I have two blocks that call the same method with same variables. I want to call the method only once, but the result is then outsite the scope of the block tags. I've tried calling this method in the parent template header.html and with a with tag, but nothing seems to work.
This is the layout:
{% extends "header.html" %}
{% load navigation_tags %}
{% block header %}
{% get_section site=site as section %}
{% include "foobar.html" with section=section %}
{% endblock header %}
{% block navigation %}
<nav>
<div class="container">
{% get_section site=site as section %}
{% navigation section.slug %}
</div>
</nav>
{% endblock navigation %}
navigation_tags.py
#register.assignment_tag
def get_parent_section(site):
if site.id == settings.FOOBAR_SITE_ID:
section = Section.objects.get(id=settings.FOOBAR_SECTION_ID)
else:
# This is also a section instance.
return site.default_section
As mentioned by 2pacho in another answer and Fernando Cezar in a comment, the easiest way to share values between different sections is to set it in the template context. If you are using the render shortcut function, you can pass a dict as the context parameter to add a value to the rendering context of the template. That would be a good place to add it and this would be the easiest place to put it.
return render(request, 'template.html', {'section': get_parent_section(site)})
However, if for some reason, you can't include it in the context, you can use a decorator to add memoization to your function, so that it will cache the computation results and return it immediately when called with the same parameters. You can use functools.lru_cache to do so, or it's Django backport at django.utils.lru_cache.lru_cache if you are using Python 2.x.
#register.assignment_tag
#functools.lru_cache()
def get_parent_section(site):
if site.id == settings.FOOBAR_SITE_ID:
section = Section.objects.get(id=settings.FOOBAR_SECTION_ID)
else:
# This is also a section instance.
return site.default_section
I wouldn't call a method outside .py . Think that this is using Jinja2 templates,
it's powerful but not in the way that the backend can be.
What I recommend you doing in this case is to generate a context for the template and use this variables there.
Would be as simple as adding it to your context where it's being generated.
context['site_parent'] = get_parent_section(site)
Think that Jinja2 (html) has to be as simple as possible and that can help you with basic coding and time saving (like loops to print the exact same information or show and hide code depending on the context) but I would keep it as simple you can when rendering.
If you would like you can read official django website about templates https://docs.djangoproject.com/en/2.0/topics/templates/
But from my expirience I would keep the method calls in the views.py
Related
I trying to get the page and the request from context to be able to use pagination inside the block. The only context i get is
context {'self': None, 'value': None}
Is it even possible to have pagination inside a streamfield block?
class CustomStaticBlock(blocks.StaticBlock):
def get_context(self, value):
context = super(CustomStaticBlock, self).get_context(value)
Rendering with
{% include_block block%}
It's now working (within get_context). If someone has the same issue with a StreamField, make sure to render it as:
{% for block in page.body %}
{% include_block block %}
{% endfor %}
The following won't work (empty parent_context):
{% include_block page.body %}
{{ page.body|safe }}
The context from the outer page is available within the block template, but unfortunately not within the get_context method. (This is due to the way the template context is built up - the result of get_context is merged into the parent context.) This is a known limitation:
https://github.com/wagtail/wagtail/pull/2786#issuecomment-230416360
https://github.com/wagtail/wagtail/issues/2824
A possible workaround would be to override the render method (which is admittedly not ideal, because you'd have to repeat some or all of the existing render logic there).
I'm working on a simple blog app in Django, and i'm having trouble figuring out how to dynamically generate the five most recent posts in a side bar. Each of my views are class based and they extend a generic template, each view maps to one template which I believe is the correct way to do it. I've looked for a way to do this using template tags, but it seems Django doesn't like you to put any logic inside of your templates.
The problem I believe is that I want this to exist within my base.html because I want the recent posts to be displayed site-wide, is a view even supposed to map to your base.html or does that cause problems, i'm pretty new with this. I don't know how to approach this, whether i'm supposed to create a new view for base.html or if I should use my template tags, or if I should extend an existing view(but if I do that it won't be site wide?).
I essentially want the following(they're ordered in reverse chronological order)
{% for post in post_list[:4] %}
{{ post.title }}
{% endfor %}
You can use a template tag. More specifically, an inclusion tag is what you need. This allows you to insert a rendered snippet anywhere inside your template via a small view-like piece of code.
For example, create a templatetags/blog_tags.py file (it's important that you create the templatetags folder within your app; Django searches for them here by default) in your blog app and add the following:
from django import template
register = template.Library()
#register.inclusion_tag('blog/snippets/recent_posts.html')
def render_recent_blogposts():
return {
# This is just an example query, your actual models may vary
'post_list': BlogPost.objects.all().order_by("published_on")[:4]
}
now create a blog/snippets/recent_posts.html template (it can be anywhere as long as it mathecs the #register.inclusion_tag(...) above.):
<ul>
{% for post in post_list %}
<li> {{ post.title }}</li>
...
