h2c server-push client example

recv_push_async_await.py

import re
import struct
import curio
import curio.socket as socket
import h11
import h2.connection
from urllib.parse import urlparse


async def push_test(url, callback):
    pc = urlparse(url)
    target = pc.path
    if pc.query:
        target += "?" + pc.query
    addr = (pc.netloc, 80)
    nc = re.match(r"(.*):(\d+)", pc.netloc)
    if nc:
        addr = (nc.group(1), int(nc.group(2)))

    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    con = h11.Connection(our_role=h11.CLIENT)
    con2 = h2.connection.H2Connection()

    await sock.connect(addr)
    async with sock:
        s = con.send(h11.Request(method="GET",
                                 target=target,
                                 headers=[("Host", "localhost"),
                                          ("Connection", "Upgrade, HTTP2-Settings"),
                                          ("Upgrade", "h2c"),
                                          ("HTTP2-Settings", con2.initiate_upgrade_connection())]))
        s += con.send(h11.EndOfMessage())
        await sock.send(s)
        while True:
            d = await sock.recv(8192)
            if len(d):
                con.receive_data(d)
            else:
                break

            ev = con.next_event()
            if isinstance(ev, h11.InformationalResponse):
                break
            elif ev is h11.NEED_DATA:
                continue
            else:
                raise Exception("unexpected event")

        # Switched to HTTP2
        connected = True
        await sock.send(con2.data_to_send())
        data = con.trailing_data[0]

        async def pinger():
            i = 0
            while connected:
                con2.ping(struct.pack("!Q", i))
                await sock.send(con2.data_to_send())
                await curio.sleep(2)
                i += 1
        await curio.spawn(pinger())

        while True:
            for ev in con2.receive_data(data):
                callback(ev)
            data = await sock.recv(8192)
            if len(data) == 0:
                break
        connected = False

curio.run(push_test("http://localhost:8080/pushing", print))

recv_push_eventlet.py

import re
import struct
import eventlet
import h11
import h2.connection
try:
	from urllib.parse import urlparse
except:
	from urlparse import urlparse

def push_test(url, callback):
	pc = urlparse(url)
	target = pc.path
	if pc.query:
		target += "?" + pc.query
	addr = (pc.netloc, 80)
	nc = re.match(r"(.*):(\d+)", pc.netloc)
	if nc:
		addr = (nc.group(1), int(nc.group(2)))

	sock = eventlet.connect(addr)
	con = h11.Connection(our_role=h11.CLIENT)
	con2 = h2.connection.H2Connection()

	s = con.send(h11.Request(method="GET",
		target=target,
		headers=[("Host", "localhost"),
		("Connection", "Upgrade, HTTP2-Settings"),
		("Upgrade", "h2c"),
		("HTTP2-Settings", con2.initiate_upgrade_connection())]))
	s += con.send(h11.EndOfMessage())
	sock.send(s)
	while True:
		d = sock.recv(8192)
		if len(d):
			con.receive_data(d)
		else:
			return # EOF
		ev = con.next_event()
		if isinstance(ev, h11.InformationalResponse):
			break
		elif ev is h11.NEED_DATA:
			continue
		else:
			return # Unexpected event

	# Switched to HTTP2
	connected = True
	sock.send(con2.data_to_send())
	data = con.trailing_data[0]

	def pinger():
		i = 0
		while connected:
			con2.ping(struct.pack("!Q", i))
			sock.send(con2.data_to_send())
			eventlet.sleep(2)
			i += 1
	
	eventlet.spawn(pinger)

	while True:
		for ev in con2.receive_data(data):
			callback(ev)
		data = sock.recv(8192)
		if len(data) == 0:
			break
	connected = False

push_test("http://localhost:8080/pushing", print)