[HFCTF 2021 Final]easyflask

import os
import pickle
from base64 import b64decode
from flask import Flask, request, render_template, session

app = Flask(__name__)
app.config["SECRET_KEY"] = "*******"

User = type('User', (object,), {
   
   
    'uname': 'test',
    'is_admin': 0,
    '__repr__': lambda o: o.uname,
})

@app.route('/', methods=('GET',))
def index_handler():
    if not session.get('u'):
        u = pickle.dumps(User())
        session['u'] = u
    return "/file?file=index.js"

@app.route('/file', methods=('GET'