EFCore 迁移问题 Azure Function 使用 Clean Architecture 构建的应用程序

Question

我创建了一个Azure Function App ，使用.Net Core和 Clean Architecture，定义如下：

这就是我的Project Structure的样子：

实体框架在Infrastructure Layer中实现，如下所示：

基础设施中的 ApplicationDbContext 代码和 DI

namespace AppFunctions.Infrastructure.Persistence
{
    public class ApplicationDbContext : DbContext, IApplicationDbContext
    {
        public ApplicationDbContext(DbContextOptions options) : base(options)
        {
        }

        public DbSet<Product> Products { get; set; }

        public Task<int> SaveChangesAsync()
        {
            return base.SaveChangesAsync();
        }
    }
}

namespace AppFunctions.Infrastructure
{
    public static class DependencyInjection
    {
        public static IServiceCollection AddInfrastructure(this IServiceCollection services, IConfiguration configuration)
        {
            services.AddDbContext<ApplicationDbContext>(options =>
                    options.UseSqlServer(
                        configuration.GetConnectionString("DefaultConnection"),
                        b => b.MigrationsAssembly(typeof(ApplicationDbContext).Assembly.FullName)),ServiceLifetime.Transient);

            services.AddScoped<IApplicationDbContext>(provider => provider.GetRequiredService<ApplicationDbContext>());
            return services;
        }
    }
}

而这个 DI 注册在Azure Function App's Startup class是这样的：

[assembly: FunctionsStartup(typeof(StartUp))]
namespace JSStockValuationFrameworkAppFunctions
{
    internal class StartUp : FunctionsStartup
    {
        public override void Configure(IFunctionsHostBuilder builder)
        {
            ConfigureServices(builder.Services);
        }

        private void ConfigureServices(IServiceCollection services)
        {
            // Configurations
            IConfigurationRoot configuration = new ConfigurationBuilder()
                .SetBasePath(Directory.GetCurrentDirectory())
                .AddJsonFile($"local.settings.json", optional: true, reloadOnChange: true)
                .AddEnvironmentVariables()
                .Build();

            services.AddApplication();
            services.AddInfrastructure(configuration);
        }
    }
}

在这里，我面临着迁移问题。 我尝试了以下命令：

dotnet ef migrations add "SampleMigration" --project Infrastructure --startup-project FunctionApp --output-dir Persistence\Migrations

但是得到这个错误：

MSBUILD : error MSB1009: Project file does not exist.
Switch: C:\FrameworkAppFunctions\AppFunctions
Unable to retrieve project metadata. Ensure it's an SDK-style project. If you're using a custom BaseIntermediateOutputPath or MSBuildProjectExtensionsPath values, Use the --msbuildprojectextensionspath option.

Answer 1

SDK-style project. If you're using a custom BaseIntermediateOutputPath or MSBuildProjectExtensionsPath values, Use the --msbuildprojectextensionspath option. ```

• 它可以通过从包含解决方案文件的父文件夹运行do.net ef dbcontext scaffold <list_of_options>命令来解决。 此外，使用cd..并重新运行将为您提供结果的命令。
• 此外，我可以看到您在命令（ Persistence\Migrations ）中使用反斜杠\将所有内容更改为正斜杠/
• 欲了解更多信息，您可以通过此链接拨打 go。

Answer 2

该问题已通过以下代码解决IDesignTimeDbContextFactory

namespace Infrastructure.Persistence.Configuration
{
    public class ApplicationDbContextFactory : IDesignTimeDbContextFactory<ApplicationDbContext>
    {
        public ApplicationDbContext CreateDbContext(string[] args)
        {
            var optionsBuilder = new DbContextOptionsBuilder<ApplicationDbContext>();
            optionsBuilder.UseSqlServer("Connection string goes here...");

            return new ApplicationDbContext(optionsBuilder.Options);
        }
    }
}