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Flask 的 session

@app.route("/", )
def index():
    # 如何设置sessoion
    # 1 导入session
    # 2 给sessoion设置值
    # 设置 session
    session['name'] = "santa"
    session["nam1"] = "kai"
    return "ok"


@app.route("/login/")
def login():
    # 获取 session
    # name = session.get('name')
    print(session["name"])  # santa
    return "login"


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

分析 session 的原理

class SecureCookieSessionInterface(SessionInterface):
   
    salt = "cookie-session"
   
    digest_method = staticmethod(hashlib.sha1)
  
    key_derivation = "hmac"
   
    serializer = session_json_serializer
    session_class = SecureCookieSession

    def get_signing_serializer(self, app):
        if not app.secret_key:
            return None
        signer_kwargs = dict(
            key_derivation=self.key_derivation, digest_method=self.digest_method
        )
        return URLSafeTimedSerializer(
            app.secret_key,
            salt=self.salt,
            serializer=self.serializer,
            signer_kwargs=signer_kwargs,
        )
    # 取session的时候执行的
    def open_session(self, app, request):
        s = self.get_signing_serializer(app)
        if s is None:
            return None
        ##cookie键是SESSION_COOKIE_NAME"=session
        val = request.cookies.get(app.session_cookie_name)

        print("open_session.session_cookie_name,", app.session_cookie_name, )
        if not val:
            return self.session_class()
        max_age = total_seconds(app.permanent_session_lifetime)
        try:
            data = s.loads(val, max_age=max_age)
            print("self.session_class(data)", self.session_class(data) )
            return self.session_class(data)
        except BadSignature:
            return self.session_class()

    #存session的时候执行的
    def save_session(self, app, session, response):
        domain = self.get_cookie_domain(app)
        path = self.get_cookie_path(app)

        # If the session is modified to be empty, remove the cookie.
        # If the session is empty, return without setting the cookie.
        if not session:
            if session.modified:
                response.delete_cookie(
                    app.session_cookie_name, domain=domain, path=path
                )

            return
        # Add a "Vary: Cookie" header if the session was accessed at all.
        if session.accessed:
            response.vary.add("Cookie")

        if not self.should_set_cookie(app, session):
            return
        httponly = self.get_cookie_httponly(app)
        secure = self.get_cookie_secure(app)
        samesite = self.get_cookie_samesite(app)
        expires = self.get_expiration_time(app, session)
        # 把session做了一个加密，把整个session的key--》val,全部加密，的到一个value值,
        #session是一个大字典，
        val = self.get_signing_serializer(app).dumps(dict(session))
        # 他把session加密后得到的val存到cookie里面了
        #cookie键是SESSION_COOKIE_NAME"=session
        print("源码中的session",dict(session))
        print("app.session_cookie_name,",app.session_cookie_name,)
        response.set_cookie(
            app.session_cookie_name,
            val,
            expires=expires,
            httponly=httponly,
            domain=domain,
            path=path,
            secure=secure,
            samesite=samesite,
        )

Flask 的 session

标签：move   val   data   time   add   原理   ace   get   adsi   

原文地址：https://www.cnblogs.com/kai-/p/12521132.html