SaaS module

This module implements the User and Role system of an application;

  • Manage tenants and editions in the system. A tenant is allowed to have one edition.
  • Set features of tenants.
  • Set connection string of tenants.
  • Set features of editions.

See the module description page for an overview of the module features.

How to install

Identity is pre-installed in the startup templates. So, no need to manually install it.


This module follows the module development best practices guide and consists of several NuGet and NPM packages. See the guide if you want to understand the packages and relations between them.

NuGet packages

  • Volo.Saas.Domain.Shared
  • Volo.Saas.Domain
  • Volo.Saas.EntityFrameworkCore
  • Volo.Saas.MongoDB
  • Volo.Saas.Tenant.Application
  • Volo.Saas.Tenant.Application.Contracts
  • Volo.Saas.Tenant.HttpApi
  • Volo.Saas.Tenant.HttpApi.Client
  • Volo.Saas.Tenant.Web
  • Volo.Saas.Host.Application
  • Volo.Saas.Host.Application.Contracts
  • Volo.Saas.Host.HttpApi
  • Volo.Saas.Host.HttpApi.Client
  • Volo.Saas.Host.Web

NPM packages

  • @volo/
  • @volo/

User interface

Menu items

SaaS module adds the following items to the "Main" menu, under the "Administration" menu item:

  • Tenants: Tenant management page.
  • Editions: Edition management page.

SaasHostMenuNames and SaasTenantMenuNames classes have the constants for the menu item names.


Tenant management

Tenant page is used to manage tenants in the system.


You can create a new tenant or edit a tenant in this page:


Connection String

You can manage connection string of a tenant in case you want to use a separate database for a specific tenant. If you want to use Host database for a tenant, select "Use the Shared Database" option.


Tenant Features

You can set features of tenants.


Edition management

Editions page is used to manage the editions in your system.


You can create a new edition or edit an existing edition in this page:


Edition Features

You can set features of an edition in this page:


Data seed

This module adds some initial data (see the data seed system) to the database when you run the .DbMigrator application:

  • Creates an Standard edition.


Domain layer


This module follows the Entity Best Practices & Conventions guide.


A tenant is generally represents a group of users who share a common access with specific privileges to the software instance.

  • Tenant (aggregate root): Represents a tenant in the system.
    • TenantConnectionString (collection): Connection strings of a tenant.

An edition is typically a category of features of the application.

  • Edition (aggregate root): Represents an edition in the system.


This module follows the Repository Best Practices & Conventions guide.

Following custom repositories are defined for this module:

  • ITenantRepository
  • IEditionRepository

Domain services

This module follows the Domain Services Best Practices & Conventions guide.

Tenant manager

TenantManager is used to create tenants, change and validate name of tenants.

Application layer

Application services

  • TenantAppService (implements ITenantAppService): Implements the use cases of the tenant management UI.
  • EditionAppService (implement IEditionAppService): Implements the use cases of the edition management UI.

Database providers


Table / collection prefix & schema

All tables/collections use the Saas prefix by default. Set static properties on the SaasDbProperties class if you need to change the table prefix or set a schema name (if supported by your database provider).

Connection string

This module uses Saas for the connection string name. If you don't define a connection string with this name, it fallbacks to the Default connection string.

See the connection strings documentation for details.

Entity Framework Core

  • SaasTenants
    • SaasTenantConnectionStrings
  • SaasEditions


  • SaasTenants
  • SaasEditions


See the SaasHostPermissions class members for all permissions defined for this module.

Distributed Events

This module doesn't define any additional distributed event. See the standard distributed events.

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