将表单验证错误传递回 Wagtail 页面模板答案

【问题标题】：Pass form validation errors back to Wagtail Page template将表单验证错误传递回 Wagtail 页面模板
【发布时间】：2020-03-13 16:35:44
【问题描述】：

我有一个用于呈现表单的 Wagtail Page 模型。我已经覆盖了get_context 和serve 方法以将表单作为页面上下文传递，然后在收到POST 请求时对其进行验证：

class RegistrationPage(Page):
    ...

    def get_context(self, request, *args, **kwargs):
        # Avoid circular dependency
        from registration.forms import RegistrationForm

        context = super().get_context(request)

        context["form"] = RegistrationForm

        return context

    def serve(self, request, *args, **kwargs):
        # Avoid circular dependency
        from registration.forms import RegistrationForm

        if request.method == "POST":
            registration_form = RegistrationForm(request.POST)

            if registration_form.is_valid():
                registration = registration_form.save()

                return redirect("/")
            else:
                # How do I pass the form with validation errors to the page?
                # Note: I already have template logic to render the form errors
                # I just need to pass the invalidated form to the template
        else:
            return super().serve(request)

问题：

当表单验证失败时，如何将表单传递回模板以便用户可以看到验证错误？

【问题讨论】：

标签： python django django-forms django-views wagtail

【解决方案1】：

我找到的答案是将表单附加到 __init__ 方法内的 Page 模型，然后用 serve 方法内的无效表单覆盖表单：

class RegistrationPage(Page):
    ...

    def __init__(self, *args, **kwargs):
        # Avoid circular dependency
        from registration.forms import RegistrationForm

        super().__init__(*args, **kwargs)

        self.registration_form = RegistrationForm

    def get_context(self, request, *args, **kwargs):

        context = super().get_context(request)

        context["form"] = self.registration_form

        return context

    def serve(self, request, *args, **kwargs):
        # Check if form was submitted
        if request.method == "POST":
            registration_form = self.registration_form(request.POST)

            if registration_form.is_valid():
                registration = registration_form.save()

                messages.success(request, 'Registration added successfully!')

                return redirect("/")
            else:
                self.registration_form = registration_form

        return super().serve(request)

【讨论】：