Flask基础-基础实例

1. 10行代码的迷你程序 flask项目

from flask import  Flask

app = Flask(__name__)


@app.route("/index")
def inde():
    return "heeello world"

if __name__ =="__main__":
    app.run()

2.页面登录的小程序+session简单用法.

from flask import  Flask,render_template,request,redirect,session

app = Flask(__name__)
app.secret_key="dd"

@app.route("/login",methods =["GET","POST"])
def login():
    if request.method =='GET':

        return render_template("login.html")

    #request.form为post请求
    user =request.form.get("user")
    pwd =request.form.get("pwd")
    if user =="hailong" and pwd =="kuang":

        #设置session , flask的session存放在cookie当中
        session["user_infor"]=user
        print(22)
        return redirect("/index")
    print(111)
    return  render_template("login.htm",msg ="用户密码错误")

@app.route("/index")
def index():
    
    #获取cookie 判断是否存在,如果存在并匹配进行跳转到相关页面
    user_infor =session.get("user_infor")
    print(222,user_infor)
    if not user_infor:
        return redirect("/login")
    return render_template("index.html")

if __name__ =="__main__":
    app.run()

login页面

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>login</title>

</head>
</head>
<body>
    <h1>     用户登录</h1>
<form method="post">
    <input type="text" name ="user">
    <input type="password" name ="pwd">
    <input type="submit" value="提交">{{msg}}

</form>
</body>
</html>

index界面

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
        <h1>欢迎来到郝龙江家里</h1>
</body>
</html>

3 .auth认证.

 1 from flask import Flask,render_template,request,redirect,session
 2 
 3 app = Flask(__name__)
 4 
 5 app.secret_key = '39jrlasdfoajslfu8af'
 6 
 7 
 8 import functools
 9 
10 def auth(func):
11     @functools.wraps(func) # 保留函数的元信息
12     def inner(*args,**kwargs):
13         if not session.get('user_info'):
14             return redirect('/login')
15         ret = func(*args,**kwargs)
16         return ret
17     return inner
18 
19 
20 @app.route('/login',methods=['GET','POST'])
21 def login():
22     if request.method == 'GET':
23         return render_template('login.html')
24 
25     user = request.form.get('user')
26     pwd = request.form.get('pwd')
27     if user == 'hailong' and pwd == 'kuang':
28         session['user_info'] = user
29         return redirect('/index')
30     return render_template('login.html',msg="用户名或密码错误")
31 
32 
33 @app.route('/index')
34 @auth
35 def index():
36     kuang_list = [
37         {'id':1,'name':'一矿','address':'大同'},
38         {'id':2,'name':'二矿','address':'大同'},
39         {'id':3,'name':'三矿','address':'大同'},
40     ]
41 
42     return render_template('index.html',klist=kuang_list)
43     # return render_template('index.html',**{'klist':kuang_list})
44 
45 @app.route('/detail')
46 @auth
47 def detail():
48     nid = request.args.get('nid')
49     return render_template('detail.html')
50 
51 
52 @app.route('/logout')
53 def logout():
54     del session['user_info']
55 
56     return redirect('/login')
57 
58 if __name__ == '__main__':
59     app.run()

4.中间件

 1 from flask import Flask,render_template,request,redirect,session
 2 
 3 app = Flask(__name__)
 4 
 5 app.secret_key = '39jrlasdfoajslfu8af'
 6 
 7 
 8 @app.before_request
 9 def xxxxxxxxxxxxxx():
10     if request.path == '/login':
11         return None
12 
13     if not session.get('user_info'):
14         return redirect('/login')
15 
16 
17 @app.route('/login',methods=['GET','POST'])
18 def login():
19     print('我是login')
20     if request.method == 'GET':
21         return render_template('login.html')
22 
23     user = request.form.get('user')
24     pwd = request.form.get('pwd')
25     if user == 'hailong' and pwd == 'kuang':
26         session['user_info'] = user
27         return redirect('/index')
28     return render_template('login.html',msg="用户名或密码错误")
29 
30 
31 @app.route('/index')
32 def index():
33     print('我是index')
34     kuang_list = [
35         {'id':1,'name':'一矿','address':'大同'},
36         {'id':2,'name':'二矿','address':'大同'},
37         {'id':3,'name':'三矿','address':'大同'},
38     ]
39 
40     return render_template('index.html',klist=kuang_list)
41     # return render_template('index.html',**{'klist':kuang_list})
42 
43 @app.route('/detail')
44 def detail():
45     nid = request.args.get('nid')
46     return render_template('detail.html')
47 
48 
49 @app.route('/logout')
50 def logout():
51     del session['user_info']
52 
53     return redirect('/login')
54 
55 if __name__ == '__main__':
56     app.run()