EntityFrameworkSandbox.Template 1.0.1

Entity Framework Sandbox

The Entity Framework Sandbox is a CLI project template that allows you to quickly spin up a functioning project running on the latest version of EF with a real database and real data.

This can be useful in the following scenario:

• Exploring new features of EF such as
• Safely exploring changes to a real application
• Replicating EF issues in an isolated environment

This is not intended to be a starting point for a production application.

Prerequisites

• VS2022
• .NET 7
• LocalDB

Setup

Template Installation

Install the dotnet CLI template via:

dotnet new --install EntityFrameworkSandbox.Template 

Project Creation

You can use the template to create a new project via:

mkdir my-ef-sandbox
cd my-ef-sandbox
dotnet new ef-sandbox --name EF.Sandbox --output .\

Alternatively, you can create the project directly into a new sub-folder via:

dotnet new ef-sandbox --name EF.Sandbox

Usage

Initializing the Database

dotnet run init

Running Commands

dotnet run get-posts
dotnet run get-blogs

Showing Help

Run the following from your bin directory:

.\{Your.Project}.exe --help

For example:

Customization

Writing Commands & Queries

New commands can be added to /Cli/Commands/.

For example:

public class GetBlogsCommand : AsyncCommand
{
    private readonly BloggingContext _db;
    private readonly ILogger<GetBlogsCommand> _logger;

    public GetBlogsCommand(BloggingContext context, ILogger<GetBlogsCommand> logger)
    {
        _db = context;
        _logger = logger;
    }

    public override async Task<int> ExecuteAsync(CommandContext context)
    {
        _logger.LogInformation("Getting Blogs...");

        var blogs = await _db.Blogs.ToListAsync();

        foreach (var blog in blogs)
            _logger.LogInformation(blog.ToString());

        return 0;
    }
}

Overriding Model Configuration

This can be done in the configuration classes:

internal class PostConfiguration : IEntityTypeConfiguration<Post>
{
    public void Configure(EntityTypeBuilder<Post> builder)
    {
        // NOTE: Custom model configuration goes here
    }
}

Overriding the Connection String

Leave appsettings.json as is and add a secret via the CLI. This ensures your connection does not get checked into source control

dotnet user-secrets init
dotnet user-secrets set "ConnectionStrings:Default" "{Your Connection String}"

Schema Changes

The project is designed to use migrations for schema upgrades. However, if you prefer to instead drop and create the DB every time you can set Application.EnableMigrations to false in appsettings.json:

"Application": {
    "EnableMigrations": false
}

Troubleshooting

• Ensure the connection matches if you are using something other than local DB

Deployment

Updated Nuget Version

A new package will be pushed to Nuget anytime EntityFrameworkSandbox.Template.nuspec is changed on main branch. Normally this will happen via a package version change.

Version needs to be updated in:

• EntityFrameworkSandbox.Template.nuspec
• EntityFrameworkSandbox.Template.csproj