Flask Oldboy s4 Flask

Oldboy s4 Flask

Flask是一个基于Python开发并且依赖jinja2模板和Werkzeug WSGI服务的一个微型框架,对于Werkzeug本质是Socket服务端,其用于接收http请求并对请求进行预处理,然后触发Flask框架,开发人员基于Flask框架提供的功能对请求进行相应的处理,并返回给用户,如果要返回给用户复杂的内容时,需要借助jinja2模板来实现对模板的处理,即:将模板和数据进行渲染,将渲染后的字符串返回给用户浏览器。

“微”(micro) 并不表示你需要把整个 Web 应用塞进单个 Python 文件(虽然确实可以 ),也不意味着 Flask 在功能上有所欠缺。微框架中的“微”意味着 Flask 旨在保持核心简单而易于扩展。Flask 不会替你做出太多决策——比如使用何种数据库。而那些 Flask 所选择的——比如使用何种模板引擎——则很容易替换。除此之外的一切都由可由你掌握。如此,Flask 可以与您珠联璧合。

默认情况下,Flask 不包含数据库抽象层、表单验证,或是其它任何已有多种库可以胜任的功能。然而,Flask 支持用扩展来给应用添加这些功能,如同是 Flask 本身实现的一样。众多的扩展提供了数据库集成、表单验证、上传处理、各种各样的开放认证技术等功能。Flask 也许是“微小”的,但它已准备好在需求繁杂的生产环境中投入使用。

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pip3 install flask
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from werkzeug.wrappers import Request, Response

@Request.application
def hello(request):
    return Response('Hello World!') if __name__ == '__main__': from werkzeug.serving import run_simple run_simple('localhost', 4000, hello)
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一. 基本使用

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from flask import Flask
app = Flask(__name__)
 
@app .route( '/' )
def hello_world():
     return 'Hello World!'
 
if __name__ = = '__main__' :
     app.run()

二、配置文件

三、路由系统

  • @app.route('/user/<username>')
  • @app.route('/post/<int:post_id>')
  • @app.route('/post/<float:post_id>')
  • @app.route('/post/<path:path>')
  • @app.route('/login', methods=['GET', 'POST'])

常用路由系统有以上五种,所有的路由系统都是基于一下对应关系来处理:

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DEFAULT_CONVERTERS = {
     'default' :          UnicodeConverter,
     'string' :           UnicodeConverter,
     'any' :              AnyConverter,
     'path' :             PathConverter,
     'int' :              IntegerConverter,
     'float' :            FloatConverter,
     'uuid' :             UUIDConverter,
}
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        def auth(func):
            def inner(*args, **kwargs):
                print('before') result = func(*args, **kwargs) print('after') return result return inner @app.route('/index.html',methods=['GET','POST'],endpoint='index') @auth def index(): return 'Index'def index(): return "Index" self.add_url_rule(rule='/index.html', endpoint="index", view_func=index, methods=["GET","POST"]) or app.add_url_rule(rule='/index.html', endpoint="index", view_func=index, methods=["GET","POST"]) app.view_functions['index'] = index 或 def auth(func): def inner(*args, **kwargs): print('before') result = func(*args, **kwargs) print('after') return result return inner class IndexView(views.View): methods = ['GET'] decorators = [auth, ] def dispatch_request(self): print('Index') return 'Index!' app.add_url_rule('/index', view_func=IndexView.as_view(name='index')) # name=endpoint class IndexView(views.MethodView): methods = ['GET'] decorators = [auth, ] def get(self): return 'Index.GET' def post(self): return 'Index.POST' app.add_url_rule('/index', view_func=IndexView.as_view(name='index')) # name=endpoint  @app.route和app.add_url_rule参数: rule, URL规则 view_func, 视图函数名称 defaults=None, 默认值,当URL中无参数,函数需要参数时,使用defaults={'k':'v'}为函数提供参数 endpoint=None, 名称,用于反向生成URL,即: url_for('名称') methods=None, 允许的请求方式,如:["GET","POST"] strict_slashes=None, 对URL最后的 / 符号是否严格要求, 如: @app.route('/index',strict_slashes=False), 访问 http://www.xx.com/index/ 或 http://www.xx.com/index均可 @app.route('/index',strict_slashes=True) 仅访问 http://www.xx.com/index redirect_to=None, 重定向到指定地址 如: @app.route('/index/<int:nid>', redirect_to='/home/<nid>') 或 def func(adapter, nid): return "/home/888" @app.route('/index/<int:nid>', redirect_to=func) subdomain=None, 子域名访问 from flask import Flask, views, url_for app = Flask(import_name=__name__) app.config['SERVER_NAME'] = 'wupeiqi.com:5000' @app.route("/", subdomain="admin") def static_index(): """Flask supports static subdomains This is available at static.your-domain.tld""" return "static.your-domain.tld" @app.route("/dynamic", subdomain="<username>") def username_index(username): """Dynamic subdomains are also supported Try going to user1.your-domain.tld/dynamic""" return username + ".your-domain.tld" if __name__ == '__main__': app.run() 
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           from flask import Flask, views, url_for
            from werkzeug.routing import BaseConverter app = Flask(import_name=__name__) 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 # 添加到flask中 app.url_map.converters['regex'] = RegexConverter @app.route('/index/<regex("\d+"):nid>') def index(nid): print(url_for('index', nid='888')) return 'Index' if __name__ == '__main__': app.run()
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四、模板

