Tornado 【框架基础过程分析1】
一般web框架，同步模式下存在的问题
1、计算等待
sleep模拟，A用户需耗费计算量的情况下占用线程时，B用户处于等待状态
import tornado.ioloop import tornado.web class MainHandler(tornado.web.RequestHandler): def get(self): import time time.sleep(10) self.write("Hello, world") class IndexHandler(tornado.web.RequestHandler): def get(self): self.write("Index") application = tornado.web.Application([ (r"/main", MainHandler), (r"/index", IndexHandler), ]) if __name__ == "__main__": application.listen(8888) tornado.ioloop.IOLoop.instance().start()
2、IO等待
写文件 / 网络返回等请求，A用户占用线程，B用户等待
import tornado.ioloop import tornado.web class MainHandler(tornado.web.RequestHandler): def get(self): import requests requests.get('http://www.google.com') self.write('xxxxx') class IndexHandler(tornado.web.RequestHandler): def get(self): self.write("Index") application = tornado.web.Application([ (r"/main", MainHandler), (r"/index", IndexHandler), ]) if __name__ == "__main__": application.listen(8888) tornado.ioloop.IOLoop.instance().start()
Tornado的解决方式---异步非阻塞
Future对象 + gen.coroutine装饰器 + yield生成器
1、计算等待
import tornado.ioloop import tornado.web from tornado import gen from tornado.concurrent import Future import time class MainHandler(tornado.web.RequestHandler): @gen.coroutine def get(self): future = Future() # 特殊的形式等待5s tornado.ioloop.IOLoop.current().add_timeout(time.time() + 5, self.done) yield future def done(self, *args, **kwargs): self.write('Main') self.finish() class IndexHandler(tornado.web.RequestHandler): def get(self): self.write("Index") application = tornado.web.Application([ (r"/main", MainHandler), (r"/index", IndexHandler), ]) if __name__ == "__main__": application.listen(8888) tornado.ioloop.IOLoop.instance().start()
2、IO中的网络请求
import tornado.ioloop import tornado.web from tornado import gen class MainHandler(tornado.web.RequestHandler): @gen.coroutine def get(self): from tornado import httpclient http = httpclient.AsyncHTTPClient() yield http.fetch("http://www.google.com", self.done) def done(self, *args, **kwargs): self.write('Main') self.finish() class IndexHandler(tornado.web.RequestHandler): def get(self): self.write("Index") application = tornado.web.Application([ (r"/main", MainHandler), (r"/index", IndexHandler), ]) if __name__ == "__main__": application.listen(8888) tornado.ioloop.IOLoop.instance().start()
Tornado的请求挂起
1、用yield结合Future对象来挂起请求
import tornado.ioloop import tornado.web from tornado import gen from tornado.concurrent import Future future = None class MainHandler(tornado.web.RequestHandler): @gen.coroutine def get(self): global future future = Future() future.add_done_callback(self.done) yield future def done(self, *args, **kwargs): self.write('Main') self.finish() class IndexHandler(tornado.web.RequestHandler): def get(self): global future future.set_result(None) self.write("Index") application = tornado.web.Application([ (r"/main", MainHandler), (r"/index", IndexHandler), ]) if __name__ == "__main__": application.listen(8888) tornado.ioloop.IOLoop.instance().start()
自己实现一个异步非阻塞框架
1、select和socket先实现同步阻塞式web框架
import socket import select class HttpRequest(object): """ 用户封装用户请求信息 """ def __init__(self, content): """ :param content:用户发送的请求数据：请求头和请求体 """ self.content = content self.header_bytes = bytes() self.body_bytes = bytes() self.header_dict = {} self.method = "" self.url = "" self.protocol = "" self.initialize() self.initialize_headers() def initialize(self): temp = self.content.split(b'\r\n\r\n', 1) if len(temp) == 1: self.header_bytes += temp else: h, b = temp self.header_bytes += h self.body_bytes += b @property def header_str(self): return str(self.header_bytes, encoding='utf-8') def initialize_headers(self): headers = self.header_str.split('\r\n') first_line = headers[0].split(' ') if len(first_line) == 3: self.method, self.url, self.protocol = headers[0].split(' ') for line in headers: kv = line.split(':') if len(kv) == 2: k, v = kv self.header_dict[k] = v # class Future(object): # def __init__(self): # self.result = None def main(request): return "main" def index(request): return "indexasdfasdfasdf" routers = [ ('/main/',main), ('/index/',index), ] def run(): sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) sock.bind(("127.0.0.1", 9999,)) sock.setblocking(False) sock.listen(128) inputs = [] inputs.append(sock) while True: rlist,wlist,elist = select.select(inputs,[],[],0.05) for r in rlist: if r == sock: """新请求到来""" conn,addr = sock.accept() conn.setblocking(False) inputs.append(conn) else: """客户端发来数据""" data = b"" while True: try: chunk = r.recv(1024) data = data + chunk except Exception as e: chunk = None if not chunk: break # data进行处理：请求头和请求体 request = HttpRequest(data) # 1. 请求头中获取url # 2. 去路由中匹配，获取指定的函数 # 3. 执行函数，获取返回值 # 4. 将返回值 r.sendall(b'alskdjalksdjf;asfd') import re flag = False func = None for route in routers: if re.match(route[0],request.url): flag = True func = route[1] break if flag: result = func(request) r.sendall(bytes(result,encoding='utf-8')) else: r.sendall(b"404") inputs.remove(r) r.close() if __name__ == '__main__': run()
