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Flask flash消息原因会话不可用

flask

Flask flash消息原因会话不可用,flask,Flask,使用官方文件中的精确代码： @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

使用官方文件中的精确代码：

@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')
没有
flash（）
一切正常。但添加时会导致错误，因为没有秘密，会话不可用。以下是一个跟踪：

> 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 -
我读过几篇关于这个错误的帖子，但它们都与Flask会话扩展有关，我不使用它

我还尝试在应用程序中添加
app.secret\u key='super secret key'
，但没有成功

我应该使用Flask Session并进行适当的配置，还是有一种方法可以只使用普通Flask flash（），它可以在幕后处理Session本身

应用程序配置：

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()
堆栈跟踪中非常清楚地指出，没有设置密钥。请确保将密钥设置在正确的位置，例如：

app = Flask(__name__)
app.secret_key = 'asrtarstaursdlarsn'

UPLOAD_FOLDER = ..
附加的跟踪表明您尚未添加密钥。可能您稍后添加了密钥，但应用程序未与更新的代码同步

我正在分享一个在Flask中使用普通flash消息的基本示例

app.py
：

from flask import Flask, render_template, flash

app = Flask(__name__)
app.secret_key = 'super secret'

@app.route('/')
def index():
    flash("Flashing a dummy message")
    return render_template("flash_example.html")

@app.route('/another')
def show_page_without_flash():
    return render_template("flash_example.html")

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

flash\u example.html
：

<!DOCTYPE html>
<html>
    <head><title>Flash example</title></head>
    <body>
        {% with messages = get_flashed_messages() %}
          {% if messages %}
            <ul class=flashes>
            {% for message in messages %}
              <li>{{ message }}</li>
            {% endfor %}
            </ul>
          {% endif %}
        {% endwith %}
        <p>Dummy paragraph</p>
    </body>
</html>


闪光例子
{%with messages=get_flashed_messages（）%}
{%if消息%}

{消息%中的消息为%s}

  • {{message}}
    • 
{%endfor%}

{%endif%}
{%endwith%}
虚拟段落
    使用闪存消息（/）进行路由：

    没有闪存消息的路由（/另一个）：

    添加一个密钥

    可能的副本我没有使用此扩展，正如我在我的question@Dmitry您是否尝试使用
    config
    （非应用程序属性）设置密钥
    app.config['SECRET_KEY']=…
    No，正如我所认为的，它们应该工作相同。我可以试试吗？@Dmitry是的，它们应该工作相同。无论如何，您需要找到设置不起作用的原因。你使用1配置吗？问题是否会在本地重复？ 
    app = Flask(__name__)
app.config['SECRET_KEY'] = 'anystringthatyoulike'