WinHttp is the new Win32 HTTP API that replaces the IXMLHttpRequest2 (IXHR2) and IMessageWebSocket APIs. WinHttp is a lower-level API than IXHR2 is and thus lacks some features as compared to IXHR2, such as content caching, cookies, automatic XBOX services token insertion, and automatic security enforcement. In return, WinHttp is much more performant by being in-process, having less overhead, and avoiding excessive memory copies. In addition, WinHttp supports HTTP/1.1, HTTP/2, and WebSockets, all in one API, and includes features that are missing from IXHR2, such as chunked uploads.
XCurl is an HTTP API for the Microsoft Game Development Kit (GDK). XCurl provides a simpler API through an adapter over WinHttp. The XCurl API surface broadly matches libCurl. XCurl simplifies title development by handling security best practices automatically and by handling network initialization.
In addition to WinHttp, the XBOX Services API (XSAPI) provides the simple http_call set of APIs that you can use to make REST HTTP requests to your own custom servers. We recommend using XSAPI for any REST requests that your title makes to your own services and to XBOX services.
For more information about XSAPI, see Getting started with XBOX Services APIs.
The GDK includes a SimpleWinHttp sample that abstracts WinHTTP usage into a simple Microsoft Game Development Kit (GDK) asynchronous model. We recommend that you use this sample as a starting point for your own WinHTTP implementation because it covers many of the details involved in building a secure and robust WinHTTP integration.
For more information about how to use XCurl or WinHttp, see HTTP and web sockets.
Network initialization
Your title is started as soon as possible during the Game OS startup process. You can start loading assets from the hard drive and begin initializing the graphics stack. However, your code is executing before the network services are started, which leads to a period of time where it’s not safe to use the Win32 network APIs. We define this time period as the network initialization period, after which the network is considered initialized. Network initialization typically takes a few seconds, which can be noticeable in your code. Network initialization for XBOX One ERA titles would implicitly and arbitrarily stall otherwise real-time-safe network APIs, such asWSAStartup or bind. With Microsoft Game Development Kit (GDK) apps, network initialization is now an explicit concept that you must interact with to use any Win32 networking or security APIs.
Microsoft Game Development Kit (GDK) titles must wait until the XNetworkingConnectivityHint::networkInitialized Boolean is set to true before calling into any networking API in Winsock, WinHttp, IP Helper, BCrypt, WinCrypt, Schannel, or any other networking Win32 API. Calling into any of these APIs before the network is initialized results in indeterminate behavior up to and including random process crashes.
Furthermore, this same concept applies on all suspend/resume cycles. On suspend, Microsoft Game Development Kit (GDK) titles should close all network and security handles. Microsoft Game Development Kit (GDK) titles should then treat the resume handler the same as the initial title launch from a networking perspective and again wait for the network to become initialized.
For more information, including code examples showing how to wait for network initialization, see Network initialization and connectivity.