/// <summary>
/// Registers and type for auditing.
/// </summary>
/// <param name="auditableEntityType">Type to audit, must implement IAuditableEntity.</param>
/// <param name="auditEntityType">Type of audit entity, must implement IAuditEntity.</param>
public static void RegisterAuditType(Type auditableEntityType, Type auditEntityType)
{
// Basic parameter validation.
if (auditableEntityType == null)
{
throw new ArgumentNullException("auditableEntityType");
}
if (auditTypes.ContainsKey(auditableEntityType))
{
throw new ArgumentException("Type already registered for auditing.", "auditableEntityType");
}
// Validate the entity.
var iface = auditableEntityType.GetInterface("IAuditableEntity");
if (iface == null)
{
throw new ArgumentException("Entity does implement IAuditableEntity", "auditableEntityType");
}
AuditTypeInfo info = new AuditTypeInfo {
EntityType = auditableEntityType, AuditEntityType = auditEntityType
};
// Validate the auditEntity
if (auditEntityType != null)
{
iface = auditEntityType.GetInterface("IAuditEntity");
if (iface == null)
{
throw new ArgumentException("Entity does implement IAuditEntity", "auditEntityType");
}
// Extract the list of properties to audit.
var properties = auditEntityType.GetProperties();
var entityProperties = auditableEntityType.GetProperties().ToDictionary(x => x.Name);
foreach (var property in properties)
{
if (entityProperties.ContainsKey(property.Name))
{
if (property.PropertyType == entityProperties[property.Name].PropertyType)
{
info.AuditProperties.Add(property.Name);
}
}
}
}
// Valid so register.
auditTypes.Add(auditableEntityType, info);
}
/// <summary>
/// Checks the destination object for complex types. Returns a list of fields that are complex types.
/// </summary>
/// <param name="auditTypeInfo"></param>
/// <param name="entityEntry"></param>
/// <returns></returns>
private ICollection <string> GetComplexTypes(AuditTypeInfo auditTypeInfo, DbEntityEntry entityEntry)
{
var returnValue = new List <string>();
foreach (string propertyName in auditTypeInfo.AuditProperties)
{
if (entityEntry.Property(propertyName).GetType().Name.Contains("DbComplexPropertyEntry"))
{
returnValue.Add(propertyName);
}
}
return(returnValue);
}
private IAuditEntity AuditEntity(DbEntityEntry entityEntry, AuditTypeInfo auditTypeInfo, DateTimeOffset auditDateTime, string user)
{
// Create audit entity.
DbSet set = this.Set(auditTypeInfo.AuditEntityType);
IAuditEntity auditEntity = set.Create() as IAuditEntity;
// Check audit entity for complex types.
var complexTypes = GetComplexTypes(auditTypeInfo, entityEntry);
//Instantiate complex types.
foreach (var field in complexTypes)
{
var property = auditEntity.GetType().GetProperty(field);
var entityType = property.PropertyType;
property.SetValue(auditEntity, Activator.CreateInstance(entityType));
}
//Attach audit Entity to the context.
set.Add(auditEntity);
// Copy the properties.
DbEntityEntry auditEntityEntry = this.Entry(auditEntity);
foreach (string propertyName in auditTypeInfo.AuditProperties)
{
auditEntityEntry.Property(propertyName).CurrentValue = entityEntry.Property(propertyName).OriginalValue;
}
// Set the audit columns.
auditEntityEntry.Property(AuditUpdatedColumnName).CurrentValue = auditDateTime;
auditEntityEntry.Property(AuditUserColumnName).CurrentValue = user;
auditEntityEntry.Property(AuditTypeColumnName).CurrentValue = entityEntry.State == EntityState.Modified ? "update" : "delete";
auditEntityEntry.Property(AuditSourceIdColumnName).CurrentValue = entityEntry.OriginalValues.GetValue <int>("Id");
return(auditEntity);
}
