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A Crow app defines an interface to allow the developer access to all the different parts of the framework, without having to manually deal with each one.

An app allows access to the HTTP server (for handling connections), router (for handling URLs and requests), Middlewares (for extending Crow), among many others.

Crow has 2 different app types:


Has no middlewares.

App<m1, m2, ...>

Has middlewares.

Using the app

To use a Crow app, simply define crow::SimpleApp or crow::App<m1, m2 ...> if you're using middlewares.
The methods of an app can be chained. That means that you can configure and run your app in the same code line.

Or if you like your code neat


The run() method is blocking. To run a Crow app asynchronously run_async() should be used instead.


When using run_async(), make sure to use a variable to save the function's output (such as auto _a = app.run_async()). Otherwise the app will run synchronously.

For more info on middlewares, check out this page.

For more info on what functions are available to a Crow app, go here.