Configure services and HTTP pipeline

- [Voiceover] It's now time to configure…the HTTP Pipeline and needed services.…Prior versions of ASP.net used several files…from app start, the global ASAX and start-up…to configure the application.…This all has been compressed down into one file.…By default it's called startup.cs…and it's specified by the web host builder.…The constructor loads the application configuration,…we've already looked at that, and then…it configures services used by the application.…

This is also where you populate…the dependency injection container,…which we'll talk about in the next section.…And then finally, it configures the HTTP Pipeline.…ASP.net core is an opt-in model,…so by default, nothing is available,…and if you want to add in services like mvc…or mvc core, which is a streamlined version…of the mvc service just for restful services,…static file support for any of those other items,…you must opt in.…

The app_start contains very little in a web API 2.2 project,…really just the web API routing config,…and authentication if it's being used.…