OpenIddict Startup Example (with postgres and custom password rules)

Startup.cs

using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.EntityFrameworkCore.Infrastructure;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore;

namespace MyApp.Api
{
    public class Startup
    {
        public IConfigurationRoot Configuration { get; }

        public Startup(IHostingEnvironment env)
        {
            var builder = new ConfigurationBuilder()
                .SetBasePath(env.ContentRootPath)
                .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
                .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
                .AddEnvironmentVariables();
            Configuration = builder.Build();
        }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddCors();  // <- ADD THIS

            services.AddMvc();
            
            services.AddEntityFramework()
                .AddEntityFrameworkNpgsql()
                .AddDbContext<ApplicationDbContext>(options =>
                    options.UseNpgsql(Configuration["Data:DefaultConnection"]));

            services.AddIdentity<ApplicationUser, IdentityRole>(o => {
                    o.Password.RequireDigit = false;
                    o.Password.RequireLowercase = false;
                    o.Password.RequireUppercase = false;
                    o.Password.RequireNonAlphanumeric = false;
                    o.Password.RequiredLength = 6;
                })
                .AddEntityFrameworkStores<ApplicationDbContext>()
                .AddDefaultTokenProviders()
                .AddOpenIddict(); // <- ADD THIS

            services.AddSingleton(Configuration);
            services.AddSingleton<IContextFactory, ContextFactory>();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole(Configuration.GetSection("Logging"));
            loggerFactory.AddDebug();

            app.UseCors(builder =>  // <- ADD THIS
                builder.AllowAnyHeader()
                        .AllowAnyMethod()
                        .AllowAnyOrigin()
            );

            app.UseOAuthValidation();  // <- ADD THIS
            app.UseMvc();
            app.UseOpenIddict();  // <- ADD THIS

        }
    }
}

Questions:

• What is added exactly to use Sqlite for development.
• Why does the tutorial differ from the offical one on OpenIddict github pages.
• What does ApplicationDbContext look like, is it unchanged?

Nowadays, only thing you need to is to take any of the openiddict examples (in the examples repo) is change:

options.UseSqlServer(...);

to

options.UseNpgsql(...)

then change your connectionstring to a valid postgresql one and you're done.