Startup.cs

using System;
using HotChocolate.Configuration;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using OpenCodeFoundation.OpenTelemetry;
using Serilog;

namespace OpenCodeFoundation.ESchool.ApiGateways.ESchool.GraphQL
{
    public class Startup
    {
        public const string Enrolling = "enrolling";
        public const string CourseRegistration = "courseregistration";

        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddCors();

            services.AddHttpClient(Enrolling, c =>
                c.BaseAddress = new Uri("http://enrolling.api/graphql"));

            services.AddHttpClient(CourseRegistration, c =>
                c.BaseAddress = new Uri("http://courseregistration.api/graphql"));

            services
                .AddGraphQLServer()
                .AddRemoteSchema(Enrolling)
                .AddRemoteSchema(CourseRegistration);

            services.AddOpenTelemetryIntegration();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseSerilogRequestLogging();

            app.UseCors(o => o
                .AllowAnyHeader()
                .AllowAnyMethod()
                .AllowAnyOrigin());

            app.UseRouting();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapGraphQL();
            });
        }
    }
}