abp/docs/en/Startup-Templates/Application-Single-Layer.md

Application (Single Layer) Startup Template

Introduction

This template provides a single-layered application for a quick start with ABP Framework.

This document explains the solution structure and project in detail.

What is the Difference Between the Application Startup Templates?

ABP's Application Startup Template provides a well-organized and layered solution to create maintainable business applications based on the Domain Driven Design (DDD) practices. However, some developers find this template a little bit complex (or unnecessary) for simple and short-time applications.

At this point, a single-layer application template has been created for such applications. This template has the same functionality, features and modules on runtime with the Application Startup Template but the development model is minimal and everything is in a single project (.csproj).

How to Start with It?

You can use the ABP CLI to create a new project using this startup template. Alternatively, you can directly create & download this startup template from the Get Started page. How to download via CLI is explained in this section.

Firstly, install the ABP CLI if you haven't installed it before:

dotnet tool install -g Volo.Abp.Cli

Then, use the abp new command in an empty folder to create a new solution:

abp new Acme.BookStore -t app-nolayers

• Acme.BookStore is the solution name, like YourCompany.YourProduct. You can use single-level, two-level or three-level naming.
• In this example, the -t option (or --template option) specifies the template name.

Specify the UI Framework

This template provides multiple UI frameworks:

• mvc: ASP.NET Core MVC UI with Razor Pages (default)
• blazor-server: Blazor Server UI
• angular: Angular UI
• none: Without UI

Currently, this template doesn't have Blazor WASM UI, because it requires 3 projects at least (server-side, UI and shared library between these two projects).

Use the -u or --ui option to specify the UI framework while creating the solution:

abp new Acme.BookStore -t app-nolayers -u angular

• This example specifies the UI type (-u option) as angular, you can also specify mvc or blazor-server for UI type.

Specify the Database Provider

This template supports the following database providers:

• ef: Entity Framework Core (default)
• mongodb: MongoDB

Use the -d (or --database-provider) option to specify the database provider while creating the solution:

abp new Acme.BookStore -t app-nolayers -d mongodb

Solution Structure

If you don't specify any additional options while creating an app-nolayers template, you will have a solution as shown below:

It's a single-layer template rather than a layered-architecture solution (like the Application Startup Template). It's helpful to create a running application quickly without considering the layered architecture.

Folder Structure

Since this template provides a single-layer solution, we've separated concerns into folders instead of layers and you can see the pre-defined folders as shown below:

• You can define your entities, application services, DTOs, etc. in this single project (in the related folders).
• For example, you can define your application services and DTOs under the Services folder.

How to Run?

Before running the application, you need to create the database and seed the initial data. To do that, you can run the following command in the directory of your project:

dotnet run --migrate-database

• This command will create the database and seed the initial data for you. Then you can run the application with any IDE that supports .NET or by running the dotnet run CLI command in the directory of your project. The default username is admin and the password is 1q2w3E*.

While creating a database & applying migrations seem only necessary for relational databases, this project comes even if you choose a NoSQL database provider (like MongoDB). In that case, it still seeds the initial data which is necessary for the application.

Angular UI

If you choose Angular as the UI framework, the solution will be separated into two folders:

• An angular folder that contains the Angular UI application, the client-side code.
• An aspnet-core folder that contains the ASP.NET Core solution (a single project), the server-side code.

The server-side is similar to the solution described in the Solution Structure section above. This project serves the API, so the Angular application can consume it.

The client-side application consumes the HTTP APIs as mentioned. You can see the folder structure of the Angular project shown below: