EntityFramework Core: Generate Migration Scripts in a Separate Project

In entity-framework code-first solution, we usually generate migrations scripts in the default startup project. For instance, for ASP.NET Core applications, the scripts can be generated in Migrations folder of the web application project. This articles shows an approach to generate migration scripts in a separate project.

Scenario

Assuming the following solution setup:

sln
      WebProject
      DataModels
      Migrations

In solution folder sln, there are three projects: 

• WebProject: ASP.NET Core web application project.
• DataModels: all the entity framework models and application DbContext classes are defined here.
• Migrations: all the migration scripts.

The task is to generate migration scripts in Migrations project folder. 

Resolution

The following steps provide one solution to implement the above task.

1. Open Command Prompt (Windows) or Terminal (Linux).
2. Change current folder to sln:
   

   cd sln

3. Add initial migration script:
   

   dotnet ef migrations add InitMigrations --startup-project WebProject

   The above command will generate initial migration scripts by default in WebProject. The startup project is set as WebProject. 

4. Create Migrations project as a C# library project with all the necessary references to entity framework package and DataModels project.
5. Move the generated scripts to project Migrations manually.
6. Generate new migrations using the following command ongoing forward:
   

   dotnet ef migrations add MyNewMigration --startup-project WebProject --project Migrations

References

Using a Separate Migrations Project - EF Core | Microsoft Docs