I'm building a website for a client (real estate), and on the website are links to a different website (adverts for properties). My client routinely activates and deactivates these adverts when he rents out a certain property.
The hrefs on my links look something like this:
<a href="https://domain.xx/estate/idxx/des-crip-tion-xx-xx-x-xx/">. If the advert is indeed active, it just takes them to the advert. If it is not active, however, the website in question redirects the user to https://domain.xx/estate-for-rent/city/, effectively sending the users to my client's competition.
I wish to implement some logic where, before handing the users over to the other website, the server checks to see if it is redirected to https://domain.xx/estate-for-rent/city/, or some similar logic, and if so, uses preventDefault, or something, and notifies the user that the advert is not available instead of sending them to the other website.
I wonder if I can use the fact that only if the advert is active does the resulting url in the users browser window (after they've been directed to the other website) match the url in my href. Can i somehow get the server to try to access the url in my href, and have it see where it gets redirected, and then do something based on that? On the back-end, I'm running NodeJS with Express by the way, and if it matters, I'm relying heavily on EJS for templating. Thanks in advance for any help!
This sounds more like a problem you could solve on the client as opposed to the server. For example, at a high level here's how I would do it:
click event for each link (really simple to do a catch-all with jQuery)HEAD request via AJAX to the destination URL (this would be much more efficient than a GET but depends on the external service supporting this verb)2xx allow redirect, 3xx pop a message and block)