If you load http://example.com and the HTML there includes an image tag that says '<img src="http://othersite.com/image.jpg">' it means your browser will connect to othersite.com and ask that site for the image. It will not ask example.com.
You can't use <object>, <iframe> etc tags to embed pictures in your Github README, so you don't get automatic updates there no matter what (i.e. images would only refresh on page load). I don't know if Github proxies and caches <img> contents, or how long they cache it for but I haven't personally seen any delays when I've updated images used in READMEs.
But to repeat: auto-updating will not work for Github-hosted content AFAIK.
Comments
Something I've always wondered about these shields... How do you ensure the platforms where users embed them don't cache the images in their CDNs?
Is it just a matter of setting headers?
If you load http://example.com and the HTML there includes an image tag that says '<img src="http://othersite.com/image.jpg">' it means your browser will connect to othersite.com and ask that site for the image. It will not ask example.com.
I'm asking about what happens when, for example, you embed a dynamic SVG badge in your GitHub readme.
Doesn't GitHub cache every image in their own CDN for security and control purposes?
You can't use <object>, <iframe> etc tags to embed pictures in your Github README, so you don't get automatic updates there no matter what (i.e. images would only refresh on page load). I don't know if Github proxies and caches <img> contents, or how long they cache it for but I haven't personally seen any delays when I've updated images used in READMEs.
But to repeat: auto-updating will not work for Github-hosted content AFAIK.