System.InvalidOperationException: “No database provider has been configured for this DbContext”

[ajitgoel]

Adding migrations and updating database were working fine but seem to have hit a snag after updating to the latest version of Entity Framework core. What am I missing?

Failing Command
add-migration authenticationtoken -Context ApplicationDbContext -verbose

ApplicationDbContext.cs

public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
{
    // I added this constructor after add-migration complained about needing a parameterless constructor.     
    public ApplicationDbContext()
    {
    }

    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }
   ...................
}

Startup.cs

public void ConfigureServices(IServiceCollection services)
{
      services.AddDbContext<ApplicationDbContext>(options=> options.UseSqlServer(Configuration.GetConnectionString("SQLServerConnectionString")));
..............
}

Program.cs

public class Program
{
    public static void Main(string[] args)
    {
      var path = Directory.GetCurrentDirectory();
      var environmentName =Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT") ?? "Production";
      var configuration = new ConfigurationBuilder()
      .SetBasePath(path)
      .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
      .AddJsonFile($"appsettings.{environmentName}.json", optional: false, reloadOnChange: true)
      .Build();
      Log.Logger = new LoggerConfiguration()
        .Enrich.FromLogContext()
        .ReadFrom.Configuration(configuration)
        .CreateLogger();
      try
      {
        WebHost.CreateDefaultBuilder(args)
          .UseStartup<Startup>()
          .UseSerilog()
          .Build()
          .Run();
      }
      finally
      {
        Log.CloseAndFlush();
      }
    }
  }

project.csproj:

<Project Sdk="Microsoft.NET.Sdk.Web">
  <PropertyGroup>
    <TargetFramework>netcoreapp2.2</TargetFramework>
    <LangVersion>default</LangVersion>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Braintree" Version="4.11.0" />
    <PackageReference Include="BuildBundlerMinifier" Version="2.9.406" />
    <PackageReference Include="Hangfire" Version="1.7.3" />
    <PackageReference Include="Microsoft.AspNetCore.App" />
    <PackageReference Include="Microsoft.AspNetCore.Razor.Design" Version="2.2.0" PrivateAssets="All" />
    <PackageReference Include="Microsoft.Azure.Cosmos.Table" Version="1.0.1" />
    <PackageReference Include="Microsoft.Azure.Storage.Blob" Version="10.0.3" />
    <PackageReference Include="Microsoft.Azure.Storage.Common" Version="10.0.3" />
    <PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="2.2.3" />
    <PackageReference Include="morelinq" Version="3.1.1" />
    <PackageReference Include="Newtonsoft.Json" Version="12.0.2" />
    <PackageReference Include="Sendgrid" Version="9.11.0" />
    <PackageReference Include="Serilog.AspNetCore" Version="2.1.1" />
    <PackageReference Include="Serilog.Extensions.Logging" Version="2.0.4" />
    <PackageReference Include="Serilog.Settings.AppSettings" Version="2.2.2" />
    <PackageReference Include="Serilog.Settings.Configuration" Version="3.0.1" />
    <PackageReference Include="Serilog.Sinks.MSSqlServer" Version="5.1.2" />
    <PackageReference Include="Stripe.net" Version="26.0.0" />
    <PackageReference Include="Syncfusion.EJ2.AspNet.Core" Version="17.1.0.48" />
  </ItemGroup>
</Project>

StackTrace:

System.InvalidOperationException: No database provider has been configured for this DbContext. A provider can be configured by overriding the DbContext.OnConfiguring method or by using AddDbContext on the application service provider. If AddDbContext is used, then also ensure that your DbContext type accepts a DbContextOptions<TContext> object in its constructor and passes it to the base constructor for DbContext.
   at Microsoft.EntityFrameworkCore.Internal.DbContextServices.Initialize(IServiceProvider scopedProvider, IDbContextOptions contextOptions, DbContext context)
   at Microsoft.EntityFrameworkCore.DbContext.get_InternalServiceProvider()
   at Microsoft.EntityFrameworkCore.DbContext.Microsoft.EntityFrameworkCore.Infrastructure.IInfrastructure<System.IServiceProvider>.get_Instance()
   at Microsoft.EntityFrameworkCore.Internal.InternalAccessorExtensions.GetService[TService](IInfrastructure`1 accessor)
   at Microsoft.EntityFrameworkCore.Infrastructure.AccessorExtensions.GetService[TService](IInfrastructure`1 accessor)
   at Microsoft.EntityFrameworkCore.Design.Internal.DbContextOperations.CreateContext(Func`1 factory)
   at Microsoft.EntityFrameworkCore.Design.Internal.DbContextOperations.CreateContext(String contextType)
   at Microsoft.EntityFrameworkCore.Design.Internal.MigrationsOperations.AddMigration(String name, String outputDir, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.AddMigrationImpl(String name, String outputDir, String contextType)
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.AddMigration.<>c__DisplayClass0_1.<.ctor>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.<>c__DisplayClass3_0`1.<Execute>b__0()
   at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
No database provider has been configured for this DbContext. A provider can be configured by overriding the DbContext.OnConfiguring method or by using AddDbContext on the application service provider. If AddDbContext is used, then also ensure that your DbContext type accepts a DbContextOptions<TContext> object in its constructor and passes it to the base constructor for DbContext.

[ajcvickers]

@ajitgoel The main issue here is that ASP.NET defines a specific pattern for use by tooling like EF Core. This pattern is shown here: https://docs.microsoft.com/en-us/aspnet/core/fundamentals/host/web-host?view=aspnetcore-2.2

Since your Main does everything in one method it means tooling cannot use the well-known pattern to create you context instance. Refactoring to meet the expected pattern should fix this.

Note for triage: I wasn't able to find a place that clearly states this in the EF docs.

[ajcvickers]

Update: This is what I was looking for: https://docs.microsoft.com/en-us/ef/core/miscellaneous/cli/dbcontext-creation

[ajitgoel]

Thank you @ajcvickers , I learnt something today.

[ajcvickers]

Note from triage: docs issues: dotnet/EntityFramework.Docs#1464 and dotnet/EntityFramework.Docs#1050