from functools import lru_cache
from django import template
from django.conf import settings
from django.forms.formsets import BaseFormSet
from django.template.loader import get_template
from crispy_forms.helper import FormHelper
from crispy_forms.utils import TEMPLATE_PACK, get_template_pack
register = template.Library()
# We import the filters, so they are available when doing load crispy_forms_tags
from crispy_forms.templatetags.crispy_forms_filters import * # NOQA: F403,F401, E402 isort:skip
[docs]
class ForLoopSimulator:
"""
Simulates a forloop tag, precisely::
{% for form in formset.forms %}
If `{% crispy %}` is rendering a formset with a helper, We inject a `ForLoopSimulator` object
in the context as `forloop` so that formset forms can do things like::
Fieldset("Item {{ forloop.counter }}", [...])
HTML("{% if forloop.first %}First form text{% endif %}"
"""
def __init__(self, formset):
self.len_values = len(formset.forms)
# Shortcuts for current loop iteration number.
self.counter = 1
self.counter0 = 0
# Reverse counter iteration numbers.
self.revcounter = self.len_values
self.revcounter0 = self.len_values - 1
# Boolean values designating first and last times through loop.
self.first = True
self.last = 0 == self.len_values - 1
[docs]
def iterate(self):
"""
Updates values as if we had iterated over the for
"""
self.counter += 1
self.counter0 += 1
self.revcounter -= 1
self.revcounter0 -= 1
self.first = False
self.last = self.revcounter0 == self.len_values - 1
[docs]
class BasicNode(template.Node):
"""
Basic Node object that we can rely on for Node objects in normal
template tags. I created this because most of the tags we'll be using
will need both the form object and the helper string. This handles
both the form object and parses out the helper string into attributes
that templates can easily handle.
"""
def __init__(self, form, helper, template_pack=None):
self.form = form
self.helper = helper
self.template_pack = template_pack or get_template_pack()
[docs]
def get_render(self, context):
"""
Returns a `Context` object with all the necessary stuff for rendering the form
:param context: `django.template.Context` variable holding the context for the node
`self.form` and `self.helper` are resolved into real Python objects resolving them
from the `context`. The `actual_form` can be a form or a formset. If it's a formset
`is_formset` is set to True. If the helper has a layout we use it, for rendering the
form or the formset's forms.
"""
# Nodes are not thread safe in multithreaded environments
# https://docs.djangoproject.com/en/dev/howto/custom-template-tags/#thread-safety-considerations
if self not in context.render_context:
context.render_context[self] = (
template.Variable(self.form),
template.Variable(self.helper) if self.helper else None,
)
form, helper = context.render_context[self]
actual_form = form.resolve(context)
if self.helper is not None:
helper = helper.resolve(context)
else:
# If the user names the helper within the form `helper` (standard), we use it
# This allows us to have simplified tag syntax: {% crispy form %}
helper = FormHelper() if not hasattr(actual_form, "helper") else actual_form.helper
# use template_pack from helper, if defined
try:
if helper.template_pack:
self.template_pack = helper.template_pack
except AttributeError:
pass
self.actual_helper = helper
# We get the response dictionary
is_formset = isinstance(actual_form, BaseFormSet)
response_dict = self.get_response_dict(helper, context, is_formset)
node_context = context.__copy__()
node_context.update({"is_bound": actual_form.is_bound})
node_context.update(response_dict)
final_context = node_context.__copy__()
# If we have a helper's layout we use it, for the form or the formset's forms
if helper and helper.layout:
if not is_formset:
actual_form.form_html = helper.render_layout(
actual_form, node_context, template_pack=self.template_pack
)
else:
forloop = ForLoopSimulator(actual_form)
helper.render_hidden_fields = True
for form in actual_form:
node_context.update({"forloop": forloop})
node_context.update({"formset_form": form})
form.form_html = helper.render_layout(form, node_context, template_pack=self.template_pack)
forloop.iterate()
if is_formset:
final_context["formset"] = actual_form
else:
final_context["form"] = actual_form
return final_context
[docs]
def get_response_dict(self, helper, context, is_formset):
"""
Returns a dictionary with all the parameters necessary to render the form/formset in a template.
:param context: `django.template.Context` for the node
:param is_formset: Boolean value. If set to True, indicates we are working with a formset.
"""
if not isinstance(helper, FormHelper):
raise TypeError("helper object provided to {% crispy %} tag must be a crispy.helper.FormHelper object.")
attrs = helper.get_attributes(template_pack=self.template_pack)
form_type = "form"
if is_formset:
form_type = "formset"
# We take form/formset parameters from attrs if they are set, otherwise we use defaults
response_dict = {
"%s_action" % form_type: attrs["attrs"].get("action", ""),
"%s_attrs" % form_type: attrs.get("attrs", ""),
"%s_class" % form_type: attrs["attrs"].get("class", ""),
"%s_id" % form_type: attrs["attrs"].get("id", ""),
"%s_method" % form_type: attrs.get("form_method", "post"),
"%s_tag" % form_type: attrs.get("form_tag", True),
"disable_csrf": attrs.get("disable_csrf", False),
"error_text_inline": attrs.get("error_text_inline", True),
"field_class": attrs.get("field_class", ""),
"field_template": attrs.get("field_template", ""),
"flat_attrs": attrs.get("flat_attrs", ""),
"form_error_title": attrs.get("form_error_title", None),
"form_show_errors": attrs.get("form_show_errors", True),
"form_show_labels": attrs.get("form_show_labels", True),
"formset_error_title": attrs.get("formset_error_title", None),
"help_text_inline": attrs.get("help_text_inline", False),
"include_media": attrs.get("include_media", True),
"inputs": attrs.get("inputs", []),
"is_formset": is_formset,
"label_class": attrs.get("label_class", ""),
"template_pack": self.template_pack,
}
# Handles custom attributes added to helpers
for attribute_name, value in attrs.items():
if attribute_name not in response_dict:
response_dict[attribute_name] = value
if "csrf_token" in context:
response_dict["csrf_token"] = context["csrf_token"]
return response_dict
# {% crispy %} tag