1、模板的使用

Flask使用的是Jinja2模板,所以其语法和Django无差别

2、自定义模板方法

Flask中自定义模板方法的方式和Bottle相似,创建一个函数并通过参数的形式传入render_template,如:

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<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8"> <title></title> </head> <body> <h1>自定义函数</h1> {{ww()|safe}} </body> </html>
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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from flask import Flask,render_template app = Flask(__name__) def wupeiqi(): return '<h1>Wupeiqi</h1>' @app.route('/login', methods=['GET', 'POST']) def login(): return render_template('login.html', ww=wupeiqi) app.run()
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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8"> <title>Title</title> </head> <body> {% macro input(name, type='text', value='') %} <input type="{{ type }}" name="{{ name }}" value="{{ value }}"> {% endmacro %} {{ input('n1') }} {% include 'tp.html' %} <h1>asdf{{ v.k1}}</h1> </body> </html>
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注意:Markup等价django的mark_safe

五、请求和响应

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   from flask import Flask
    from flask import request from flask import render_template from flask import redirect from flask import make_response app = Flask(__name__) @app.route('/login.html', methods=['GET', "POST"]) def login(): # 请求相关信息 # request.method # request.args # request.form # request.values # request.cookies # request.headers # request.path # request.full_path # request.script_root # request.url # request.base_url # request.url_root # request.host_url # request.host # request.files # obj = request.files['the_file_name'] # obj.save('/var/www/uploads/' + secure_filename(f.filename)) # 响应相关信息 # return "字符串" # return render_template('html模板路径',**{}) # return redirect('/index.html') # response = make_response(render_template('index.html')) # response是flask.wrappers.Response类型 # response.delete_cookie('key') # response.set_cookie('key', 'value') # response.headers['X-Something'] = 'A value' # return response return "内容" if __name__ == '__main__': app.run()
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六、Session

除请求对象之外,还有一个 session 对象。它允许你在不同请求间存储特定用户的信息。它是在 Cookies 的基础上实现的,并且对 Cookies 进行密钥签名要使用会话,你需要设置一个密钥。

  • 设置:session['username'] = 'xxx'

  • 删除:session.pop('username', None)
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from flask import Flask, session, redirect, url_for, escape, request
 
app = Flask(__name__)
 
