I am looking to try and use Cloud SQL in GCP to host the PostGreSQL DB that Chef Automate and Infra use.
Now my question is does anyone have any experience in doing this and is this something this is officially supported by Chef, as the documentation around it doesn't really say either way? Any info would be much appreciated.
Both product being under commercial subscription, talking with a Chef representative sounds the way to go for your questions.
There's Chef employees around here, but if it's not in the documentation, I doubt anyone will officially vouch for it on a forum in name of the company, if you're after an answer about "officially supported" the best path is asking Chef officially.
All in all, I see no reason you technically couldn't as long as GCP managed postgresql engine match the required version for infra and automate, but that's just a technical point of view and I can't answer on the possible support around it.