尝试使用客户错误处理程序时出现“ KeyError：无”错误-Flask

Question

I have the following:

def handle_error_404(error):
    flash('Server says: {0}'.format(error), 'error')
    return render_template('404.html', selected_menu_item=None)


def handle_error_500(error):
    flash('Server says: {0}'.format(error), 'error')
    return render_template('500.html', selected_menu_item=None)


def init_error_handlers(app):
    if app:
        app.error_handler_spec[None][404] = handle_error_404
        app.error_handler_spec[None][500] = handle_error_500

I was following a tutorial on how to use customer error handlers, but I can't seem to find a way around this error. How can I get around this?

Answer 1

The flask docs say you should register an error handler using the errorhandler decorator. An example using your code:

def handle_error_404(error):
    flash('Server says: {0}'.format(error), 'error')
    return render_template('404.html', selected_menu_item=None)


def handle_error_500(error):
    flash('Server says: {0}'.format(error), 'error')
    return render_template('500.html', selected_menu_item=None)


def init_error_handlers(app):
    if app:
        app.errorhandler(404)(handle_error_404)
        app.errorhandler(500)(handle_error_500)

Alternatively:

def init_error_handlers(app):
    if app:
        @app.errorhandler(404)
        def handle_error_404(error):
            flash('Server says: {0}'.format(error), 'error')
            return render_template('404.html', selected_menu_item=None)

        @app.errorhandler(500)
        def handle_error_500(error):
            flash('Server says: {0}'.format(error), 'error')
            return render_template('500.html', selected_menu_item=None)