@app.route('/') def index(): if 'username' in session: return 'Logged in as %s' % escape(session['username']) return 'You are not logged in' @app.route('/login', methods=['GET', 'POST']) def login(): if request.method == 'POST': session['username'] = request.form['username'] return redirect(url_for('index')) return ''' <form action="" method="post"> <p><input type=text name=username> <p><input type=submit value=Login> </form> ''' @app.route('/logout') def logout(): # remove the username from the session if it's there session.pop('username', None) return redirect(url_for('index')) # set the secret key. keep this really secret: app.secret_key = 'A0Zr98j/3yX R~XHH!jmN]LWX/,?RT'
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        pip3 install Flask-Session
        
        run.py
            from flask import Flask
            from flask import session from pro_flask.utils.session import MySessionInterface app = Flask(__name__) app.secret_key = 'A0Zr98j/3yX R~XHH!jmN]LWX/,?RT' app.session_interface = MySessionInterface() @app.route('/login.html', methods=['GET', "POST"]) def login(): print(session) session['user1'] = 'alex' session['user2'] = 'alex' del session['user2'] return "内容" if __name__ == '__main__': app.run() session.py #!/usr/bin/env python # -*- coding:utf-8 -*- import uuid import json from flask.sessions import SessionInterface from flask.sessions import SessionMixin from itsdangerous import Signer, BadSignature, want_bytes class MySession(dict, SessionMixin): def __init__(self, initial=None, sid=None): self.sid = sid self.initial = initial super(MySession, self).__init__(initial or ()) def __setitem__(self, key, value): super(MySession, self).__setitem__(key, value) def __getitem__(self, item): return super(MySession, self).__getitem__(item) def __delitem__(self, key): super(MySession, self).__delitem__(key) class MySessionInterface(SessionInterface): session_class = MySession container = {} def __init__(self): import redis self.redis = redis.Redis() def _generate_sid(self): return str(uuid.uuid4()) def _get_signer(self, app): if not app.secret_key: return None return Signer(app.secret_key, salt='flask-session', key_derivation='hmac') def open_session(self, app, request): """ 程序刚启动时执行,需要返回一个session对象 """ sid = request.cookies.get(app.session_cookie_name) if not sid: sid = self._generate_sid() return self.session_class(sid=sid) signer = self._get_signer(app) try: sid_as_bytes = signer.unsign(sid) sid = sid_as_bytes.decode() except BadSignature: sid = self._generate_sid() return self.session_class(sid=sid) # session保存在redis中 # val = self.redis.get(sid) # session保存在内存中 val = self.container.get(sid) if val is not None: try: data = json.loads(val) return self.session_class(data, sid=sid) except: return self.session_class(sid=sid) return self.session_class(sid=sid) def save_session(self, app, session, response): """ 程序结束前执行,可以保存session中所有的值 如: 保存到resit 写入到用户cookie """ domain = self.get_cookie_domain(app) path = self.get_cookie_path(app) httponly = self.get_cookie_httponly(app) secure = self.get_cookie_secure(app) expires = self.get_expiration_time(app, session) val = json.dumps(dict(session)) # session保存在redis中 # self.redis.setex(name=session.sid, value=val, time=app.permanent_session_lifetime) # session保存在内存中  self.container.setdefault(session.sid, val) session_id = self._get_signer(app).sign(want_bytes(session.sid)) response.set_cookie(app.session_cookie_name, session_id, expires=expires, httponly=httponly, domain=domain, path=path, secure=secure)
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#!/usr/bin/env python
# -*- coding:utf-8 -*-
""" pip3 install redis pip3 install flask-session """ from flask import Flask, session, redirect from flask.ext.session import Session app = Flask(__name__) app.debug = True app.secret_key = 'asdfasdfasd' app.config['SESSION_TYPE'] = 'redis' from redis import Redis app.config['SESSION_REDIS'] = Redis(host='192.168.0.94',port='6379') Session(app) @app.route('/login') def login(): session['username'] = 'alex' return redirect('/index') @app.route('/index') def index(): name = session['username'] return name if __name__ == '__main__': app.run()
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七、蓝图

蓝图用于为应用提供目录划分:

小型应用程序:示例

大型应用程序:示例

其他:

  • 蓝图URL前缀:xxx = Blueprint('account', __name__,url_prefix='/xxx')
  • 蓝图子域名:xxx = Blueprint('account', __name__,subdomain='admin')
    # 前提需要给配置SERVER_NAME: app.config['SERVER_NAME'] = 'wupeiqi.com:5000'
    # 访问时:admin.wupeiqi.com:5000/login.html

