Function length_differs 

fn length_differs(did: &str, declared: u64, received: u64) -> Response

The answer to an upload body that is not the length its Content-Length declared. atproto’s blob specification: “If the actual blob upload size differs from the Content-Length header, the server should reject the upload.” A body that runs past its length is refused at the frame that runs past it, and no later frame is read.