Slow rendering on Django 1.7 if Layout objects

Hello,

I’ve been using django crispy forms for quite a while now, and never noticed this issue until now. Maybe it comes from my syntax uising the Layout and Div object. I have DCF 1.4.0.

As soon as I’m using the layout.Layout object with some div inside, the time for rendering the form is extremely slow (1.5 second instead of 100ms).

I have a very simple form:

class TAFilterForm(forms.Form):
    subject = forms.CharField(required=False)
    ss = forms.ChoiceField(choices=models.SS_CHOICES, required=False)
    min_created_at = forms.DateField(required=False)
    max_created_at = forms.DateField(required=False)
    aa = forms.ChoiceField(choices=models.AA_CHOICES, required=False)
    cc = forms.ChoiceField(required=False)
    id = forms.CharField(required=False)

    def __init__(self, *args, **kwargs):
        super(TAFilterForm, self).__init__(*args, **kwargs)
        self.fields['cc'].choices = (('all', _('All')), )
        self.helper = helper.FormHelper()
        self.helper.form_method = 'GET'
        self.helper.add_input(
            layout.Submit('submit', _('Filter')),
        )
        self.helper.add_input(
            layout.Submit('csv', _('Get CSV')),
        )
        self.helper.layout = layout.Layout(
            layout.Div(
                layout.Div('id', css_class='span3'),
                layout.Div('ss', css_class='span3'),
                layout.Div('aa', css_class='span3'),
                layout.Div('cc', css_class='span3'),
                css_class='row-fluid filter-form-div',
            ),
            layout.Div(
                layout.Div('subject', css_class='span4'),
                layout.Div('min_created_at', css_class='span4'),
                layout.Div('max_created_at', css_class='span4'),
                css_class='row-fluid filter-form-div',
            ),
        )

thanks

[rfj001]

Using django’s cached template loader helps speed things up immensely.

Use this code in your settings.py file to use the cached template loader.

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': ['templates'],
        'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug',
                'django.template.context_processors.request',
                'django.contrib.auth.context_processors.auth',
            ],
            'loaders': [
                ('django.template.loaders.cached.Loader', [
                    'django.template.loaders.filesystem.Loader',
                    'django.template.loaders.app_directories.Loader',
                ]),
            ],
        },
    },
]

Without caching even without a Layout object crispy forms seems to take forever to render forms with many fields or formsets with many forms. By using the loader I brought a formset with 8 forms of 3 fields each from 10s rendering time down to 500ms on subsequent loads.

[carltongibson]

It’s worthing looking at the FAQ, which discusses this too. http://django-crispy-forms.readthedocs.io/en/latest/faq.html?highlight=cache#how-fast-is-django-crispy-forms

I’m going to close this as I don’t think it’s an issue per se. (Happy to reconsider if enlightened suggestions arise.)