八、message

message是一个基于Session实现的用于保存数据的集合,其特点是:使用一次就删除。

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        from flask import Flask, flash, redirect, render_template, request, get_flashed_messages

        app = Flask(__name__)
        app.secret_key = 'some_secret' @app.route('/') def index1(): messages = get_flashed_messages() print(messages) return "Index1" @app.route('/set') def index2(): v = request.args.get('p') flash(v) return 'ok' if __name__ == "__main__": app.run()
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九、中间件

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from flask import Flask, flash, redirect, render_template, request
 
app = Flask(__name__)
app.secret_key = 'some_secret' @app.route('/') def index1(): return render_template('index.html') @app.route('/set') def index2(): v = request.args.get('p') flash(v) return 'ok' class MiddleWare: def __init__(self,wsgi_app): self.wsgi_app = wsgi_app def __call__(self, *args, **kwargs): return self.wsgi_app(*args, **kwargs) if __name__ == "__main__": app.wsgi_app = MiddleWare(app.wsgi_app) app.run(port=9999)
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十、请求扩展

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from flask import Flask, Request, render_template app = Flask(__name__, template_folder='templates') app.debug = True @app.before_first_request def before_first_request1(): print('before_first_request1') @app.before_first_request def before_first_request2(): print('before_first_request2') @app.before_request def before_request1(): Request.nnn = 123 print('before_request1') @app.before_request def before_request2(): print('before_request2') @app.after_request def after_request1(response): print('before_request1', response) return response @app.after_request def after_request2(response): print('before_request2', response) return response @app.errorhandler(404) def page_not_found(error): return 'This page does not exist', 404 @app.template_global() def sb(a1, a2): return a1 + a2 @app.template_filter() def db(a1, a2, a3): return a1 + a2 + a3 @app.route('/') def hello_world(): return render_template('hello.html') if __name__ == '__main__': app.run()
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调用方式:{{sb(1,2)}}  {{ 1|db(2,3)}}

十一、Flask插件

  • WTForms    
  • SQLAchemy
  • 等...    http://flask.pocoo.org/extensions/

Flask是一个基于Python开发并且依赖jinja2模板和Werkzeug WSGI服务的一个微型框架,对于Werkzeug本质是Socket服务端,其用于接收http请求并对请求进行预处理,然后触发Flask框架,开发人员基于Flask框架提供的功能对请求进行相应的处理,并返回给用户,如果要返回给用户复杂的内容时,需要借助jinja2模板来实现对模板的处理,即:将模板和数据进行渲染,将渲染后的字符串返回给用户浏览器。

“微”(micro) 并不表示你需要把整个 Web 应用塞进单个 Python 文件(虽然确实可以 ),也不意味着 Flask 在功能上有所欠缺。微框架中的“微”意味着 Flask 旨在保持核心简单而易于扩展。Flask 不会替你做出太多决策——比如使用何种数据库。而那些 Flask 所选择的——比如使用何种模板引擎——则很容易替换。除此之外的一切都由可由你掌握。如此,Flask 可以与您珠联璧合。

默认情况下,Flask 不包含数据库抽象层、表单验证,或是其它任何已有多种库可以胜任的功能。然而,Flask 支持用扩展来给应用添加这些功能,如同是 Flask 本身实现的一样。众多的扩展提供了数据库集成、表单验证、上传处理、各种各样的开放认证技术等功能。Flask 也许是“微小”的,但它已准备好在需求繁杂的生产环境中投入使用。

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pip3 install flask
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from werkzeug.wrappers import Request, Response

@Request.application
def hello(request):
    return Response('Hello World!') if __name__ == '__main__': from werkzeug.serving import run_simple run_simple('localhost', 4000, hello)
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一. 基本使用

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from flask import Flask
app = Flask(__name__)
 
@app .route( '/' )
def hello_world():
     return 'Hello World!'
 
if __name__ = = '__main__' :
     app.run()

二、配置文件

三、路由系统

  • @app.route('/user/<username>')
  • @app.route('/post/<int:post_id>')
  • @app.route('/post/<float:post_id>')
  • @app.route('/post/<path:path>')
  • @app.route('/login', methods=['GET', 'POST'])

