Flask笔记

# -*- coding: utf-8 -*-
from flask import Flask,render_template,request,redirect,session,url_for
import time

app = Flask(__name__,template_folder="templates")
app.secret_key = "A"        #类似于加密盐
app.config["SERVER_NAME"] = "jianping.com"
import functools
def auth(func):

    @functools.wraps(func)     #解决函数名重复的冲突问题
    def inner(*args,**kwargs):
        if not session.get("user_info"):
            return redirect("/login")
        return func(*args,**kwargs)
    print(inner.__name__)
    return inner

@app.route("/index",)
@auth    # index =  auth(index)=inner
def index():
    return render_template("index.html")

@app.route("/text")
@auth
def text():
    return render_template("index.html")

@app.route("/login",methods=["POST","GET"])
def hello_world():
    if request.method == "GET":
        return render_template("login.html")
    else:
        username = request.form.get("username")
        password = request.form.get("password")
        if username == "张建平" and password == "":
            session["user_info"] = "QQ"
            return redirect("/index")
        return render_template("login.html",msg="用户名密码错误")

@app.route("/one",subdomain="zhang")
def one():

    return "草拟大爷"

@app.route("/two",subdomain="cheng")
def two():
    return "草拟妹"

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

flask_one

# -*- coding: utf-8 -*-
from flask import Flask,url_for,views

app = Flask(__name__)

def auth(func):
    def inner(*args,**kwargs):
        result = func(*args,**kwargs)
        print("============会执行")
        return result
    return inner

#函数方法
# @app.route("/index/<int:nid>",endpoint="xx")

def index(nid):
    # url_for("xx",nid=123)
    print(nid)
    return "Index"

app.add_url_rule("/index/<int:nid>",view_func=index,defaults={"nid":444},strict_slashes=False)   #加上默认值不管前端传什么值都默认用后端的，虽然用后端的

#类方法
# class IndexView(views.MethodView):
#     decorators = [auth,]
#     def get(self):
#         v = url_for("index")
#         print(v)
#         return "GET————————"
#     def post(self):
#         return "GET=============="
#
# app.add_url_rule("/index",view_func=IndexView.as_view(name="index"))

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

视图

# -*- coding: utf-8 -*-
from flask import Flask,url_for,request,redirect,render_template,jsonify,make_response
from urllib.parse import urlencode,quote,unquote

app = Flask(__name__)

@app.route("/index",endpoint="xx")
def index():
    get_data = request.args         #get_data:ImmutableMultiDict
    get_dict = get_data.to_dict()   #将上边的结果转换为字典
    get_dict["xx"] = ""           #给字典设置值
    url = urlencode(get_dict)       #浏览器url？后边的地址

    print(request.query_string)     #上边的url，不过是byte类型的
    val = "%E8%8D%89%E6%8B%9F%E5%A4%A7%E7%88%B7"    #url中的中文显示
    print(unquote(val))              #将上边的火星文转换为中文
    res = "好好学习天天向上"
    print(quote(res))                #将中文转换为火星文

    ret = {"name":"alex"}
    print(type(jsonify(ret)))        #<class 'flask.wrappers.Response'>
    # return jsonify(ret)              #返回的结果是json字符串
    response = make_response("<h1>xxxxx</h1>")     #经过make_response处理之后可以有一些功能
    # response.headers["xxx"] = "ooo"
    # print(response)
    return response

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

请求响应

# -*- coding: utf-8 -*-
from flask import Flask,url_for,request,redirect,render_template,jsonify,make_response,Markup
from urllib.parse import urlencode,quote,unquote
app = Flask(__name__)

def text(a1,a2):
    return a1+a2

@app.template_global()    #设置了全局变量及时不用传也可以共享
def sb(a1,a2):
    return a1+a2+100

@app.template_filter()
def db(a1,a2,a3):
    return a1+a2+a3

@app.route("/index",endpoint="xx")
def index():
    v1 = "字符串"
    v2 = [11,22,33]
    v3 = {"k1":"v1","k2":"v2"}
    v4 = Markup("<input type='text' />")
    v5 = "<input type='text' />"            #浏览器显示字符串
    return render_template("index.html",v1=v1,v2=v2,v3=v3,v4=v4,v5=v5,text=text)

