将 current_user 从 Flask-Login 传递到 Plotly Dash 应用程序

Question

我正在尝试构建一个集成在 Flask 应用程序中的 Dash 应用程序。一切似乎都运行良好，但是当我尝试在 Dash 应用程序中显示登录用户时，它显示为“无”。我的应用程序结构如下：example/example/  dashapp/    static/      custom-css.css    templates/      base.html      home.html      login.html    __init__.py    app1.py    forms.py    models.py    routes.py  application.py  config.py  users.db我的 Dash 应用程序位于app1.py. 我尝试了几种方法通过current_user但没有成功。虽然它出来很好home.html。我想问题在于我的应用程序位于单独的文件中，而不是routes.py.这是代码app.py：import dashimport dash_html_components as htmlfrom dashapp import applicationfrom flask_login import login_required, current_userapp1 = dash.Dash(__name__, server = application, routes_pathname_prefix = '/app1/', assets_folder = 'static', assets_url_path = '/static')app1.scripts.config.serve_locally = Trueapp1.css.config.serve_locally = Trueapp1.layout = html.Div(    children = '{}'.format(current_user))for view_func in app1.server.view_functions:    if view_func.startswith('/app1/'):        app1.server.view_functions[view_func] = login_required(app1.server.view_functions[view_func])routes.py代码：from flask import render_template, flash, redirect, url_for, requestfrom flask_login import login_user, logout_user, current_user, login_requiredfrom werkzeug.urls import url_parsefrom dashapp import application, dbfrom dashapp.forms import LoginFormfrom dashapp.models import Userfrom dashapp import [e-mail]('/')@application.route('/home')@login_requireddef home():    return render_template('home.html')其他脚本几乎是标准的，除非真的需要它们，否则我不会将它们包含在问题中。请建议如何克服我的问题。谢谢！

Answer 1

我设法在一些帮助下解决了这个问题。以防万一有人卡住，请参阅下面的更新代码。

添加session了行以将当前用户名存储在routes.py：

from flask import render_template, flash, redirect, url_for, request, session

from flask_login import login_user, logout_user, current_user, login_required

from werkzeug.urls import url_parse

from dashapp import application, db

from dashapp.forms import LoginForm

from dashapp.models import User

from dashapp import app1

@application.route('/')

@application.route('/home')

@login_required

def home():

    return render_template('home.html')

@application.route('/login', methods=['GET', 'POST'])

def login():

    if current_user.is_authenticated:

        session['username'] = current_user.username

        return redirect(url_for('home'))

    form = LoginForm()

    if form.validate_on_submit():

        session['username'] = form.username.data

        user = User.query.filter_by(username=form.username.data).first()

        if user is None or not user.check_password(form.password.data):

            flash('Invalid username or password')

            return redirect(url_for('login'))

        login_user(user, remember=form.remember_me.data)

        next_page = request.args.get('next')

        if not next_page or url_parse(next_page).netloc != '':

            next_page = url_for('home')

        return redirect(next_page)

    return render_template('login.html', form=form)

@application.route('/logout')

def logout():

    session.pop('username', None)

    logout_user()

    return redirect(url_for('login'))

在session回调中app1.py：

import dash

import dash_html_components as html

from dash.dependencies import Input, Output

from dashapp import application

from flask_login import login_required

from flask import session

app1 = dash.Dash(__name__, server = application, routes_pathname_prefix = '/app1/', assets_folder = 'static', assets_url_path = '/static')

app1.scripts.config.serve_locally = True

app1.css.config.serve_locally = True

app1.layout = html.Div(

    children = [

        html.Div(id='div2'),

        html.Div(id='div3', children = 'xxxx'),

    ],

)

@app1.callback(

    Output('div2', 'children'),

    [Input('div3', 'children')])

def update_intervalCurrentTime(children):

    return session.get('username', None)

for view_func in app1.server.view_functions:

    if view_func.startswith('/app1/'):

        app1.server.view_functions[view_func] = login_required(app1.server.view_functions[view_func])

Answer 2

面临同样的问题。我想问题是当“应用程序”注册 Dash 应用程序时当前用户尚未初始化。很好的解决方法，虽然看起来有点不安全，因为 Flask 会话只是被编码的。

https://github.com/RafaelMiquelino/dash-flask-login/blob/master/app.py - 我认为更强大的解决方案。它在回调中检查 current_user 并将页面的内容用作输入，因此在页面加载时调用回调。如果用户体验不是问题，您也可以跳过对视图的保护。

这是我如何使用它的简化示例：

@app.callback(

    Output('graph-wrapper', 'children'),

    [Input('page-content', 'children')])

def load_graph(input1):

    if current_user.is_authenticated:

        return dcc.Graph() # Dash Graph populated with current_user data from db

    else:

        return ''