python - 求助,ValueError: View function did not return a response
問題描述
新手在學(xué)flask開發(fā),看到《python web開發(fā)》第十章的用戶資料,在搞 管理員級別的資料編輯器 那里出問題了,視圖函數(shù)拋出異常,不能返回響應(yīng)百度,谷歌,sof無果。找好久了沒解決,心塞所以來尋求幫助,謝謝能提供幫助的人這是整個文件夾http://pan.baidu.com/s/1kV4sXcr
@main.route(’/edit-profile/<int:id>’, methods=[’GET’, ’POST’])@login_required@admin_requireddef edit_profile_admin(id): user = User.query.get_or_404(id) form = EditProfileAdminForm(user=user) if form.validate_on_submit():user.email = form.email.datauser.username = form.username.datauser.confirmed = form.confirmed.datauser.role = Role.query.get(form.role.data)user.name = form.name.datauser.location = form.location.datauser.about_me = form.about_me.datadb.session.add(user)flash(’The profile has been updated.’)return redirect(url_for(’.user’, username=user.username)) form.email.data = user.email form.username.data = user.username form.confirmed.data = user.confirmed form.role.data = user.role_id form.name.data = user.name form.location.data = user.location form.about_me.data = user.about_me return render_template(’edit_profile.html’, form=form, user=user)表單forms.py:
class EditProfileAdminForm(FlaskForm): email = StringField(’Email’, validators=[Required(), Length(1, 64),Email()]) username = StringField(’Username’, validators=[Required(), Length(1, 64), Regexp(’^[A-Za-z][A-Za-z0-9_.]*$’, 0, ’Username must have only letters,’ ’number, dots or underscores’)]) confirmed = BooleanField(’Confirmed’) role = SelectField(’Role’, coerce=int) name = StringField(’Real name’, validators=[Length(0, 64)]) location = StringField(’Location’, validators=[Length(0, 64)]) about_me = TextAreaField(’About me’) submit = SubmitField(’Submit’)def __init__(self, user, *args, **kwargs):super(EditProfileAdminForm, self).__init__(*args, **kwargs)self.role.choices = [(role.id, role.name) for role in Role.query.order_by(Role.name).all()]self.user = user def validate_email(self, field):if field.data != self.user.email and User.query.filter_by(email=field.date).first(): raise ValidationError(’Emai already registered.’)def validate_username(self, field):if field.data !=self.user.username and User.query.filter_by(username=field.data).first(): raise ValidationError(’Username already in use.’)模板edit_profile.html:
{% extends 'base.html' %}{% import 'bootstrap/wtf.html' as wtf %}{% block title %}Flasky - Edit Profile{% endblock %}{% block page_content %}<p class='page-header'> <h1>Edit Your Profile</h1></p><p class='col-md-4'> {{ wtf.quick_form(form) }}</p>{% endblock %}
問題解答
回答1:網(wǎng)友幫助找到問題了,檢查用戶權(quán)限的自定義裝飾器出問題了 decorators.py :
def permission_required(permission): def decorator(f):@wraps(f)def decorated_function(*args, **kwargs): if not current_user.can(permission):abort(403)return f(*args, **kwargs) # 此行縮進錯誤,應(yīng)在if語句外return decorated_function return decorator
修改過來就可以了。
T.T ,真是自己粗心大意。 python 代碼縮進問題,我特意去查了,網(wǎng)友都建議縮進用 4 個空格,用 1 個 tab 鍵代替風(fēng)險太大,因為各家的編輯器對 tab 鍵定義存在差異,很容易出問題。雖然說我這問題不是出在 tab 鍵上,之后我還是會注意這個問題的。
不過我還有一問題,為什么錯誤頁面拋出的是 視圖函數(shù) View function 的問題, 而不會拋出裝飾器那邊的錯誤,例如( IndentationError ): @admin_required → def permission_required(permission) 謝謝
