由于公司使用了Tornado框架和Flask框架,之前一直使用的都是Flask框架,已经对url下面紧跟着视图的写法很固执。刚开始接触Tornado框架,对于其url和视图分开的写法思想上无法转变。今天看了Flask的源码和相关教程看到原来 Flask也可以写出和Tornado类似的代码结构--Flask即插视图。
代码如下:
from functools import wraps
from flask import Flask, request
from flask.views import MethodView
app = Flask(__name__)
# get请求装饰器
def decorator_func_get(f):
@wraps(f)
def write(*args, **kwargs):
print(request.method, 'decorator_func_get')
print('You can add some decorator before request into view function!')
return f(*args, **kwargs)
return write
# post请求装饰器
def decorator_func_post(f):
@wraps(f)
def write(*args, **kwargs):
print(request.method, 'decorator_func_post')
print('You can add some decorator before request into view function!')
return f(*args, **kwargs)
return write
# 公用装饰器
def decorator_func_all(f):
@wraps(f)
def write(*args, **kwargs):
print(request.method, 'decorator_func_all')
print('You can add some decorator before request into view function!')
return f(*args, **kwargs)
return write
class User(MethodView):
# 所以http方法进入后都要使用的装饰器
decorators = [decorator_func_all]
# 只针对get请求的装饰器
@decorator_func_get
def get(self, user_id):
return f'get uid:{user_id}'
# 只针对post请求的装饰器
@decorator_func_post
def post(self):
uid = request.form.get('user_id')
return f'create a user {uid}'
def delete(self, user_id):
return f'delete a uid:{user_id}'
def put(self, user_id):
return f'update a uid:{user_id}'
# 可以重构一个路由注册函数,可以更加方便
user_view = User.as_view('user_api') # 'user_api'为endpoint
app.add_url_rule('/users', defaults={'user_id': None}, view_func=user_view, methods=['GET']) # url:/users,GET
app.add_url_rule('/users', view_func=user_view, methods=['POST']) # url:users,POST
app.add_url_rule('/users/<int:user_id>', view_func=user_view, methods=['GET', 'PUT', 'DELETE']) # url:users,POST
app.run(host='127.0.0.1', port=8000, debug=True)
其实对于即插视图的add_url_rule()方法和如下的route()方法都是一样的,因为源码中,route()调用的就是add_url_rule()方法。
代码段:1
@app.route('/', methods=['GET', 'POST'])
@some_decorator
def index():
data = {
'msg': 'API SERVER IS RUNNING~',
'version': version,
}
data.update(get_version_ctrl())
return msg(data)
即插视图优点:
if request.method=='GET':
print('do some get method things')
else:
print('do some other method things')
Tornado框架简单程序(主要体现其注册视图函数的方法和flask的即插视图很像):
import torndb
import tornado.web
import tornado.ioloop
from tornado.options import define,options,parse_command_line
define('port',default=8888,help='run on the port',type=int)
database=torndb.Connection('localhost','talk',user='root',password='ll')
l=[]
class MainHandler(tornado.web.RequestHandler):
def get(self):
self.render('a.html',title='haha',items=l)
def post(self):
count=1
print(self.request.remote_ip)
talk=self.get_argument('talk')
talk=str(talk)
database.execute('insert into chatting(id,content) values(%d,"%s")'%(count,talk))
l.append(talk)
self.render('a.html',title='haha',items=l)
def main():
parse_command_line()
app=tornado.web.Application(
[
(r'/',MainHandler),
],
)
app.listen(options.port)
tornado.ioloop.IOLoop.instance().start()
if __name__=='__main__':
main()