pages/placeholders.py
"""Placeholder module, that's where the smart things happen."""
from pages.widgets_registry import get_widget
from pages import settings
from pages.models import Content, Media
from pages.widgets import ImageInput, FileInput
from pages.utils import slugify
from django import forms
from django.core.mail import send_mail
from django import template
from django.template import TemplateSyntaxError
from django.core.files.storage import default_storage
from django.forms import Textarea, ImageField, CharField, FileField
from django.forms import TextInput
from django.conf import settings as global_settings
from django.utils.translation import ugettext_lazy as _
from django.utils.safestring import mark_safe
from django.utils.text import unescape_string_literal
from django.template.loader import render_to_string
from django.template import RequestContext
from django.core.files.uploadedfile import UploadedFile
import logging
import os
import time
import copy
import uuid
logging.basicConfig()
logger = logging.getLogger("pages")
PLACEHOLDER_ERROR = _("[Placeholder %(name)s had syntax error: %(error)s]")
def parse_placeholder(parser, token):
"""Parse the `PlaceholderNode` parameters.
Return a tuple with the name and parameters."""
params = {}
bits = token.split_contents()
count = len(bits)
error_string = '%r tag requires at least one argument' % bits[0]
if count <= 1:
raise TemplateSyntaxError(error_string)
try:
name = unescape_string_literal(bits[1])
except ValueError:
name = bits[1]
remaining = bits[2:]
simple_options = ['parsed', 'inherited', 'untranslated', 'shared', 'block']
param_options = ['as', 'on', 'with', 'section']
all_options = simple_options + param_options
while remaining:
bit = remaining[0]
if bit not in all_options:
raise TemplateSyntaxError(
"%r is not an correct option for a placeholder" % bit)
if bit in param_options:
if len(remaining) < 2:
raise TemplateSyntaxError(
"Placeholder option '%s' need a parameter" % bit)
if bit == 'as':
params['as_varname'] = remaining[1]
if bit == 'with':
params['widget'] = remaining[1]
if bit == 'on':
params['page'] = remaining[1]
if bit == 'section':
params['section'] = unescape_string_literal(remaining[1])
remaining = remaining[2:]
elif bit == 'parsed':
params['parsed'] = True
remaining = remaining[1:]
elif bit == 'inherited':
params['inherited'] = True
remaining = remaining[1:]
elif bit == 'untranslated':
params['untranslated'] = True
remaining = remaining[1:]
elif bit == 'shared':
params['shared'] = True
remaining = remaining[1:]
elif bit == 'block':
remaining = remaining[1:]
nodelist = parser.parse(('endplaceholder',))
parser.delete_first_token()
params['nodelist'] = nodelist
return name, params
class PlaceholderNode(template.Node):
"""This template node is used to output and save page content and
dynamically generate input fields in the admin.
:param name: the name of the placeholder you want to show/create
:param page: the optional page object
:param widget: the widget you want to use in the admin interface. Take
a look into :mod:`pages.widgets` to see which widgets
are available.
:param parsed: if the ``parsed`` word is given, the content of the
placeholder is evaluated as template code, within the current
context.
:param as_varname: if ``as_varname`` is defined, no value will be
returned. A variable will be created in the context
with the defined name.
:param inherited: inherit content from parent's pages.
:param untranslated: the placeholder's content is the same for
every language.
"""
field = CharField
widget = TextInput
def __init__(
self, name, page=None, widget=None, parsed=False,
as_varname=None, inherited=False, untranslated=False,
has_revision=True, section=None, shared=False, nodelist=None):
"""Gather parameters for the `PlaceholderNode`.
