Business Layer Management utils for Entity Framework 6
The goal of the BLM packages is to create a separate layer for authorization, interpretation and event distributing logic between your data access layer (usually EF6) and your controller layer.
You can use the EfRepository in the same way as you did with Entity Framework's DbSet, but it will take care about handling the custom logic you've implemented in your authorizers / listeners / interpreters.
MyDbContext db = new MyDbContext();
EfRepository<MyEntityType> repository = new EfRepository<MyEntityType>(db);
// Get the entities you're authorized to see
var myAuthorizedEntities = repository.Entities(MyUserIdentity);This is a custom class passed to the business logic functions with the following properties:
- IIdentity Identity - The user identity
- Task<IQueryable> GetAuthorizedEntitySetAsync - One specified authorized entity set
- IQueryable GetFullEntitySet - The unauthorized, full entity set (technically, EF's DbSet)
You can implement your own authorization for the entity types with them. The package supports these types of authorizers, you should derive from their abstracts:
Triggered, when a user gets the EfRepository's 'Entities' attribute
public class MyCollectionAuthorizer : AuthorizeCollection<MyEntity>
{
public override async Task<IQueryable<MyEntity>> AuthorizeCollectionAsync(IQueryable<MyEntity>
entities, IContextInfo ctx)
{
var myUser = ctx.Identity.GetMyUser();
if (user.IsAdmin)
{
return entities;
}
return entities.Where(r => r.IsPublic);
}
}Triggered on each entity, when a user calls Repository.Add/AddAsync/AddRange/AddRangeAsync and new entities when calling Repository.SaveChanges/SaveChangesAsync.
public class CreateAdminOnly : IAuthorizeCreate<ICreateAdminOnly>
{
public async Task<AuthorizationResult> CanCreateAsync(ICreateAdminOnly entity,
IContextInfo ctx)
{
if (ctx.Identity.GetTerUser().IsAdmin)
{
return AuthorizationResult.Success();
}
return AuthorizationResult.Fail($"Only admin users are authorized to create entity with type '{entity.GetType().FullName}'", entity);
}
}Triggered before modifying entity in the DB. Very similar to AuthorizeCreate, but the unchanged and the updated entity are both passed.
Triggered before deleting an entity from DB. Similar to AuthorizeCreate.
They are to change a simple property value on the entity, before saving to the DB, you can eliminate DB triggers (BeforeInsert, BeforeUpdate) with them.
public class CreatedByUserInterpreter : InterpretBeforeCreate<IHasCreator>
{
public override IHasCreator DoInterpret(IHasCreator entity, IContextInfo context)
{
var user = context.GetFullEntitySet<User>().FirstOrDefault(a => a.LoginName == context.Identity.Name);
entity.CreatedByUser = user;
return entity;
}
}
public class ModifiedByInterpreter : InterpretBeforeModify<IHasModifiedBy>
{
public override IHasModifiedBy DoInterpret(IHasModifiedBy originalEntity, IHasModifiedBy modifiedEntity, IContextInfo context)
{
var modifier = context.GetFullEntitySet<User>().FirstOrDefault(a => a.LoginName == context.Identity.Name);
modifiedEntity.ModifiedByUser = modifier;
return modifiedEntity;
}
}...Docs coming soon. :)
If you've implemented an authorizer/interpreter/event listener for a base class and you have a repository with the derived class, the authorizer/interpreter/listener will kick in when you use the derived repository as well. This works with interfaces also.