常用路由系统有以上五种,所有的路由系统都是基于一下对应关系来处理:

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DEFAULT_CONVERTERS = {
     'default' :          UnicodeConverter,
     'string' :           UnicodeConverter,
     'any' :              AnyConverter,
     'path' :             PathConverter,
     'int' :              IntegerConverter,
     'float' :            FloatConverter,
     'uuid' :             UUIDConverter,
}
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        def auth(func):
            def inner(*args, **kwargs):
                print('before') result = func(*args, **kwargs) print('after') return result return inner @app.route('/index.html',methods=['GET','POST'],endpoint='index') @auth def index(): return 'Index'def index(): return "Index" self.add_url_rule(rule='/index.html', endpoint="index", view_func=index, methods=["GET","POST"]) or app.add_url_rule(rule='/index.html', endpoint="index", view_func=index, methods=["GET","POST"]) app.view_functions['index'] = index 或 def auth(func): def inner(*args, **kwargs): print('before') result = func(*args, **kwargs) print('after') return result return inner class IndexView(views.View): methods = ['GET'] decorators = [auth, ] def dispatch_request(self): print('Index') return 'Index!' app.add_url_rule('/index', view_func=IndexView.as_view(name='index')) # name=endpoint class IndexView(views.MethodView): methods = ['GET'] decorators = [auth, ] def get(self): return 'Index.GET' def post(self): return 'Index.POST' app.add_url_rule('/index', view_func=IndexView.as_view(name='index')) # name=endpoint  @app.route和app.add_url_rule参数: rule, URL规则 view_func, 视图函数名称 defaults=None, 默认值,当URL中无参数,函数需要参数时,使用defaults={'k':'v'}为函数提供参数 endpoint=None, 名称,用于反向生成URL,即: url_for('名称') methods=None, 允许的请求方式,如:["GET","POST"] strict_slashes=None, 对URL最后的 / 符号是否严格要求, 如: @app.route('/index',strict_slashes=False), 访问 http://www.xx.com/index/ 或 http://www.xx.com/index均可 @app.route('/index',strict_slashes=True) 仅访问 http://www.xx.com/index redirect_to=None, 重定向到指定地址 如: @app.route('/index/<int:nid>', redirect_to='/home/<nid>') 或 def func(adapter, nid): return "/home/888" @app.route('/index/<int:nid>', redirect_to=func) subdomain=None, 子域名访问 from flask import Flask, views, url_for app = Flask(import_name=__name__) app.config['SERVER_NAME'] = 'wupeiqi.com:5000' @app.route("/", subdomain="admin") def static_index(): """Flask supports static subdomains This is available at static.your-domain.tld""" return "static.your-domain.tld" @app.route("/dynamic", subdomain="<username>") def username_index(username): """Dynamic subdomains are also supported Try going to user1.your-domain.tld/dynamic""" return username + ".your-domain.tld" if __name__ == '__main__': app.run() 
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           from flask import Flask, views, url_for
            from werkzeug.routing import BaseConverter app = Flask(import_name=__name__) 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 # 添加到flask中 app.url_map.converters['regex'] = RegexConverter @app.route('/index/<regex("\d+"):nid>') def index(nid): print(url_for('index', nid='888')) return 'Index' if __name__ == '__main__': app.run()
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四、模板

1、模板的使用

Flask使用的是Jinja2模板,所以其语法和Django无差别

2、自定义模板方法

Flask中自定义模板方法的方式和Bottle相似,创建一个函数并通过参数的形式传入render_template,如:

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<!DOCTYPE html>
<html>
<head lang="en">
    <meta charset="UTF-8"> <title></title> </head> <body> <h1>自定义函数</h1> {{ww()|safe}} </body> </html>
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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from flask import Flask,render_template app = Flask(__name__) def wupeiqi(): return '<h1>Wupeiqi</h1>' @app.route('/login', methods=['GET', 'POST']) def login(): return render_template('login.html', ww=wupeiqi) app.run()
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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8"> <title>Title</title> </head> <body> {% macro input(name, type='text', value='') %} <input type="{{ type }}" name="{{ name }}" value="{{ value }}"> {% endmacro %} {{ input('n1') }} {% include 'tp.html' %} <h1>asdf{{ v.k1}}</h1> </body> </html>
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注意:Markup等价django的mark_safe