These values should be thread safe and don't change between calls."""
self.page = page or 'current_page'
self.name = name
self.ctype = name.replace(" ", "_")
if widget:
self.widget = widget
self.parsed = parsed
self.inherited = inherited
self.untranslated = untranslated
self.as_varname = as_varname
self.section = section
self.shared = shared
self.nodelist = nodelist or [] # should be an iterable
self.found_in_block = None
def get_widget(self, page, language, fallback=Textarea):
"""Given the name of a placeholder return a `Widget` subclass
like Textarea or TextInput."""
if isinstance(self.widget, str):
widget = get_widget(self.widget)
else:
widget = self.widget
try:
return widget(page=page, language=language)
except:
pass
return widget()
def get_extra_data(self, data):
"""Get eventual extra data for this placeholder from the
admin form. This method is called when the Page is
saved in the admin and passed to the placeholder save
method."""
result = {}
for key in list(data.keys()):
if key.startswith(self.ctype + '-'):
new_key = key.replace(self.ctype + '-', '')
result[new_key] = data[key]
return result
def get_field(self, page, language, initial=None):
"""The field that will be shown within the admin."""
if self.parsed:
help_text = _('Note: This field is evaluated as template code.')
else:
help_text = ''
widget = self.get_widget(page, language)
label = _(self.name.replace("_", " ")).capitalize()
return self.field(
widget=widget, initial=initial, label=label,
help_text=help_text, required=False)
def save(self, page, language, data, change, extra_data=None):
"""Actually save the placeholder data into the Content object."""
# if this placeholder is untranslated, we save everything
# in the default language
if self.untranslated:
language = settings.PAGE_DEFAULT_LANGUAGE
if self.shared:
page = None
# the page is being changed
if change:
# we need create a new content if revision is enabled
if(settings.PAGE_CONTENT_REVISION and self.name
not in settings.PAGE_CONTENT_REVISION_EXCLUDE_LIST):
Content.objects.create_content_if_changed(
page,
language,
self.ctype,
data
)
else:
Content.objects.set_or_create_content(
page,
language,
self.ctype,
data
)
# the page is being added
else:
Content.objects.set_or_create_content(
page,
language,
self.ctype,
data
)
def get_content(self, page_obj, lang, lang_fallback=True):
if self.untranslated:
lang = settings.PAGE_DEFAULT_LANGUAGE
lang_fallback = False
if self.shared:
return Content.objects.get_content(
None, lang, self.ctype, lang_fallback)
content = Content.objects.get_content(
page_obj, lang, self.ctype, lang_fallback)
if self.inherited and not content:
for ancestor in page_obj.get_ancestors():
content = Content.objects.get_content(
ancestor, lang,
self.ctype, lang_fallback)
if content:
break
return content
def get_lang(self, context):
if self.untranslated:
lang = settings.PAGE_DEFAULT_LANGUAGE
else:
lang = context.get('lang', settings.PAGE_DEFAULT_LANGUAGE)
return lang
def get_content_from_context(self, context):
if self.untranslated:
lang_fallback = False
else:
lang_fallback = True
if self.shared:
return self.get_content(
None,
self.get_lang(context),
lang_fallback)
if self.page not in context:
return ''
# current_page can be set to None
if not context[self.page]:
return ''
return self.get_content(
context[self.page],
self.get_lang(context),
lang_fallback)
def get_render_content(self, context):
if self.nodelist:
with context.push():
context['content'] = self.get_content_from_context(context)
output = self.nodelist.render(context)
return mark_safe(output)
return mark_safe(self.get_content_from_context(context))
def render_parsed(self, context, content):
try:
content_template = template.Template(content, name=self.name)
new_content = mark_safe(content_template.render(context))
except TemplateSyntaxError as error:
if global_settings.DEBUG:
new_content = PLACEHOLDER_ERROR % {
'name': self.name,
'error': error,
}
else:
new_content = ''
return new_content
def edit_tag(self):
return u"""<!--placeholder ;{};-->""".format(self.name)
def render(self, context):
"""Output the content of the `PlaceholdeNode` as a template."""
content = self.get_render_content(context)
request = context.get('request')
render_edit_tag = False
if request and request.user.is_staff and request.COOKIES.get('enable_edit_mode'):
render_edit_tag = True
if not content:
if not render_edit_tag:
return ''
return self.edit_tag()
if self.parsed:
content = self.render_parsed(context, content)
if self.as_varname is None:
if not render_edit_tag:
return content
return content + self.edit_tag()
context[self.as_varname] = content
return ''
def __repr__(self):
return "<Placeholder Node: %s>" % self.name
def get_filename(page, content_type, data):
"""
Generate a stable filename using the original filename of the type.
