AngularJS JSONP GET Example

This is an example of a cross domain GET request using JSONP, the most common way to get data. Like the previous example using CORS, this too uses requires the server to be ‘aware’ of request so it can reply with the JSONP callback method.

The “P” in the JSONP actually stands for padding, which really means “Named Function”. You pass along a named javascript function that tells the server to wrap its response and when it responds your data is neatly wrapped with a helper function. This gets around the Same Origin Policy since <script> tags are ok’d for cross domain execution, which is how we can include JS libs from CDNs and other sources.

This method does require control over the request destination, or the site itself has to support a JSONP callback. This is just a javascript function returned from a ‘black box’, so there are some serious security concerns (but you’re not sending sensitive data via GET, right?). Also, we should note that this method have VERY limited support for reporting errors. Most people work around this by timing a response check and timeouts (which someday we may blog about).