2、自定义一个对象来挂起请求
import socket import select class HttpRequest(object): """ 用户封装用户请求信息 """ def __init__(self, content): """ :param content:用户发送的请求数据：请求头和请求体 """ self.content = content self.header_bytes = bytes() self.body_bytes = bytes() self.header_dict = {} self.method = "" self.url = "" self.protocol = "" self.initialize() self.initialize_headers() def initialize(self): temp = self.content.split(b'\r\n\r\n', 1) if len(temp) == 1: self.header_bytes += temp else: h, b = temp self.header_bytes += h self.body_bytes += b @property def header_str(self): return str(self.header_bytes, encoding='utf-8') def initialize_headers(self): headers = self.header_str.split('\r\n') first_line = headers[0].split(' ') if len(first_line) == 3: self.method, self.url, self.protocol = headers[0].split(' ') for line in headers: kv = line.split(':') if len(kv) == 2: k, v = kv self.header_dict[k] = v class Future(object): def __init__(self): self.result = None F = None def main(request): global F F = Future() return F def stop(request): global F F.result = b"xxxxxxxxxxxxx" return "stop" def index(request): return "indexasdfasdfasdf" routers = [ ('/main/',main), ('/index/',index), ('/stop/',stop), ] def run(): sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) sock.bind(("127.0.0.1", 9999,)) sock.setblocking(False) sock.listen(128) inputs = [] inputs.append(sock) async_request_dict = { # 'socket': futrue } while True: rlist,wlist,elist = select.select(inputs,[],[],0.05) for r in rlist: if r == sock: """新请求到来""" conn,addr = sock.accept() conn.setblocking(False) inputs.append(conn) else: """客户端发来数据""" data = b"" while True: try: chunk = r.recv(1024) data = data + chunk except Exception as e: chunk = None if not chunk: break # data进行处理：请求头和请求体 request = HttpRequest(data) # 1. 请求头中获取url # 2. 去路由中匹配，获取指定的函数 # 3. 执行函数，获取返回值 # 4. 将返回值 r.sendall(b'alskdjalksdjf;asfd') import re flag = False func = None for route in routers: if re.match(route[0],request.url): flag = True func = route[1] break if flag: result = func(request) if isinstance(result,Future): async_request_dict[r] = result else: r.sendall(bytes(result,encoding='utf-8')) inputs.remove(r) r.close() else: r.sendall(b"404") inputs.remove(r) r.close() for conn in async_request_dict.keys(): future = async_request_dict[conn] if future.result: conn.sendall(future.result) conn.close() del async_request_dict[conn] inputs.remove(conn) if __name__ == '__main__': run()
3、触发定时器回来处理刚才挂起的请求
import socket import select import time class HttpRequest(object): """ 用户封装用户请求信息 """ def __init__(self, content): """ :param content:用户发送的请求数据：请求头和请求体 """ self.content = content self.header_bytes = bytes() self.body_bytes = bytes() self.header_dict = {} self.method = "" self.url = "" self.protocol = "" self.initialize() self.initialize_headers() def initialize(self): temp = self.content.split(b'\r\n\r\n', 1) if len(temp) == 1: self.header_bytes += temp else: h, b = temp self.header_bytes += h self.body_bytes += b @property def header_str(self): return str(self.header_bytes, encoding='utf-8') def initialize_headers(self): headers = self.header_str.split('\r\n') first_line = headers[0].split(' ') if len(first_line) == 3: self.method, self.url, self.protocol = headers[0].split(' ') for line in headers: kv = line.split(':') if len(kv) == 2: k, v = kv self.header_dict[k] = v class Future(object): def __init__(self,timeout=0): self.result = None self.timeout = timeout self.start = time.time() def main(request): f = Future(5) return f def index(request): return "indexasdfasdfasdf" routers = [ ('/main/',main), ('/index/',index), ] def run(): sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM) sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) sock.bind(("127.0.0.1", 9999,)) sock.setblocking(False) sock.listen(128) inputs = [] inputs.append(sock) async_request_dict = { # 'socket': futrue } while True: rlist,wlist,elist = select.select(inputs,[],[],0.05) for r in rlist: if r == sock: """新请求到来""" conn,addr = sock.accept() conn.setblocking(False) inputs.append(conn) else: """客户端发来数据""" data = b"" while True: try: chunk = r.recv(1024) data = data + chunk except Exception as e: chunk = None if not chunk: break # data进行处理：请求头和请求体 request = HttpRequest(data) # 1. 请求头中获取url # 2. 去路由中匹配，获取指定的函数 # 3. 执行函数，获取返回值 # 4. 将返回值 r.sendall(b'alskdjalksdjf;asfd') import re flag = False func = None for route in routers: if re.match(route[0],request.url): flag = True func = route[1] break if flag: result = func(request) if isinstance(result,Future): async_request_dict[r] = result else: r.sendall(bytes(result,encoding='utf-8')) inputs.remove(r) r.close() else: r.sendall(b"404") inputs.remove(r) r.close() for conn in async_request_dict.keys(): future = async_request_dict[conn] start = future.start timeout = future.timeout ctime = time.time() if (start + timeout) <= ctime : future.result = b"timeout" if future.result: conn.sendall(future.result) conn.close() del async_request_dict[conn] inputs.remove(conn) if __name__ == '__main__': run()
