Используйте точный код из официальных документов:
@app.route('/', methods=['GET', 'POST'])
def upload_file():
if request.method == 'POST':
...
if file.filename == '':
flash('No selected file')
return redirect(request.url)
if file and allowed_file(file.filename):
..
flash('File was successfully uploaded')
return redirect(url_for('uploaded_file', filename=filename))
return render_template('home.html')
Без flash()
все работает нормально.Но при добавлении это вызывает ошибку. Сессия недоступна, потому что не секрет.Ниже приведен след:
> 127.0.0.1 - - [18/Feb/2019 10:16:21] "POST / HTTP/1.1" 500 -
> 127.0.0.1 - - [18/Feb/2019 10:17:16] "GET / HTTP/1.1" 200 - [2019-02-18 10:17:23,999] ERROR in app: Exception on / [POST]
> Traceback (most recent call last): File
> "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/flask/app.py",
> line 2292, in wsgi_app
> response = self.full_dispatch_request() File "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/flask/app.py",
> line 1815, in full_dispatch_request
> rv = self.handle_user_exception(e) File "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/flask/app.py",
> line 1718, in handle_user_exception
> reraise(exc_type, exc_value, tb) File "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/flask/_compat.py",
> line 35, in reraise
> raise value File "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/flask/app.py",
> line 1813, in full_dispatch_request
> rv = self.dispatch_request() File "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/flask/app.py",
> line 1799, in dispatch_request
> return self.view_functions[rule.endpoint](**req.view_args) File "/home/dvperv/PycharmProjects/astros/app.py", line 39, in upload_file
> flash('No file part') File "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/flask/helpers.py",
> line 410, in flash
> session['_flashes'] = flashes File "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/werkzeug/local.py",
> line 350, in __setitem__
> self._get_current_object()[key] = value File "/home/dvperv/PycharmProjects/astros/venv/lib/python3.6/site-packages/flask/sessions.py",
> line 101, in _fail
> raise RuntimeError('The session is unavailable because no secret ' RuntimeError: The session is unavailable because no secret key was
> set. Set the secret_key on the application to something unique and
> secret.
> 127.0.0.1 - - [18/Feb/2019 10:17:24] "POST / HTTP/1.1" 500 -
Я прочитал несколько сообщений об этой ошибке, но все они относятся к расширению Flask-Session, Я не использую его .
Я также попытался добавить app.secret_key = 'super secret key'
в приложение, без успеха.
Должен ли я использовать Flask Session и выполнить соответствующую настройку, или есть способ просто использовать обычную Flask flash (), которая как-то работаетс сеансами за сценой.
Конфигурация приложения:
app = Flask(__name__)
UPLOAD_FOLDER = ..
ALLOWED_EXTENSIONS = ..
app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER
app.config['MAX_CONTENT_LENGTH'] = 16 * 1024 * 1024
if __name__ == '__main__':
app.run()