Function get_streaming 

pub fn get_streaming(
    url: &str,
    bearer: Option<&str>,
    sink: &mut dyn FnMut(&[u8]) -> bool,
    progress: &'_ mut dyn FnMut(u64, Option<u64>),
    cancel: &AtomicBool,
) -> Result<(), HttpError>

Hands each chunk to sink as it arrives; sink returns false to abort. The bearer token is a credential and is never logged.