterceptionResult <int> > SavingChangesAsync(
DbContextEventData eventData,
InterceptionResult <int> result,
CancellationToken cancellationToken = default)
{
_audit = CreateAudit(eventData.Context);
using (var auditContext = new AuditContext(_connectionString))
{
auditContext.Add(_audit);
await auditContext.SaveChangesAsync();
}
return(result);
}
private static SaveChangesAudit CreateAudit(DbContext context)
{
context.ChangeTracker.DetectChanges();
var audit = new SaveChangesAudit {
AuditId = Guid.NewGuid(), StartTime = DateTime.UtcNow
};
foreach (var entry in context.ChangeTracker.Entries())
{
var auditMessage = entry.State switch
{
EntityState.Deleted => CreateDeletedMessage(entry),
EntityState.Modified => CreateModifiedMessage(entry),
EntityState.Added => CreateAddedMessage(entry),
_ => null
};
if (auditMessage != null)
{
audit.Entities.Add(new EntityAudit {
State = entry.State, AuditMessage = auditMessage
});
}
}
return(audit);
string CreateAddedMessage(EntityEntry entry)
=> entry.Properties.Aggregate(
$"Inserting {entry.Metadata.DisplayName()} with ",
(auditString, property) => auditString + $"{property.Metadata.Name}: '{property.CurrentValue}' ");
string CreateModifiedMessage(EntityEntry entry)
=> entry.Properties.Where(property => property.IsModified || property.Metadata.IsPrimaryKey())
.Aggregate(
$"Updating {entry.Metadata.DisplayName()} with ",
(auditString, property) =>
auditString + $"{property.Metadata.Name}: '{property.CurrentValue}' ");
string CreateDeletedMessage(EntityEntry entry)
=> entry.Properties.Where(property => property.Metadata.IsPrimaryKey()).Aggregate(
$"Deleting {entry.Metadata.DisplayName()} with ",
(auditString, property) => auditString + $"{property.Metadata.Name}: '{property.CurrentValue}' ");
}
}
