EntityFrameworkCore.Scaffolding.Handlebars 3.0.0-preview8

This is a prerelease version of EntityFrameworkCore.Scaffolding.Handlebars.
There is a newer version of this package available.
See the version list below for details.
dotnet add package EntityFrameworkCore.Scaffolding.Handlebars --version 3.0.0-preview8
NuGet\Install-Package EntityFrameworkCore.Scaffolding.Handlebars -Version 3.0.0-preview8
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="EntityFrameworkCore.Scaffolding.Handlebars" Version="3.0.0-preview8" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add EntityFrameworkCore.Scaffolding.Handlebars --version 3.0.0-preview8
#r "nuget: EntityFrameworkCore.Scaffolding.Handlebars, 3.0.0-preview8"
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.
// Install EntityFrameworkCore.Scaffolding.Handlebars as a Cake Addin
#addin nuget:?package=EntityFrameworkCore.Scaffolding.Handlebars&version=3.0.0-preview8&prerelease

// Install EntityFrameworkCore.Scaffolding.Handlebars as a Cake Tool
#tool nuget:?package=EntityFrameworkCore.Scaffolding.Handlebars&version=3.0.0-preview8&prerelease

Entity Framework Core Scaffolding with Handlebars

Scaffold EF Core models using Handlebars templates.

Prerequisites

Database Setup

  1. Use SQL Server Management Studio to connect to SQL Server
    • The easiest is to use LocalDb, which is installed with Visual Studio.
      Connect to: (localdb)\MsSqlLocalDb.
    • Create a new database named NorthwindSlim.
    • Download the data file from http://bit.ly/northwindslim.
    • Unzip NorthwindSlim.sql and run the script to create tables and populate them with data.

Usage

  1. Create a new .NET Core class library.

    • If necessary, edit the csproj file to update the TargetFramework to 3.0.

    Note: Using the EF Core toolchain with a .NET Standard class library is currently not supported. Instead, you can add a .NET Standard class library to the same solution as the .NET Core library, then add existing items and select Add As Link to include entity classes.

  2. Add EF Core SQL Server and Tools NuGet packages.

    • Microsoft.EntityFrameworkCore.SqlServer
    • Microsoft.EntityFrameworkCore.Design
  3. Add the EntityFrameworkCore.Scaffolding.Handlebars NuGet package:

    • EntityFrameworkCore.Scaffolding.Handlebars
  4. Remove Class1.cs and add a ScaffoldingDesignTimeServices class.

    • Implement IDesignTimeServices by adding a ConfigureDesignTimeServices method that calls services.AddHandlebarsScaffolding.
    • You can optionally pass a ReverseEngineerOptions enum to indicate if you wish to generate only entity types, only a DbContext class, or both (which is the default).
    public class ScaffoldingDesignTimeServices : IDesignTimeServices
    {
        public void ConfigureDesignTimeServices(IServiceCollection services)
        {
            var options = ReverseEngineerOptions.DbContextAndEntities;
            services.AddHandlebarsScaffolding(options);
        }
    }
    
  5. Open a command prompt at the project level and use the EF .NET Core CLI tools to reverse engineer a context and models from an existing database.

    • Get help on dotnet-ef-dbcontext-scaffold at the command line: dotnet ef dbcontext scaffold -h
    • Execute the following command to reverse engineer classes from the NorthwindSlim database:
    dotnet ef dbcontext scaffold "Data Source=(localdb)\MSSQLLocalDB; Initial Catalog=NorthwindSlim; Integrated Security=True" Microsoft.EntityFrameworkCore.SqlServer -o Models -c NorthwindSlimContext -f --context-dir Contexts
    
    • You should see context and/or entity classes appear in the Models folder of the project.
    • You will also see a CodeTemplates folder appear containing Handlebars templates for customizing generation of context and entity type classes.
    • Add -d to the command to use data annotations. You will need to add the System.ComponentModel.Annotations package to a .NET Standard library containing linked entity classes.
  6. You may edit any of the template files which appear under the CodeTemplates folder.

    • For now you can just add some comments, but you may wish to customize the templates in other ways, for example, by inheriting entities from a base class or implementing specific interfaces.
    • When you run the dotnet-ef-dbcontext-scaffold command again, you will see your updated reflected in the generated classes.

Handlebars Helpers and Transformers

You can register Handlebars helpers in the ScaffoldingDesignTimeServices where setup takes place.

  • Create a named tuple as shown with myHelper below.
  • The context parameter of the helper method provides model data injected by the Handlebars scaffolding extension.
  • Pass the tuple to the AddHandlebarsHelpers extension method.
  • To use Handlebars helper defined above, add the following to any of the .hbs files within the CodeTemplates folder: {{my-helper}}
  • You may register as many helpers as you wish.

You can pass transform functions to AddHandlebarsTransformers in order to customize generation of entity type definitions, including class names, constructors and properties.

public class ScaffoldingDesignTimeServices : IDesignTimeServices
{
    public void ConfigureDesignTimeServices(IServiceCollection services)
    {
        // Generate both context and entities
        var options = ReverseEngineerOptions.DbContextAndEntities;

        // Register Handlebars helper
        var myHelper = (helperName: "my-helper", helperFunction: (Action<TextWriter, Dictionary<string, object>, object[]>) MyHbsHelper);

        // Add Handlebars scaffolding templates
        services.AddHandlebarsScaffolding(options);

        // Add optional Handlebars helpers
        services.AddHandlebarsHelpers(myHelper);

        // Add Handlebars transformer for Country property
        services.AddHandlebarsTransformers(
            propertyTransformer: e =>
                e.PropertyName == "Country"
                    ? new EntityPropertyInfo("Country", e.PropertyName)
                    : new EntityPropertyInfo(e.PropertyType, e.PropertyName));

