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Prefetching Mode - Facebook SDK for JavaScript - Documentation - Meta for Developers
Prefetching Mode
The method FB.Canvas.Prefetcher.setCollectionMode()
controls how statistics are collected on resources used by your application. This method influences whether those resources are fetched to the browser early; it can also be used to turn off Prefetching completely.
This method takes one of two constants as a parameter:
FB.Canvas.Prefetcher.COLLECT_AUTOMATIC
-- use default collection mode
FB.Canvas.Prefetcher.COLLECT_MANUAL
-- fully manual
See the Prefetching section for an overview of this feature.
Examples
To completely control which resources are reported to Facebook, for a given page load
FB.Canvas.Prefetcher.setCollectionMode(FB.Canvas.Prefetcher.COLLECT_MANUAL);
FB.Canvas.Prefetcher.addStaticResource("https://www.mydomain.com/foo.js");
// ...
Note
It is not necessary to call setCollectionMode to call addStaticResource ; in automatic mode, Facebook will automatically infer what other resources you are using that are important to fetch early.
You can use the staticresources
connection on the Graph API Application object to check which usage statistics are being collected.