private static K2Config LoadConfig(string[] args)
{
string APP_SETTINGS_OVERRIDE_FILENAME = $"appsettings.{Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT")}.json";
// build configuration ; https://stackoverflow.com/a/58594026
var builder = new ConfigurationBuilder() // configuration 순서 중요
.SetBasePath(GetBasePath()) // 파일을 읽기 전에 설정
.AddEnvironmentVariables() // 환경변수에 "K2:ServerId" 와 같은 형식의 값으로 사용 가능하도록
.AddJsonFile(APP_SETTINGS_FILENAME); // 환경변수 값을 json 으로 override 가능하도록
if (System.IO.File.Exists(APP_SETTINGS_OVERRIDE_FILENAME))
{
builder.AddJsonFile(APP_SETTINGS_OVERRIDE_FILENAME); // 환경에 따른 json override
}
builder.AddCommandLine(args); // 모든 설정은 다시 commandline argument 로 override 가능. ex) K2:ListeningPort=1111
var configuration = builder.Build();
var config = configuration.GetSection(K2Config.SECTION_NAME).Get <K2Config>();
if (config == null)
{
config = new K2Config(); // create default (development environment)
}
if (config.HasServerManager)
{ // ServerManager 로 동작하는 경우 ServerManagerAddress 는 항상 자기 자신이어야 한다. 잘못설정한 경우 crash 가 맞나?
config.ServerManagerAddress = $"{config.ServiceScheme}://localhost:{config.ListeningPort}";
}
return(config);
}
// Additional configuration is required to successfully run gRPC on macOS.
// For instructions on how to configure Kestrel and gRPC clients on macOS, visit https://go.microsoft.com/fwlink/?linkid=2099682
public static IHostBuilder CreateHostBuilder(string[] args, K2Config config)
{
return(Host.CreateDefaultBuilder(args)
.ConfigureWebHostDefaults(webBuilder =>
{
webBuilder
.UseKestrel(options =>
{
options.ListenAnyIP(config.ListeningPort);
})
.ConfigureServices(sc =>
{
var backendHeader = new Grpc.Core.Metadata();
backendHeader.Add(nameof(config.BackendGroupId), config.BackendGroupId); // key 는 소문자로 변환되어 들어간다
// K2Config 종속적인 resource 들 ; asp.net core 3.0 이후 직접 StartUp 에 parameter 를 전달할 수 없음 (https://andrewlock.net/avoiding-startup-service-injection-in-asp-net-core-3/)
sc.AddSingleton(config);
sc.AddSingleton(backendHeader);
})
.UseStartup <Startup>()
;
}));
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env, K2Config localConfig, RemoteConfig remoteConfig, ILogger <Startup> logger)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
}
// service blocker
app.Use(async(context, next) =>
{ // https://docs.microsoft.com/ko-kr/aspnet/core/fundamentals/middleware/write?view=aspnetcore-3.1#middleware-class
if (localConfig.HasServerManager == false && remoteConfig.Registered == false)
{ // 아직 grpc 서비스를 사용가능한 상태가 아님
logger.LogWarning($"not registered yet for {context.Request.Path}");
return;
}
await next();
});
// 여기(app.Use~ middleware) 순서 중요 ; https://docs.microsoft.com/ko-kr/aspnet/core/grpc/authn-and-authz?view=aspnetcore-3.1
app.UseRouting();
app.UseAuthentication();
app.UseAuthorization();
app.UseEndpoints(endpoints =>
{
// TODO: reflection 으로 endpoints.MapGrpcService 을 자동화
// backend services(managers)
if (localConfig.HasServerManager)
{
endpoints.MapGrpcService <Backend.ServerManagerBackend>();
}
if (localConfig.HasSessionManager)
{
endpoints.MapGrpcService <Backend.SessionManagerBackend>();
}
// hosts(backend client to backend service)
// backend server 의 명령(push)을 받을 backend host 들 ; disable 될 수 없다.(항상 manager 의 request 에 응답해야 한다)
endpoints.MapGrpcService <Backend.ServerHostBackend>();
endpoints.MapGrpcService <Backend.SessionHostBackend>();
// frontend services
if (localConfig.HasInitService)
{
endpoints.MapGrpcService <Frontend.InitService>();
}
if (localConfig.HasPushService)
{
endpoints.MapGrpcService <Frontend.PushService>();
}
if (localConfig.HasPushSampleService)
{
endpoints.MapGrpcService <Frontend.PushSampleService>();
}
if (localConfig.HasSimpleSampleService)
{
endpoints.MapGrpcService <Frontend.SimpleSampleService>();
}
endpoints.MapGet("/", async context =>
{
await context.Response.WriteAsync("invalid access");
});
});
}
