30 Oct 2012
How to override Facebook and LinkedIn’s cache
In case you don’t know, both Facebook and LinkedIn hold the contents of the site link that you send them for a week before they purge that and look for new content in that link.
I had a WordPress site I was working with and using Open Graph Meta Tags’ og:image to get the post’s Featured Image but that wasn’t working so I switched the header code to look for the first image in the post and that worked.
In between the switching, I learned about the caching systems by reading the developer forums and doing my own field testing. Below is an interaction I had a with a client and it was written in a rush. I hope it helps someone reading this post.
I don’t understand why I would need to use those extensions in order for the image to be pulled by Facebook and LinkedIn - for this page only?
First I shared with you that Facebook and LinkedIn both cache websites (links) for a week and they won’t find new images you upload to a post you made in that one week span (and oops the images don’t work) but then you try again and you get the same images not working because it’s still in the same week, so uploading the same image with different name won’t change what Facebook and LinkedIn have in their cache for that link on your website.
So…to force Facebook and LinkedIn to go and find a new image within that week span, you need to use those extensions on that link. Facebook ( /?t=0 ) and LinkedIn ( /?v=1 ) If you create a new post on your website (i.e. new link), then it’s something new to Facebook/LinkedIn and sure, they’ll want to find it.
If it’s been a week since the time of trying that (oops it doesn’t want to find my new images) old link, then by then these developer forums say they will empty their cache and look for new content for those links they already know.