liveBook · Manning

Simple request

As explained in Building Web APIs with ASP.NET Core

A simple request is a browser cross-origin HTTP request that meets the requirements for being sent without a preliminary permission check.

A simple request is a cross-origin HTTP request that the browser sends without first checking permission through a separate request. It must meet the browser’s requirements for a simple request, which include requirements concerning the method, headers, and content. section 3.1.1

The browser sends the request, receives the response, and checks whether its Access-Control-Allow-Origin header permits the script’s origin. This is a browser decision, not a server error. If the request does not qualify as simple, the browser first sends a preflight HTTP OPTIONS request. section 3.1.1

How Building Web APIs with ASP.NET Core covers it

How deep it goes
Explains the browser’s request-and-response check but defers the full requirements for qualifying as simple.
Examples
Contrasts a qualifying client-side HTTP request with one that triggers an HTTP OPTIONS preflight.
What you can do after
Evaluate/understand why a browser sends a cross-origin request directly or checks permission first.
How it connects
Connects simple requests to the same-origin policy, CORS, preflight requests, and the Access-Control-Allow-Origin header.
Cover of Building Web APIs with ASP.NET Core
liveBookmanning.com
Read Building Web APIs with ASP.NET Core on liveBook Get the book at manning.com

This explainer was generated by Manning's knowledge graph from the text of Building Web APIs with ASP.NET Core. The section links point to the parts of the book it draws on.