SSW Vertical Slice Architecture Template
- π€ What is it?
- β¨ Features
- π Getting Started
- π Learn More
- π Publishing Template
- π€ Contributing
An enterprise ready solution template for Vertical Slice Architecture. This template is just one way to apply the Vertical Slice Architecture.
Read more on SSW Rules to Better Vertical Slice Architecture
- 
π¨ dotnet newcli template - to get you started quickly
- 
π Aspire - Dashboard
- Resource orchestration
- Observability
- Simple dev setup - automatic provisioning of database server, schema, and data
 
- 
π― Domain Driven Design Patterns - AggregateRoot
- Entity
- ValueObject
- DomainEvent
 
- 
β‘ FastEndpoints - developer friendly alternative to Minimal APIs. - Strongly-typed requests and responses
- Automatic validation with FluentValidation
- Support for commands and events
 
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π OpenAPI/Swagger - easily document your API 
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π Global Exception Handling - it's important to handle exceptions in a consistent way & protect sensitive information - Transforms exceptions into a consistent format following the RFC7231 memo
 
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ποΈ Entity Framework Core - for data access - Comes with Migrations & Data Seeding
- as per ssw.com.au/rules/rules-to-better-entity-framework/
 
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π§© Specification Pattern - abstract EF Core away from your business logic 
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π REPR (Request-Endpoint-Response) Pattern - for structured endpoints 
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π¦ ErrorOr - fluent result pattern (instead of exceptions) 
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π¦ FluentValidation - for validating requests 
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π Strongly Typed IDs - to combat primitive obsession - e.g. pass CustomerIdtype into methods instead ofint, orGuid
- Entity Framework can automatically convert the int, Guid, nvarchar(..) to strongly typed ID.
 
- e.g. pass 
- 
π Directory.Build.Props - Consistent build configuration across all projects in the solution
- e.g. Treating Warnings as Errors for Release builds
 
- Custom per project
- e.g. for all test projects we can ensure that the exact same versions of common packages are referenced
- e.g. XUnit and NSubstitute packages for all test projects
 
 
- Consistent build configuration across all projects in the solution
- 
βοΈ EditorConfig - comes with the SSW.EditorConfig - Maintain consistent coding styles for individual developers or teams of developers working on the same project using different IDEs
- as per ssw.com.au/rules/consistent-code-style/
 
- 
π§ͺ Testing - as per ssw.com.au/rules/rules-to-better-testing/
- Simpler Unit Tests for Application
- No Entity Framework mocking required thanks to Specifications
- as per ssw.com.au/rules/rules-to-better-unit-tests/
 
- Better Integration Tests
- Using Respawn and TestContainers
- Integration Tests at Unit Test speed
- Test Commands and Queries against a Real database
- No Entity Framework mocking required
- No need for In-memory database provider
 
 
- 
Architecture Tests - Using NetArchTest
- Know that the team is following the same Vertical Slice Architecture fundamentals
- The tests are automated so discovering the defects is fast
 
- Install the SSW VSA template
dotnet new install SSW.VerticalSliceArchitecture.Template 
[!NOTE] The template only needs to be installed once. Running this command again will update your version of the template.
- 
Create a new directory mkdir Sprout cd Sprout
- 
Create a new solution dotnet new ssw-vsa 
[!NOTE]
nameis optional; if you don't specify it, the directory name will be used as the solution name and project namespaces.
Alternatively, you can specify the name and output directory as follows:
dotnet new ssw-vsa --name {{SolutionName}}- 
Change directory 
 Windows:cd tools\AppHost\ Mac/Linux: cd tools/AppHost/
- 
Run the solution dotnet run 
[!NOTE] The first time you run the solution, it may take a while to download the docker images, create the DB, and seed the data.
- Open https://localhost:7255/swagger in your browser to see it running οΈπββοΈ
To speed up development there is a dotnet new template to create a full Vertical Slice:
- Creates a domain object in Common/Domain/*
- Adds domain configuration in Common/Persistence/*
- Creates Command & Query API endpoints in Features/*
- Add a new Feature
cd src/WebApi/ dotnet new ssw-vsa-slice --feature Person --feature-plural People
--feature or -f where the value is the singular name of the feature.
--feature-plural or -fp where the value is the plural name of the feature.
- 
Configure this Feature This project uses strongly typed IDs, which require registration in the VogenEfCoreConvertersclass:// Register the newly created Entity ID here [EfCoreConverter<PersonId>] internal sealed partial class VogenEfCoreConverters; 
- 
Add a migration for the new Entity dotnet ef migrations add --project src/WebApi/WebApi.csproj --startup-project src/WebApi/WebApi.csproj --output-dir Common/Database/Migrations PersonTable 
Due to .NET Aspire orchestrating the application startup and migration runner, EF migrations need to be handled a little differently to normal.
Adding new migrations is still the same old command you would expect, but with a couple of specific parameters to account for the separation of concerns. This can be performed via native dotnet tooling or through the Aspire CLI:
- Run either of following commands from the root of the solution.
dotnet ef migrations add YourMigrationName --project ./src/Infrastructure/Infrastructure.csproj --startup-project ./src/WebApi/WebApi.csproj --output-dir ./Persistence/Migrationsaspire exec --resource api -- dotnet ef migrations add YourMigrationName --project ../Infrastructure/Infrastructure.csproj --output-dir ./Persistence/Migrations.NET Aspire handles this for you - just start the project!
This is where things need to be done a little differently and requires the Aspire CLI.
- Enable the execfunction:
aspire config set features.execCommandEnabled true- Pass the EF migration shell command through Aspire from the root of the solution:
aspire exec --resource api -- dotnet ef migrations remove --project ..\Infrastructure --forceNote
The --force flag is needed because .NET Aspire will start the application when this command is run, which triggers the migrations to run. This will apply your migrations to the database, and make EF Core unhappy when it tries to delete the latest migration. This should therefore be used with caution - a safer approach is to "roll forward" and create new migrations that safely undo the undesired change(s).
The template can be deployed to Azure via the Azure Developer CLI (AZD). This will setup the following:
- Azure App Services: API + MigrationService
- Azure SQL Server + Database: Data storage
- Application Insights + Log Analytics: For monitoring and logging
- Managed Identities: For secure access to Azure resources
- Azure Container Registry: For storing Docker images
- 
Authenticate with Azure azd auth login 
- 
Initialize AZD for the project azd init 
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Update environment variables azd env set ASPNETCORE_ENVIRONMENT Development
- 
Deploy to Azure azd up 
Note
azd up combines azd provision and azd deploy commands to create the resources and deploy the application. If running this from a CI/CD
pipeline, you can use azd provision and azd deploy separately in the appropriate places.
graph TD;
    subgraph ASP.NET Core Web App
        subgraph Slices
            A[Feature A]
            B[Feature B]
        end
        Slices --> |depends on| Common
        Host --> |depends on| Common
        Host --> |depends on| Slices
        ASPNETCore[ASP.NET Core] --> |uses| Host
    end
    Common[Common]
    Template will be published to NuGet.org when changes are made to VerticalSliceArchitecture.nuspec on the main branch.
- Update the versionattribute inVerticalSliceArchitecture.nuspec
- Merge your PR
- packageGitHub Action will run and publish the new version to NuGet.org
- Create a GitHub release to document the changes
[!NOTE] We are now using CalVer for versioning. The version number should be in the format
YYYY.M.D(e.g.2024.2.12).
Contributions, issues and feature requests are welcome! See Contributing for more information.

