tornado系列四:web请求
1、同步请求
import tornado.httpserver
import tornado.ioloop
import tornado.options
import tornado.web
import tornado.httpclient
import urllib
import json
import datetime
import time
from tornado.options import define, options
define("port", default=8000, help="run on the given port", type=int)
class IndexHandler(tornado.web.RequestHandler):
def get(self):
query = self.get_argument('q')
client = tornado.httpclient.HTTPClient()
response = client.fetch("http://search.twitter.com/search.json?" + \ urllib.urlencode({"q": query, "result_type": "recent", "rpp": 100})) body = json.loads(response.body)
result_count = len(body['results'])
now = datetime.datetime.utcnow()
raw_oldest_tweet_at = body['results'][-1]['created_at']
oldest_tweet_at = datetime.datetime.strptime(raw_oldest_tweet_at,
"%a, %d %b %Y %H:%M:%S +0000")
seconds_diff = time.mktime(now.timetuple()) - \
time.mktime(oldest_tweet_at.timetuple())
tweets_per_second = float(result_count) / seconds_diff
self.write("""
<div style="text-align: center">
<div style="font-size: 72px">%s</div>
<div style="font-size: 144px">%.02f</div>
<div style="font-size: 24px">tweets per second</div>
</div>""" % (query, tweets_per_second))
if __name__ == "__main__":
tornado.options.parse_command_line()
app = tornado.web.Application(handlers=[(r"/", IndexHandler)])
http_server = tornado.httpserver.HTTPServer(app)
http_server.listen(options.port)
tornado.ioloop.IOLoop.instance().start()
2、使用回调函数的异步请求
import tornado.httpserver
import tornado.ioloop
import tornado.options
import tornado.web
import tornado.httpclient
import urllib
import json
import datetime
import time
from tornado.options import define, options
define("port", default=8000, help="run on the given port", type=int)
class IndexHandler(tornado.web.RequestHandler):
@tornado.web.asynchronous #保证在函数返回后，连接不立即关闭，待异步处理完毕后手动关闭连接
def get(self):
query = self.get_argument('q')
client = tornado.httpclient.AsyncHTTPClient() client.fetch("http://search.twitter.com/search.json?" + \ urllib.urlencode({"q": query, "result_type": "recent", "rpp": 100}), callback=self.on_response) #设置response返回后的回调函数
def on_response(self, response):
body = json.loads(response.body)
result_count = len(body['results'])
now = datetime.datetime.utcnow()
raw_oldest_tweet_at = body['results'][-1]['created_at']
oldest_tweet_at = datetime.datetime.strptime(raw_oldest_tweet_at,
"%a, %d %b %Y %H:%M:%S +0000")
seconds_diff = time.mktime(now.timetuple()) - \
time.mktime(oldest_tweet_at.timetuple())
tweets_per_second = float(result_count) / seconds_diff
self.write("""
<div style="text-align: center">
<div style="font-size: 72px">%s</div>
<div style="font-size: 144px">%.02f</div>
<div style="font-size: 24px">tweets per second</div>
</div>""" % (self.get_argument('q'), tweets_per_second))
self.finish() #手动关闭连接
if __name__ == "__main__":
tornado.options.parse_command_line()
app = tornado.web.Application(handlers=[(r"/", IndexHandler)])
http_server = tornado.httpserver.HTTPServer(app)
http_server.listen(options.port)
tornado.ioloop.IOLoop.instance().start()
3、采用异步生成器方式的异步请求
import tornado.httpserver
import tornado.ioloop
import tornado.options
import tornado.web
import tornado.httpclient import tornado.gen
import urllib
import json
import datetime
import time
from tornado.options import define, options
define("port", default=8000, help="run on the given port", type=int)
class IndexHandler(tornado.web.RequestHandler):
@tornado.web.asynchronous @tornado.gen.engine
def get(self):
query = self.get_argument('q')
client = tornado.httpclient.AsyncHTTPClient() response = yield tornado.gen.Task(client.fetch, "http://search.twitter.com/search.json?" + \ urllib.urlencode({"q": query, "result_type": "recent", "rpp": 100}))
body = json.loads(response.body)
result_count = len(body['results'])
now = datetime.datetime.utcnow()
raw_oldest_tweet_at = body['results'][-1]['created_at']
oldest_tweet_at = datetime.datetime.strptime(raw_oldest_tweet_at,
"%a, %d %b %Y %H:%M:%S +0000")
seconds_diff = time.mktime(now.timetuple()) - \
time.mktime(oldest_tweet_at.timetuple())
tweets_per_second = float(result_count) / seconds_diff
self.write("""
<div style="text-align: center">
<div style="font-size: 72px">%s</div>
<div style="font-size: 144px">%.02f</div>
<div style="font-size: 24px">tweets per second</div>
</div>""" % (query, tweets_per_second))
self.finish()
if __name__ == "__main__":
tornado.options.parse_command_line()
app = tornado.web.Application(handlers=[(r"/", IndexHandler)])
http_server = tornado.httpserver.HTTPServer(app)
http_server.listen(options.port)
tornado.ioloop.IOLoop.instance().start()