五、请求和响应

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   from flask import Flask
    from flask import request from flask import render_template from flask import redirect from flask import make_response app = Flask(__name__) @app.route('/login.html', methods=['GET', "POST"]) def login(): # 请求相关信息 # request.method # request.args # request.form # request.values # request.cookies # request.headers # request.path # request.full_path # request.script_root # request.url # request.base_url # request.url_root # request.host_url # request.host # request.files # obj = request.files['the_file_name'] # obj.save('/var/www/uploads/' + secure_filename(f.filename)) # 响应相关信息 # return "字符串" # return render_template('html模板路径',**{}) # return redirect('/index.html') # response = make_response(render_template('index.html')) # response是flask.wrappers.Response类型 # response.delete_cookie('key') # response.set_cookie('key', 'value') # response.headers['X-Something'] = 'A value' # return response return "内容" if __name__ == '__main__': app.run()
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六、Session

除请求对象之外,还有一个 session 对象。它允许你在不同请求间存储特定用户的信息。它是在 Cookies 的基础上实现的,并且对 Cookies 进行密钥签名要使用会话,你需要设置一个密钥。

  • 设置:session['username'] = 'xxx'

  • 删除:session.pop('username', None)
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from flask import Flask, session, redirect, url_for, escape, request
 
app = Flask(__name__)
 
@app.route('/') def index(): if 'username' in session: return 'Logged in as %s' % escape(session['username']) return 'You are not logged in' @app.route('/login', methods=['GET', 'POST']) def login(): if request.method == 'POST': session['username'] = request.form['username'] return redirect(url_for('index')) return ''' <form action="" method="post"> <p><input type=text name=username> <p><input type=submit value=Login> </form> ''' @app.route('/logout') def logout(): # remove the username from the session if it's there session.pop('username', None) return redirect(url_for('index')) # set the secret key. keep this really secret: app.secret_key = 'A0Zr98j/3yX R~XHH!jmN]LWX/,?RT'
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        pip3 install Flask-Session
        
        run.py
            from flask import Flask
            from flask import session from pro_flask.utils.session import MySessionInterface app = Flask(__name__) app.secret_key = 'A0Zr98j/3yX R~XHH!jmN]LWX/,?RT' app.session_interface = MySessionInterface() @app.route('/login.html', methods=['GET', "POST"]) def login(): print(session) session['user1'] = 'alex' session['user2'] = 'alex' del session['user2'] return "内容" if __name__ == '__main__': app.run() session.py #!/usr/bin/env python # -*- coding:utf-8 -*- import uuid import json from flask.sessions import SessionInterface from flask.sessions import SessionMixin from itsdangerous import Signer, BadSignature, want_bytes class MySession(dict, SessionMixin): def __init__(self, initial=None, sid=None): self.sid = sid self.initial = initial super(MySession, self).__init__(initial or ()) def __setitem__(self, key, value): super(MySession, self).__setitem__(key, value) def __getitem__(self, item): return super(MySession, self).__getitem__(item) def __delitem__(self, key): super(MySession, self).__delitem__(key) class MySessionInterface(SessionInterface): session_class = MySession container = {} def __init__(self): import redis self.redis = redis.Redis() def _generate_sid(self): return str(uuid.uuid4()) def _get_signer(self, app): if not app.secret_key: return None return Signer(app.secret_key, salt='flask-session', key_derivation='hmac') def open_session(self, app, request): """ 程序刚启动时执行,需要返回一个session对象 """ sid = request.cookies.get(app.session_cookie_name) if not sid: sid = self._generate_sid() return self.session_class(sid=sid) signer = self._get_signer(app) try: sid_as_bytes = signer.unsign(sid) sid = sid_as_bytes.decode() except BadSignature: sid = self._generate_sid() return self.session_class(sid=sid) # session保存在redis中 # val = self.redis.get(sid) # session保存在内存中 val = self.container.get(sid) if val is not None: try: data = json.loads(val) return self.session_class(data, sid=sid) except: return self.session_class(sid=sid) return self.session_class(sid=sid) def save_session(self, app, session, response): """ 程序结束前执行,可以保存session中所有的值 如: 保存到resit 写入到用户cookie """ domain = self.get_cookie_domain(app) path = self.get_cookie_path(app) httponly = self.get_cookie_httponly(app) secure = self.get_cookie_secure(app) expires = self.get_expiration_time(app, session) val = json.dumps(dict(session)) # session保存在redis中 # self.redis.setex(name=session.sid, value=val, time=app.permanent_session_lifetime) # session保存在内存中  self.container.setdefault(session.sid, val) session_id = self._get_signer(app).sign(want_bytes(session.sid)) response.set_cookie(app.session_cookie_name, session_id, expires=expires, httponly=httponly, domain=domain, path=path, secure=secure)
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#!/usr/bin/env python
# -*- coding:utf-8 -*-
""" pip3 install redis pip3 install flask-session """ from flask import Flask, session, redirect from flask.ext.session import Session app = Flask(__name__) app.debug = True app.secret_key = 'asdfasdfasd' app.config['SESSION_TYPE'] = 'redis' from redis import Redis app.config['SESSION_REDIS'] = Redis(host='192.168.0.94',port='6379') Session(app) @app.route('/login') def login(): session['username'] = 'alex' return redirect('/index') @app.route('/index') def index(): name = session['username'] return name if __name__ == '__main__': app.run()
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七、蓝图

