ASP.NET DbContext setup

Will look somethng like

appsettings.json

"ConnectionStrings": {
    "DefaultConnection": "Server=(localdb)\\mssqllocaldb;Database=aspnet-database;Trusted_Connection=True;MultipleActiveResultSets=true",
    "BlogsConnection":  "Server=(localdb)\\mssqllocaldb;Database=BlogsDb"
},
"Logging": {
    "IncludeScopes": false,
    "LogLevel": {
        "Default": "Warning"
    }
}

BlogsDbContext.json

public class BlogsDbContext : DbContext
{
    public DbSet Blogs { get; set; }
    public DbSet Posts { get; set; }

    public BlogsDbContext(DbContextOptions options)
        : base(options)
    {
    }
}

Startup.json

public void ConfigureServices(IServiceCollection services)
{
    // Add framework services.
    services.AddDbContext(options =>
         options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));
    services.AddIdentity<ApplicationUser, IdentityRole>()
        .AddEntityFrameworkStores()
        .AddDefaultTokenProviders();
    services.AddEntityFramework()
        .AddDbContext(options =>
          options.UseSqlServer(Configuration.GetConnectionString("BlogsConnection")));

    services.AddMvc();
    services.AddAuthorization(options =>
    {
        options.AddPolicy("RequireAdminRole", policy => policy.RequireRole("Admin"));
    });
    // Add application services.
    services.AddTransient<IEmailSender, AuthMessageSender>();
    services.AddTransient<ISmsSender, AuthMessageSender>();

AdminController.json

"ConnectionStrings": {
    "DefaultConnection": "Server=(localdb)\\mssqllocaldb;Database=aspnet-database;Trusted_Connection=True;MultipleActiveResultSets=true",
    "BlogsConnection":  "Server=(localdb)\\mssqllocaldb;Database=BlogsDb"
},
"Logging": {
    "IncludeScopes": false,
    "LogLevel": {
        "Default": "Warning"
    }
}
Some Debugging usefull steps
Steps for adding more DbContexts to an application:

  1. Create a DbContext Class
  2. Create a Connection string DbContext in appsettings.json
  3. Add the DbContext to configured services in Startup.cs
  4. Setup the DbContext in the controllers that will query it.
  5. Open the package manager and run the 2 lines below. (if “-Context” doesn’t work try “–context”
  6. Run your program and let EntityFrameworkCore take care of the rest.

On Windows ( In Package Management Console you can run )

Add-Migration InitialCreate -Context MyContext
Update-Database -Context MyContex

On Linux ( VScode )

dotnet ef migrations add InitialCreate // TimeStamp_InitialCreate.Designer.cs
OR dotnet ef migrations add InitialCreate --context MyContext
dotnet ef database update
OR dotnet ef database update --context MyContext

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