Where does this error come from?

I sometimes get this error from an HTTP GET with "ureq":

Network Error: Error encountered in the status line: timed out reading response

Where does that come from? Where is that error text? It's nowhere in Github.

A Google search shows this message in a Rust program called innernet, which I am not using.

Someone else reported that in a fetch from a Debian repository.

I'm seeing it from a AWS server front-ended by Akamai, used for Second Life assets.

I think this means that an HTTP connection was established, with TLS handshake successful, but no HTTP status line and content showed up, after which the connection timed out. This is the sort of thing that might happen with a CDN where the HTTPS handshake takes place at the perimeter, and then whatever was supposed to serve the content didn't show up.

But who generated the text "Error encountered from the status line"? A Github search of "ureq" does not turn it up.

The error message is from ureq itself:

and

I just happened to get lucky by searching for a partial line.

Ah, thanks. I'd been searching for "Error encountered in the status line", with a no find. But that message is built up from multiple small pieces.

I might file an issue for ureq suggesting that those messages have a context that they're talking about the HTTP header, not something going wrong at the TLS or DNS level. This is a rare situation, but when it comes up, it means that some middlebox such as a cache or proxy has messed up, and those problems are always tough to diagnose.