"""
avoid_collision = uuid.uuid4().hex[:8]
name_parts = data.name.split('.')
if len(name_parts) > 1:
name = slugify('.'.join(name_parts[:-1]), allow_unicode=True)
ext = slugify(name_parts[-1])
name = name + '.' + ext
else:
name = slugify(data.name)
filename = os.path.join(
settings.PAGE_UPLOAD_ROOT,
'page_' + str(page.id),
content_type + '-' + avoid_collision + '-' + name
)
return filename
class FilePlaceholderNode(PlaceholderNode):
"""A `PlaceholderNode` that saves one file on disk.
`PAGE_UPLOAD_ROOT` setting define where to save the file.
"""
def get_field(self, page, language, initial=None):
help_text = ""
widget = FileInput(page, language)
return FileField(
widget=widget,
initial=initial,
help_text=help_text,
required=False
)
def save(self, page, language, data, change, extra_data=None):
if self.shared:
page = None
if extra_data and 'delete' in extra_data:
return super(FilePlaceholderNode, self).save(
page,
language,
"",
change
)
return
if extra_data and 'revision' in extra_data:
return super(FilePlaceholderNode, self).save(
page,
language,
extra_data['revision'],
change
)
return
if extra_data and 'selected' in extra_data and extra_data['selected']:
return super(FilePlaceholderNode, self).save(
page,
language,
extra_data['selected'],
change
)
return
filename = ''
if change and data:
# the image URL is posted if not changed
if not isinstance(data, UploadedFile):
return
filename = get_filename(page, self.ctype, data)
filename = default_storage.save(filename, data)
media = Media(url=filename)
media.save()
return super(FilePlaceholderNode, self).save(
page,
language,
filename,
change
)
class ImagePlaceholderNode(FilePlaceholderNode):
"""A `PlaceholderNode` that saves one image on disk.
`PAGE_UPLOAD_ROOT` setting define where to save the image.
"""
def get_field(self, page, language, initial=None):
help_text = ""
widget = ImageInput(page, language)
return ImageField(
widget=widget,
initial=initial,
help_text=help_text,
required=False
)
class ContactForm(forms.Form):
"""
Simple contact form
"""
email = forms.EmailField(label=_('Your email'))
subject = forms.CharField(
label=_('Subject'), max_length=150)
message = forms.CharField(
widget=forms.Textarea(), label=_('Your message'))
class ContactPlaceholderNode(PlaceholderNode):
"""A contact `PlaceholderNode` example."""
def render(self, context):
request = context.get('request', None)
if not request:
raise ValueError('request not available in the context.')
if request.method == 'POST':
form = ContactForm(request.POST)
if form.is_valid():
data = form.cleaned_data
recipients = [adm[1] for adm in global_settings.ADMINS]
try:
send_mail(
data['subject'], data['message'],
data['email'], recipients, fail_silently=False)
return _("Your email has been sent. Thank you.")
except:
return _("An error as occured: your email has not been sent.")
else:
form = ContactForm()
renderer = render_to_string(
'pages/contact.html', {'form': form}, RequestContext(request))
return mark_safe(renderer)
class JsonPlaceholderNode(PlaceholderNode):
"""
A `PlaceholderNode` that try to return a deserialized JSON object
in the template.
"""
def get_render_content(self, context):
import json
content = self.get_content_from_context(context)
try:
return json.loads(str(content))
except:
logger.warning("JsonPlaceholderNode: coudn't decode json")
return content
class MarkdownPlaceholderNode(PlaceholderNode):
"""
A `PlaceholderNode` that return HTML from MarkDown format
"""
widget = Textarea
def render(self, context):
"""Render markdown."""
import markdown
content = self.get_content_from_context(context)
return markdown.markdown(content)