        // Add optional Handlebars transformers
        //services.AddHandlebarsTransformers(
        //    entityNameTransformer: n => n + "Foo",
        //    entityFileNameTransformer: n => n + "Foo",
        //    constructorTransformer: e => new EntityPropertyInfo(e.PropertyType + "Foo", e.PropertyName + "Foo"),
        //    propertyTransformer: e => new EntityPropertyInfo(e.PropertyType, e.PropertyName + "Foo"),
        //    navPropertyTransformer: e => new EntityPropertyInfo(e.PropertyType + "Foo", e.PropertyName + "Foo"));
    }

    // Sample Handlebars helper
    void MyHbsHelper(TextWriter writer, Dictionary<string, object> context, object[] parameters)
    {
        writer.Write("// My Handlebars Helper");
    }
}

Extending the OnModelCreating Method

There are times when you might like to modify generated code, for example, by adding a HasConversion method to an entity property in the OnModelCreating method of the generated class that extends DbContext. However, doing so may prove futile because added code would be overwritten the next time you run the dotnet ef dbcontext scaffold command.

  • Rather than modifying generated code, a better idea would be to extend it by using partial classes and methods. To enable this scenario, the generated DbContext class is already defined using the partial keyword, and it contains a partial OnModelCreatingPartial method that is invoked at the end of the OnModelCreating method.

  • To implement the partial method, simply add a new class to your project with the same name as the generated DbContext class, and define it as partial. Then add a OnModelCreatingPartial method with the same signature as the partial method defined in the generated DbContext class.

  • Install the global dotnet ef tool.

dotnet tool install --global dotnet-ef --version 3.0.0-*
  • Open a command prompt at the project root and execute:
dotnet ef dbcontext scaffold "Data Source=(localdb)\MSSQLLocalDB; Initial Catalog=NorthwindSlim; Integrated Security=True" Microsoft.EntityFrameworkCore.SqlServer -o Models -c NorthwindSlimContext -f --context-dir Contexts
Product Compatible and additional computed target framework versions.
.NET net5.0 was computed.  net5.0-windows was computed.  net6.0 was computed.  net6.0-android was computed.  net6.0-ios was computed.  net6.0-maccatalyst was computed.  net6.0-macos was computed.  net6.0-tvos was computed.  net6.0-windows was computed.  net7.0 was computed.  net7.0-android was computed.  net7.0-ios was computed.  net7.0-maccatalyst was computed.  net7.0-macos was computed.  net7.0-tvos was computed.  net7.0-windows was computed.  net8.0 was computed.  net8.0-android was computed.  net8.0-browser was computed.  net8.0-ios was computed.  net8.0-maccatalyst was computed.  net8.0-macos was computed.  net8.0-tvos was computed.  net8.0-windows was computed. 
.NET Core netcoreapp3.0 was computed.  netcoreapp3.1 was computed. 
.NET Standard netstandard2.1 is compatible. 
MonoAndroid monoandroid was computed. 
MonoMac monomac was computed. 
MonoTouch monotouch was computed. 
Tizen tizen60 was computed. 
Xamarin.iOS xamarinios was computed. 
Xamarin.Mac xamarinmac was computed. 
Xamarin.TVOS xamarintvos was computed. 
Xamarin.WatchOS xamarinwatchos was computed. 
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Learn more about Target Frameworks and .NET Standard.

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ErikEJ/EFCorePowerTools
Entity Framework Core Power Tools - reverse engineering, migrations and model visualization in Visual Studio & CLI
Version Downloads Last updated
8.0.0 4,632 1/27/2024
8.0.0-beta2 473 12/30/2023
8.0.0-beta1 1,442 11/23/2023
7.0.0 51,238 6/12/2023
7.0.0-beta1 18,569 11/20/2022
6.0.3 347,297 1/22/2022
6.0.2 9,515 12/23/2021
6.0.1 1,400 12/21/2021
6.0.0 4,788 12/15/2021
6.0.0-preview5 183 12/15/2021
6.0.0-preview4 259 12/5/2021
6.0.0-preview3 4,081 11/30/2021
6.0.0-preview2 3,579 11/25/2021
6.0.0-preview1 3,366 11/25/2021
5.0.5-preview1 5,485 9/25/2021
5.0.4 66,606 9/23/2021
5.0.3 12,153 9/15/2021
5.0.2 83,390 2/19/2021
5.0.1 20,846 12/5/2020
5.0.0 2,274 11/15/2020
5.0.0-rc.2 699 10/18/2020
3.8.5 27,443 11/7/2020
3.8.4 14,889 9/28/2020
3.8.3 94,864 8/18/2020
3.8.2 3,518 7/21/2020
3.8.1 7,825 7/8/2020
3.7.0 42,834 5/1/2020
3.6.0 20,164 1/6/2020
3.5.1 2,263 12/15/2019
3.5.0 6,072 10/18/2019
3.0.0 1,180 10/14/2019
3.0.0-preview8 453 8/26/2019
2.1.1 34,638 8/5/2019
2.1.0 1,352 7/19/2019
2.0.0 5,551 6/25/2019
1.7.2 99,423 1/6/2019
1.7.1 960 1/5/2019
1.7.0 734 1/3/2019
1.6.0 1,367 12/17/2018
1.5.1 23,500 7/7/2018
1.5.0 1,216 6/22/2018
1.4.1 1,152 7/7/2018
1.4.0 1,020 6/23/2018
1.1.1 1,067 6/19/2018
1.1.0 1,153 6/3/2018
1.0.0 1,091 5/30/2018
1.0.0-rc3 1,062 5/26/2018
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1.0.0-beta 2,530 10/25/2017