Flask蓝图Blueprint和特殊装饰器
Flask 中的 蓝图 Blueprint
不能被run的flask实例;相当于django中的app01 应用
蓝图作用:功能隔离 路由隔离
Blueprint就是 一个不能run的flask
蓝图的名称app01user 必须保证在app中是唯一
url_prefix 是url前缀;用于隔离相同url
# blueprint.py
from flask import Flask
app = Flask(__name__)
app.debug = True
# 建立蓝图注册 一定要注册
from app01.views import user as app01_user
from app02.views import user as app02_user
app.register_blueprint(app01_user)
app.register_blueprint(app02_user)
if __name__ == '__main__':
app.run()
app01
from flask import Blueprint, render_template
# Blueprint就是 一个不能run的flask
# 蓝图的名称app01user 必须保证在app中是唯一
user = Blueprint("app01user", __name__, template_folder="app01/templates/", url_prefix="/admin") # url_prefix是url前缀;用于隔离相同url
@user.route('/login')
def login():
# return "i am app01 blueprint"
return render_template("login.html")
app02
from flask import Blueprint, render_template
# Blueprint就是 一个不能run的flask
user = Blueprint("app02user", __name__, url_prefix="/shopping") # url_prefix
@user.route('/login')
def login():
return "i am app02 blueprint"
# return render_template('login.html')
蓝图结构
- 项目文件下分别创建manage.py 创建app01目录;
- 在app01目录下分别创建views文件夹、static文件夹、templates文件夹、init.py、models.py
- views 文件夹下创建蓝图 blueprint
# __init__,py
from flask import Flask
from app01.views.blueptrint import user #导入蓝图
def create_app():
app = Flaks(__name__)
app.congig['DEBUG'] = True
# 注册蓝图
app.register_blueprint(user)
# 将app返回
return app
# manage.py
# 导入app 实例
from app01 import create_app
app = create_app()
# 运行
if __name__ = '__main__'
app.run()
# views 下 创建蓝图 blueprint
from flask import Blueprint
# 蓝图实例 user为蓝图名称
user = Blueprint("user" , __name__)
@user.route("/login")
def login():
return "ok 200"
此时就可以运行manage.py文件了;或者Terminal下执行命令 python manage.py运行。
Flask 特殊装饰器
-
@app.before_request 请求进入视图函数之前
-
@app.after_request 请求结束,返回影响客户端之前
正常 be1 - be2 - be3 - vf - af3 - af2 - af1
异常 be1 - be2 - af3 - af2 - af1 -
@app.errorhandler(4xx or 5xx) 重定义错误信息
from flask import Flask, request, session, redirect, render_template
from functools import wraps
app = Flask(__name__)
app.secret_key = "!@#$%^&*()"
USER = {"username": "anwen"}
# def wrapper(func):
# @wraps(func)
# def inner(*args, **kwargs):
# if session.get("user"):
# ret = func(*args, **kwargs)
# return ret
# else:
# return redirect("/login")
#
# return inner
@app.before_request
def be1():
print("be1")
@app.before_request
def be2():
print("be2")
if request.path == "/login":
return None
if session.get("user"):
return None
else:
return redirect("/login")
@app.before_request
def be3():
print("be3")
@app.after_request
def af1(res):
print("af1")
return res
@app.after_request
def af2(res):
print("af2")
return res
@app.after_request
def af3(res):
print("af3")
return res
@app.route('/login', methods=["GET", "POST"])
# @wrapper
def login():
if request.method == 'GET':
return render_template("login.html")
else:
if request.form.get("username") == USER["username"]:
session['user'] = request.form.get("username")
return redirect('/index')
@app.route("/index")
# @wrapper
def index():
print("我是视图函数index")
return render_template("index.html")
@app.route("/index1")
# @wrapper
def index1():
return render_template("index.html")
@app.route("/index2")
# @wrapper
def index2():
return render_template("index.html")
@app.errorhandler(404)
def error404(ErrorMessage):
print(ErrorMessage)
return redirect("https://www.autohome.com.cn/beijing/asdfe32r24rff23r23r")
# return send_file("image/1.jpg")
if __name__ == '__main__':
app.run()