Unfortunately if domain is not whitelisted in whitelisted_generic_onebox.rb it won’t be oneboxed. I am doing a test with my domain, and I don’t even receive GET request. I also tried to test with rake server as suggested here GitHub - discourse/onebox: (DEPRECATED) A gem for turning URLs into website previews and it is the same behaviour.
The domain has to be whitelisted it seems. And it is stated in onebox documentation
The domain must be whitelisted
I and I could not find you are doing any whitelisting in the discourse codebase.
I am trying to onebox jpg image. I have my local installation of discourse on VirtualBox where I am trying to make this work. By the way there is a bug in onebox implementation. Here’s the pull request: https://github.com/discourse/onebox/pull/331
I managed to onebox with rake server when I add my domain to whitelisted_generic_onebox.rb. Otherwise it doesn’t work. As I said earlier, onebox doesn’t even try to GET if the domain is not whitelisted.
Unfortunately I can not share the link, but the effect can be observed if you remove 23hq from onebox whitelist and test this url: 23: Kai Krause - mprove
It has oembed type of ‘photo’