socket发送请求,协程
1.socket发送请求
1 #发送请求的方式 2 3 #方式一 4 import requests 5 6 ret = requests.get("https://www.baidu.com/s?wd=abc") 7 8 print(ret.text) 9 10 11 #方式二 12 13 import socket 14 15 client = socket.socket() 16 client.connect(("www.baidu.com",80)) 17 client.sendall(b"GET /s?wd=alex HTTP/1.0\r\nhost:www.baidu.com\r\n\r\n") 18 chunk_list = [] 19 while True: 20 chunk = client.recv(8096) 21 if not chunk: 22 break 23 chunk_list.append(chunk) 24 25 body = b"".join(chunk_list) 26 print(body.decode("utf-8"))
单线程的并发
1 import socket 2 import select 3 4 client1 = socket.socket() 5 client1.setblocking(False)#百度创建链接:非阻塞 6 7 try: 8 client1.connect(("www.baidu.com",80)) 9 except BlockingIOError as e: 10 pass 11 12 client2 = socket.socket() 13 client2.setblocking(False) 14 15 try: 16 client2.connect(("www.baidu.com",80)) 17 except BlockingIOError as e: 18 pass 19 20 client3 = socket.socket() 21 client3.setblocking(False) 22 23 try: 24 client3.connect(("www.baidu.com",80)) 25 except BlockingIOError as e: 26 pass 27 28 socket_list = [client1,client2,client3] 29 conn_list = [client1,client2,client3] 30 31 while True: 32 rlist,wlist,elist = select.select(socket_list,conn_list,[],0.005) 33 for sk in wlist: 34 if sk == client1: 35 sk.sendall(b'GET /s?wd=alex HTTP/1.0\r\nhost:www.baidu.com\r\n\r\n') 36 elif sk == client2: 37 sk.sendall(b'GET /web?query=fdf HTTP/1.0\r\nhost:www.sogou.com\r\n\r\n') 38 else: 39 sk.sendall(b'GET /s?wd=alex HTTP/1.0\r\nhost:www.oldboyedu.com\r\n\r\n') 40 conn_list.remove(sk) 41 for sk in rlist: 42 chunk_list = [] 43 while True: 44 try: 45 chunk = sk.recv(8096) 46 if not chunk: 47 break 48 chunk_list.append(chunk) 49 except BlockingIOError as e: 50 break 51 body = b"".join(chunk_list) 52 53 sk.close() 54 socket_list.remove(sk) 55 if not socket_list: 56 break
2.协程
1 import greenlet 2 3 def f1(): 4 print(111) 5 g2.switch() 6 print(222) 7 g2.switch() 8 9 def f2(): 10 print(333) 11 g1.switch() 12 print(444) 13 14 g1 = greenlet.greenlet(f1) 15 g2 = greenlet.greenlet(f2) 16 g1.switch()
协程的IO切换
1 from gevent import monkey 2 monkey.patch_all() 3 import requests 4 import gevent 5 6 def get_page1(url): 7 ret = requests.get(url) 8 print(url,ret.content) 9 10 def get_page2(url): 11 ret = requests.get(url) 12 print(url,ret.content) 13 14 def get_page3(url): 15 ret = requests.get(url) 16 print(url,ret.content) 17 18 gevent.joinall( 19 gevent.spawn(get_page1,'https://www.python.org/'), 20 gevent.spawn(get_page2, 'https://www.yahoo.com/'), 21 gevent.spawn(get_page3, 'https://github.com/') 22 23 )