HTTP2 Jetty Server does not send back content-length

[CaoManhDat]

Jetty version 9.4.24.v20191120

Java version Java 11

Question On requesting to a plain text HTTP2 (h2c) Jetty Server, the response doesn't include content-length in the header. But with that same server on requesting using HTTP/1.1, the server does return content-legth.
I understand that content-length is not required for HTTP2 protocol. But it will be very helpful for client for handling the response if content-length is available. So do Jetty have any configuration to enforce server to return content-length in the header?

[sbordet]

You are correct that currently we don't add the Content-Length header if we know in advance the total content length.

Can you expand on how this header will be useful to a HTTP/2 client?

[CaoManhDat]

Few examples

• use it for BufferingResponseListener, so it can know exactly how much memory it needs to allocate.
• in my case we need to choose wether to use BufferingResponseListener (which doesn't need to spin a new thread to wait for data from other's side) or InputStreamResponseListener
• same idea from http2 spec community: Encouraging Content-Length headers httpwg/http2-spec#558

[CaoManhDat]

Thanks!