烧瓶模板和重定向问题

Question

我有一个页面，您可以在其中单击预先选择的图像或上传您自己的图像。我想在这些操作中的任何一个完成后将用户发送到一个新页面。这将是两个操作的同一页面。

这是用户上传图片并随后发送到显示图片的新页面时的代码：

@app.route('/', methods=['GET', 'POST'])
def upload_file():
    if request.method == 'POST':
        file = request.files['file']
        if file and allowed_file(file.filename):
            filename = secure_filename(file.filename)
            file.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))
            return redirect(url_for('uploaded_file', filename=filename))
    return render_template('index.html')


@app.route('/photo/<filename>')
def uploaded_file(filename):
    return render_template('uploaded.html', filename=filename)

为了尝试将这些图像放入这些函数中，我尝试更改图像的 url_for，如下所示：

<img href="{{ url_for('uploaded_file') }}" id="doge1" src="{{ url_for('static', filename='img/doge1.png') }}">
<img href="{{ url_for('uploaded_file') }}" id="doge2" src="{{ url_for('static', filename='img/doge2.jpg') }}">
<img href="{{ url_for('uploaded_file') }}" id="doge3" src="{{ url_for('static', filename='img/doge3.jpg') }}">

但我遇到了构建错误。我认为这是因为我没有上传图片。

如何通过单击我的一张图片重定向到 upload_file 页面？如果我可以将图像名称（即 doge1、doge2 或 doge3）传递给上传的文件函数 where is，那就太好了，但我不确定这是否可能。

这是构建错误消息：

werkzeug.routing.BuildError
BuildError: ('uploaded_file', {}, None)

Traceback (most recent call last)
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1836, in __call__
return self.wsgi_app(environ, start_response)
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1820, in wsgi_app
response = self.make_response(self.handle_exception(e))
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1403, in handle_exception
reraise(exc_type, exc_value, tb)
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1817, in wsgi_app
response = self.full_dispatch_request()
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1477, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1381, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1475, in full_dispatch_request
rv = self.dispatch_request()
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1461, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/Users/metersky/code/doge2/app.py", line 29, in upload_file
return render_template('index.html')
File "/usr/local/lib/python2.7/site-packages/flask/templating.py", line 128, in render_template
context, ctx.app)
File "/usr/local/lib/python2.7/site-packages/flask/templating.py", line 110, in _render
rv = template.render(context)
File "/usr/local/lib/python2.7/site-packages/jinja2/environment.py", line 969, in render
return self.environment.handle_exception(exc_info, True)
File "/usr/local/lib/python2.7/site-packages/jinja2/environment.py", line 742, in handle_exception
reraise(exc_type, exc_value, tb)
File "/Users/metersky/code/doge2/templates/index.html", line 1, in top-level template code
{% block content %}
File "/Users/metersky/code/doge2/templates/index.html", line 31, in block "content"
<img href="{{ url_for('uploaded_file') }}" id="doge1" src="{{ url_for('static', filename='img/doge1.png') }}">
File "/usr/local/lib/python2.7/site-packages/flask/helpers.py", line 312, in url_for
return appctx.app.handle_url_build_error(error, endpoint, values)
File "/usr/local/lib/python2.7/site-packages/flask/app.py", line 1641, in handle_url_build_error
reraise(exc_type, exc_value, tb)
File "/usr/local/lib/python2.7/site-packages/flask/helpers.py", line 305, in url_for
force_external=external)
File "/usr/local/lib/python2.7/site-packages/werkzeug/routing.py", line 1616, in build
raise BuildError(endpoint, values, method)
BuildError: ('uploaded_file', {}, None)

Answer 1

您没有传递 '''uploaded_file''' 的输入参数，因此您会收到错误消息。像这样称呼它：

href="{{ url_for('uploaded_file', filename='whatever') }}" id="doge1" src="{{ url_for('static', filename='img/doge1.png') }}">