Comments from @shaochuancs and @Helen are about nodejs http client.
If you need a server implementation of HTTP pipeline that depends entirely on the the nodejs core library.
HTTP server-side pipelining support is built-in and already OK in nodejs (I've just made the tests on tested on v5.5.0 v7.0.9 and v6.2.1).
To test pipelining support simply chain two HTTP request in the same tcp/ip connection. You can do it using telnet or netcat (nc).
# telnet, connecting to port 80, chaining 2 requests on /login
# for host foo.com
(echo -en "GET /login HTTP/1.1\nHost: foo.com\nConnection: keep-alive\n\nGET /login HTTP/1.1\nHost: foo.com\n\n"; sleep 10) | telnet localhost 80
# same thing using printf and netcat
printf "GET /login HTTP/1.1\r\nHost: foo.com\r\nConnection: keep-alive\r\n\r\nGET /login HTTP/1.1\r\nHost: foo.com\r\n\r\n" | nc -q 10 localhost 80
Then count the number of responses, you should get 2 (or 1 if pipelining is not supported). Search for 'HTTP/1.1 200 OK' in the output.