EntityFrameworkCore.Seed

This project is not an official entity framework core library. It aims to give the ability to seed values inside the database for testing/integration purpose.

Getting Started

Prerequisites

You need to have a configured Entity Framework Core 2.+ project.

Installing

Install the packages

To make things work, you need to install two packages first.

The first one :

Package-Install Authfix.EntityFrameworkCore.Seed

This is the base package. It will allow you to run the seed method inside your app. It contains the base classes/main mechanisms.

The second one depends of your database provider. Actually we have only two providers : InMemory and Postgresql

You can install

Package-Install Authfix.EntityFrameworkCore.InMemory

or

Package-Install Authfix.EntityFrameworkCore.Postgresql

Update your program.cs

After packages installation process, you can update your program.cs to run the seed method.

public static void Main(string[] args)
{
    var webHost = BuildWebHost(args);

    // Do not forget to migrate database if needed before seeding.
    webHost.SeedData<ApplicationDbContext>();

    webHost.Run();
}

This method will check if you have pending seeds and run it if necessary.

Update your Startup.cs

services
    .AddEntityFrameworkNpgsql()
    .AddDbContext<ApplicationDbContext>(options =>
    {
        options.UseNpgsql(Configuration.GetConnectionString("DefaultConnection"));
        options.UseNpgsqlSeed(Assembly.GetEntryAssembly().FullName);
    });

You must add function of your provider, the corresponding Use method and the assembly where your seed classes are stored.

Add your first seed

To create a seed, it's actually manually, the CLI like Entity Framework Core is not ready yet.

So you need to create a class and add an inheritance and a custom attribute like EF Migration.

[SeedAttribute("20171010165344_InitialScenario")]
public class Seed_20171010165344_InitialScenario : SeederBase
{
    protected override void UpdateEntities()
    {
        var users = GetDbSet<User>();

        for (int i = 1; i < 50; i++)
        {
            var newUser = new User
            {
                Id = i
            };

            users.Add(newUser);
        }
    }
}

The SeedAttribute take a name like {year}{month}{day}{hour}{minutes}{seconds}_{name}.

You need to inherit the class with SeederBase and you just have to fill the UpdateEntities method.

The name of the class is not important

Running the tests

To run the tests, you just have to launch Visual Studio ;)

Built With

• Dotnet Core - The base framework used
• Entiy Framework - The ORM

Contributing

Please read CONTRIBUTING.md for details on our code of conduct, and the process for submitting pull requests to us.

Versioning

We use SemVer for versioning. For the versions available, see the tags on this repository.

Authors

• Thomas Bailly - Initial work - Authfix

See also the list of contributors who participated in this project.

License

This project is licensed under the MIT License - see the LICENSE.md file for details

Acknowledgments

• My work is based on the migration mechanism created by the entity framework team.