Cross-Domain AJAX (CORS/JSONP)
Understand and apply techniques for making cross-domain AJAX requests using JSONP or configuring CORS headers on the server for secure data exchange.
Cross-Domain AJAX: The Challenge
When your website tries to fetch data from another website, it's called a cross-domain AJAX request. This is often tricky!
By default, web browsers have a security rule that prevents a webpage from making requests to a different domain than the one it originated from. This rule protects your data.
Understanding Same-Origin Policy
The security rule we just mentioned is called the Same-Origin Policy (SOP). It's a fundamental browser security feature.
SOP dictates that a web browser permits scripts contained in a first web page to access data in a second web page only if both web pages have the same origin (domain, protocol, and port).
- Example: A page from
mywebsite.comcannot fetch data fromapi.anotherdomain.comdirectly.
All lessons in this course
- Configuring AJAX Requests Effectively
- Handling AJAX Errors and Success
- Cross-Domain AJAX (CORS/JSONP)