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

模板语言

# -*- coding: utf-8 -*-

from flask import Flask,session,Session
from urllib.parse import urlencode,quote,unquote
from werkzeug.local import LocalProxy

app = Flask(__name__)
app.secret_key = "HQ"
app.config["SESSION_COOKIE_NAME"] = "session_key"
"""
'SESSION_COOKIE_NAME':                  'session',
'SESSION_COOKIE_DOMAIN':                None,
'SESSION_COOKIE_PATH':                  None,
'SESSION_COOKIE_HTTPONLY':              True,
'SESSION_COOKIE_SECURE':                False,
'SESSION_REFRESH_EACH_REQUEST':         True,
'PERMANENT_SESSION_LIFETIME':           timedelta(days=31)
"""

@app.route("/index",endpoint="xx")
def index():
    session['xxx'] = 123
    session['xxx1'] = 123
    return "xxx"

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

session

# -*- coding: utf-8 -*-

from flask import Flask,session,Session,flash,get_flashed_messages,redirect,render_template,request
app = Flask(__name__)
app.secret_key = "HQ"

#一个视图函数设置，另一个视图函数取值

@app.route("/users")
def index():
    # msg = request.args.get("msg","")

    msg = session.get("msg")
    print(msg)
    if msg:
        del session["msg"]
    v = get_flashed_messages()
    print(v)
    msg = ""
    return render_template("flash.html",msg=msg)

@app.route("/useradd")
def index_add():
    session["msg"] = "添加成功======="
    flash("添加成功")
    return redirect("/users")

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

闪现

# -*- coding: utf-8 -*-

from flask import Flask
app = Flask(__name__)
app.secret_key = "HQ"

#类似于中间件的操作

@app.before_request
def process_request1():
    print("process_request1===================1")

@app.after_request
def process_response1(response):
    print("process_response1==================1")
    return response

@app.before_request
def process_request2():
    print("process_request2====================2")

@app.after_request
def process_response2(response):
    print("process_response2===================2")
    return response

@app.route("/index")
def index():
    print("index")
    return "INDEX"

@app.route("/order")
def order():
    print("order")
    return "ORDER"

@app.route("/text")
def text():
    print("text")
    return "TExT"

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

扩展

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

<h1>{{msg}}</h1>

<h1>welcome to my index</h1>

<hr>
v1:{{v1}}
v2:{{v2}}
v3:{{v3}}
v4:{{v4}}
v5:{{v5}}
text{{text(1,2)}}
<br>
<hr>
<!--可循环-->
{% for item in v2 %}
    v2:{{item}}
{% endfor %}
<hr>
<!--字典可循环-->
{% for k,v in v3.items() %}
{{k}},{{v}}
{% endfor %}
<br>
{{v3.k1}}
{{v3.get("k1")}}

<hr>

{{sb(1,2)}}

<br>
{{1|db(2,3)}}
<hr>

<!--类似于for循环-->
{% macro xxxx(name,type='text',value='') %}
    <input type="{{ type }}" name="{{ name }}" value="{{ value }}" >
    <input type="{{ type }}" name="{{ name }}" value="{{ value }}" >
    <input type="{{ type }}" name="{{ name }}" value="{{ value }}" >
{% endmacro %}

{{ xxxx("zhang")}}

<hr>

<img src="/static/school.png" alt="">

</body>
</html>

index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<h1>欢迎访问</h1>
<form method="post">
    <input type="text" name="username">
    <input type="text" name="password">
    <input type="submit">
    {{msg}}
</form>
</body>
</html>

login.html

测试页面

# -*- coding: utf-8 -*-
from flask import Flask,url_for
app = Flask(__name__)

from werkzeug.routing import BaseConverter

class RegexConverter(BaseConverter):
    """
    自定义URL匹配正则表达式
    """

    def __init__(self, map, regex):
        super(RegexConverter, self).__init__(map)
        self.regex = regex

    def to_python(self, value):
        """
        路由匹配时，匹配成功后传递给视图函数中参数的值
        :param value:
        :return:
        """
        return int(value)

    def to_url(self, value):
        """
        使用url_for反向生成URL时，传递的参数经过该方法处理，返回的值用于生成URL中的参数
        :param value:
        :return:
        """
        val = super(RegexConverter, self).to_url(value)
        return val

app.url_map.converters["xxx"] = RegexConverter

@app.route("/index/<xxx('\d+'):nid>",endpoint="xx")
def index(nid):
    url_for("xx",nid=123)
    return "Index"

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

正则表达式　

前端参数传递：
{#前端url传参 {{ url_for('index',qq=7) }}#}
闪现是基于session实现的，先设置，然后删除，闪现，顾名思义，只是出现一次就消失了，flash设置值；
get_flashed_messages获取值（只能获取一次，第二次获取不到任何东西）