I'm hitting a strange problem with a route that is using the servlet
component to send a large stream of data in its response.
This is part of a route that uses the REST DSL which is set up like this:
restConfiguration().component("servlet").host("0.0.0.0");
The route sets the response body as an PipedInputStream and then (in a
separate thread) writes to that InputStream and eventually closes it.
The expectation is that as the response size is unknown the data will be
chunked and response returned to the client immediately and the client
will start to consume the data immediately.
When using curl as the client it seems to be working correctly, and I
see a 'Transfer-Encoding: chunked' header in the response.
However my real client is Apache HttpAsyncClient and with that what I'm
seeing is that the response is not returned until all the data is
written, and instead of a 'Transfer-Encoding: chunked' header I see a
'Content-Length: 19196336' header suggesting that Camel has waited for
the entire content to be written so that it can set the Content-Length.
I tried manually setting the 'Transfer-Encoding: chunked' in the
response message but it did not appear and instead I saw the
Content-Length header.
I've got HttpAsyncClient working in a test example to prove that it can
received the response asynchronously, so I think (but can't be sure)
that the problem is on the server (Camel) side.
What can explain this different behaviour from the same service when
using different clients?
