Because this error comes up now and then, and it’s a confusing one, I’ll just clarify what it’s saying. Obviously the error is related to the database query, but it’s not caused by the database query. DBConnection is reporting that the client exited. The client, in this scenario, is the Phoenix request process that initiated the request.
So the Phoenix request process exited and therefore DBConnection errored. A common cause for the Phoenix request to exit is a timeout. Timeouts are not handled by Phoenix at all, rather by Cowboy, which is why Phoenix didn’t log an error. Cowboy will time out a request by default in 60s of inactivity, but there are other options at play as well.
You can find the options here Nine Nines: cowboy_http(3)
You did add http: [protocol_options: [idle_timeout: :infinity]], which was the most likely fix, are you sure it’s in the right config file?
I’m also curious what you see on the browser side (I’m assuming you’re initiating this from a browser). Are you getting any response at all?
