Introduction

Organization units (OU) can be used to hierarchically group users and entities.

OrganizationUnit Entity

An OU is represented by the OrganizationUnit entity. Fundamental properties of this entity are;

• TenantId: Tenant's Id of this OU. Can be null for host OUs.
• ParentId: Parent OU's Id. Can be null if this is a root OU.
• Code: A hierarchical string code that is unique for a tenant.
• DisplayName: Shown name of the OU.

OrganizationUnit entitiy's primary key (Id) is long and it derives from FullAuditedEntity which provides audit information and implements ISoftDelete interface (so, OUs are not deleted from database, they are just marked as deleted).

Organization Tree

Since an OU can have a parent, all OUs of a tenant are in a tree structure. There are some rules for this tree;

• There can be more than one root (which have null ParentId).
• Maximum deep of tree is defined as a constant as OrganizationUnit.MaxDepth, which is 16.
• There is a limit for first-level children count of an OU (because of fixed OU Code unit length explained below).

OU Code

OU code is automatically generated and maintained by OrganizationUnit Manager. It's a string something like:

"00001.00042.00005"

This code can be used to easily query database for all children (recursively) of an OU. There are some rules for this code;

• It's unique for a tenant.
• All children of same OU have codes start with parent OU's code.
• It's fixed length based on level of OU in the tree, as shown in the sample.
• While OU code is unique, it can be changable if you move an OU. So, we should reference an OU by Id, not Code.

OrganizationUnit Manager

OrganizationUnitManager class can be injected and used to manage OUs. Common use cases are:

• Create, Update or Delete an OU
• Move an OU in OU tree.
• Getting information about OU tree and items.

Multi Tenancy

OrganizationUnitManager is designed to work for a single tenant in a time. It works for the current tenant as default.

Common Use Cases

Here, we will see common use cases for OUs. You can find source code of the samples here.

Creating Entity Belongs To An Organization Unit

Most obvious usage of OUs is to assign an entity to an OU. Let's see a sample entity:

public class Product : Entity, IMustHaveTenant, IMustHaveOrganizationUnit
{
    public virtual int TenantId { get; set; }

    public virtual long OrganizationUnitId { get; set; }
    
    public virtual string Name { get; set; }

    public virtual float Price { get; set; }
}

We simple created OrganizationUnitId property to assign this entity to an OU. IMustHaveOrganizationUnit defines the OrganizationUnitId property. We don't have to implement it, but it's suggested to provide standardization. There is also an IMayHaveOrganizationId which has a nullable OrganizationUnitId property.

Now, we can relate a Product to an OU and query products of a specific OU.

Notice that; Product entity have a TenantId (which is a property of IMustHaveTenant) to distinguish products of different tenants in a multi-tenant application (see multi tenancy document). If your application is not multi-tenant, you don't need this interface and property.

Get Entities In An Organization Unit

Getting Products of an OU is simple. Let's see this sample domain service:

public class ProductManager : IDomainService
{
    private readonly IRepository<Product> _productRepository;

    public ProductManager(IRepository<Product> productRepository)
    {
        _productRepository = productRepository;
    }

    public List<Product> GetProductsInOu(long organizationUnitId)
    {
        return _productRepository.GetAllList(p => p.OrganizationUnitId == organizationUnitId);
    }
				
}

We can simply write a predicate against Product.OrganizationUnitId as shown above.

Get Entities In An Organization Unit Including It's Child Organization Units

We may want to get Products of an organization unit including child organization units. In this case, OU Code can help us:

public class ProductManager : IDomainService
{
    private readonly IRepository<Product> _productRepository;
    private readonly IRepository<OrganizationUnit, long> _organizationUnitRepository;

    public ProductManager(
        IRepository<Product> productRepository, 
        IRepository<OrganizationUnit, long> organizationUnitRepository)
    {
        _productRepository = productRepository;
        _organizationUnitRepository = organizationUnitRepository;
    }

    [UnitOfWork]
    public virtual List<Product> GetProductsInOuIncludingChildren(long organizationUnitId)
    {
        var code = _organizationUnitRepository.Get(organizationUnitId).Code;

        var query =
            from product in _productRepository.GetAll()
            join organizationUnit in _organizationUnitRepository.GetAll() on product.OrganizationUnitId equals organizationUnit.Id
            where organizationUnit.Code.StartsWith(code)
            select product;

        return query.ToList();
    }
}

First, we got code of the given OU. Then we created a LINQ with a join and StartsWith(code) condition (StartsWith creates a LIKE query in SQL). Thus, we can hierarchically get products of an OU.

Filter Entities For A User

We may want to get all products those are in OUs of a specific user. Example code:

public class ProductManager : IDomainService
{
    private readonly IRepository<Product> _productRepository;
    private readonly UserManager _userManager;

    public ProductManager(
        IRepository<Product> productRepository, 
        UserManager userManager)
    {
        _productRepository = productRepository;
        _organizationUnitRepository = organizationUnitRepository;
        _userManager = userManager;
    }

    public async Task<List<Product>> GetProductsForUserAsync(long userId)
    {
        var user = await _userManager.GetUserByIdAsync(userId);
        var organizationUnits = await _userManager.GetOrganizationUnitsAsync(user);
        var organizationUnitIds = organizationUnits.Select(ou => ou.Id);

        return await _productRepository.GetAllListAsync(p => organizationUnitIds.Contains(p.OrganizationUnitId));
    }
}

We simply found Ids of OUs of the user. Then used Contains condition while getting products. Surely, we could create a LINQ query with join to get the same list.

We may want to get products in user's OUs including their child OUs:

public class ProductManager : IDomainService
{
    private readonly IRepository<Product> _productRepository;
    private readonly IRepository<OrganizationUnit, long> _organizationUnitRepository;
    private readonly UserManager _userManager;

    public ProductManager(
        IRepository<Product> productRepository, 
        IRepository<OrganizationUnit, long> organizationUnitRepository, 
        UserManager userManager)
    {
        _productRepository = productRepository;
        _organizationUnitRepository = organizationUnitRepository;
        _userManager = userManager;
    }

    [UnitOfWork]
    public virtual async Task<List<Product>> GetProductsForUserIncludingChildOusAsync(long userId)
    {
        var user = await _userManager.GetUserByIdAsync(userId);
        var organizationUnits = await _userManager.GetOrganizationUnitsAsync(user);
        var organizationUnitCodes = organizationUnits.Select(ou => ou.Code);

        var query =
            from product in _productRepository.GetAll()
            join organizationUnit in _organizationUnitRepository.GetAll() on product.OrganizationUnitId equals organizationUnit.Id
            where organizationUnitCodes.Any(code => organizationUnit.Code.StartsWith(code))
            select product;

        return query.ToList();
    }
}

We combined Any with StartsWith condition in a LINQ join statement.

Surely, there may be much more complex requirements, but all can be done with LINQ or SQL.

Settings

You can inject and use IOrganizationUnitSettings interface to get Organization Units setting values. Currently, there is just a single setting that can be changed for your application needs:

• MaxUserMembershipCount: Maximum allowed membership count for a user.
  Default value is int.MaxValue which allows a user to be member of unlimited OUs in same time.
  Setting name is a constant defined in AbpZeroSettingNames.OrganizationUnits.MaxUserMembershipCount.

You can change setting values using setting manager.