蓝图用于为应用提供目录划分:

小型应用程序:示例

大型应用程序:示例

其他:

  • 蓝图URL前缀:xxx = Blueprint('account', __name__,url_prefix='/xxx')
  • 蓝图子域名:xxx = Blueprint('account', __name__,subdomain='admin')
    # 前提需要给配置SERVER_NAME: app.config['SERVER_NAME'] = 'wupeiqi.com:5000'
    # 访问时:admin.wupeiqi.com:5000/login.html

八、message

message是一个基于Session实现的用于保存数据的集合,其特点是:使用一次就删除。

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        from flask import Flask, flash, redirect, render_template, request, get_flashed_messages

        app = Flask(__name__)
        app.secret_key = 'some_secret' @app.route('/') def index1(): messages = get_flashed_messages() print(messages) return "Index1" @app.route('/set') def index2(): v = request.args.get('p') flash(v) return 'ok' if __name__ == "__main__": app.run()
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九、中间件

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from flask import Flask, flash, redirect, render_template, request
 
app = Flask(__name__)
app.secret_key = 'some_secret' @app.route('/') def index1(): return render_template('index.html') @app.route('/set') def index2(): v = request.args.get('p') flash(v) return 'ok' class MiddleWare: def __init__(self,wsgi_app): self.wsgi_app = wsgi_app def __call__(self, *args, **kwargs): return self.wsgi_app(*args, **kwargs) if __name__ == "__main__": app.wsgi_app = MiddleWare(app.wsgi_app) app.run(port=9999)
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十、请求扩展

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from flask import Flask, Request, render_template app = Flask(__name__, template_folder='templates') app.debug = True @app.before_first_request def before_first_request1(): print('before_first_request1') @app.before_first_request def before_first_request2(): print('before_first_request2') @app.before_request def before_request1(): Request.nnn = 123 print('before_request1') @app.before_request def before_request2(): print('before_request2') @app.after_request def after_request1(response): print('before_request1', response) return response @app.after_request def after_request2(response): print('before_request2', response) return response @app.errorhandler(404) def page_not_found(error): return 'This page does not exist', 404 @app.template_global() def sb(a1, a2): return a1 + a2 @app.template_filter() def db(a1, a2, a3): return a1 + a2 + a3 @app.route('/') def hello_world(): return render_template('hello.html') if __name__ == '__main__': app.run()
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调用方式:{{sb(1,2)}}  {{ 1|db(2,3)}}

十一、Flask插件

  • WTForms    
  • SQLAchemy
  • 等...    http://flask.pocoo.org/extensions/

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转载自www.cnblogs.com/panfb/p/8931688.html