{% endfor %}
</ul>
finally, in your original template, you can now render your template tags:
<aside>
{% load blog_tags %}
{% render_recent_blogposts %}
</aside>
I am hitting a brick wall when it comes to solving this problem. I have a template that is being included in an other template, but I am unable to render any template variables in the included template. I have a separate template tag file for the included template. I am at a total loss right now how to resolve this problem.
I would like to be able to render the field values from my model in the template (which consist of an image, a short description, etc.) I am fairly certain that I am going about this in the wrong way.
Below is my code:
The model:
class AddOnItem(models.Model):
base_product = models.ForeignKey(Product)
base_price = models.DecimalField(max_digits=8, decimal_places=2, default=0.0)
addon_image = models.ImageField(upload_to='uploads/shop/product/images/',
default='uploads/shop/product/images/', help_text='Max width: 450px')
short_description = models.CharField(max_length=255, blank=True)
def __unicode__(self):
return self.base_product.name
The template:
{% load addon_tags %}
{% if items_to_add %}
{% for items in items_to_add %}
<div id="addon-container">
<div id="left-addon" class="addon-container">
<img src="#" class="addon-image">
<p class="addon-description">{{items.short_description}}</p>
</div>
</div>
{% endfor %}
{% endif %}
addon_tags.py:
from django import template
from sho.models import AddOnItem
register = template.Library()
#register.inclusion_tag("foo/templates/v/sho/addon.html", takes_context=True)
def add_on_render():
context['items_to_add'] = AddOnItem()
return context
I imagine I am doing either a lot wrong (my assumption at the moment) or I am missing some minor bit. I have been working on this for several days and have gone over the docs repeatedly. I am simply completely missing something and this has become a major blocker for me. Any help would be appreciated.
Django version 1.4
Edit:
I ended up rewriting the view and did away with the templatetag. Thanks to both Daniel Roseman and Odif Yltsaeb for their replies.
1) From your post you are adding empty, new item into the context in add_on_render templateag.
2) I cant see in your post, WHERE you are using {% add_on_render %} templatetag. You have created templattag, but do not seem to be using it anywhere.
It is bit hard to understand what exactly are you trying to do or why you even need templatetag there.
If you want to display models field value, you do not need templateag for this and all the stuff that you show in your "template" part of this post, could be very well in your main template, which i assume, is not shown in your post.
If you want to use templatetag, then this templatetag should probably recieve AddOnItem istance as parameter like this:
#register.inclusion_tag("foo/templates/v/sho/addon.html", takes_context=True)
def add_on_render(item):
context['items_to_add'] = item
return context
And You could use it in some template like this:
{% load addon_tags %}
{% if items_to_add %}
{% for items in items_to_add %}
<div id="addon-container">
<div id="left-addon" class="addon-container">
<img src="#" class="addon-image">
<p class="addon-description">{% add_on_render items %}</p>
</div>
</div>
{% endfor %}
{% endif %}
and your foo/templates/v/sho/addon.html
would like like this:
{{ items_to_add.short_description }}
But doing it this way seems very unnecessary as you could achieve all that without templatag by using the template code that you already have outside your "main" template.
You haven't posted the template that you are attempting to include the tag in. I suspect you're not calling it at all, because there are a couple of errors that would cause exceptions if you did try and use the tag. You need to do {% add_on_render %} somewhere in your main template.
As I say though there are a couple of errors. Firstly, you don't define context (as an empty dict) before adding the items_to_add key. You can shortcut this by just doing it in one go.
Secondly you've made items_to_add a single, blank, AddOnItem. So in your included template, iterating through items_to_add does nothing at all. Not sure what you are trying to do there. Perhaps you want to pass all AddOnItem instances?
context = {'items_to_add': AddOnItem.objects.all()}
Or maybe you want to filter them by some criteria, in which case you probably want to pass those criteria to the inclusion tag itself:
def add_on_render(product):
context = {'items_to_add': AddOnItem.objects.filter(base_product=product)}
and you would call it from the main template like this:
{% add_on_render my_product %}
if you set "takes_context=True" you should take context as the first argument in decorated function:
#register.inclusion_tag("foo/templates/v/sho/addon.html", takes_context=True)
def add_on_render(context):
context['items_to_add'] = AddOnItem()
....
My app's templatetag code is throwing a KeyError for a missing key (page) in the context variable. In my template, I do not refer to context variables with context.variableKeyName, I just refer to variableKeyName (e.g. {% if is_paginated %}). And in my template, I can refer to the key page without any exceptions.
How should I get the context with the keys it needs into my templatetag?
Here are the details:
I am using django-profiles to return a list of some profiles:
url(r'^profiles/$', 'profiles.views.profile_list',
kwargs={ 'paginate_by':10 },
name='profiles_profile_detail'),
which calls this bit of code here:
https://bitbucket.org/ubernostrum/django-profiles..
In my template, I test {% if is_paginated %} before I call a templatetag:
{% if is_paginated %}{% load paginator %}{% paginator 3 %}{% endif %}
( I am using a templatetag inspired from http://www.tummy.com/.../django-pagination/ updated for django 1.3 http://djangosnippets.org/snippets/2680/ )
But this leads to the KeyError for 'paged'.
The documentation (comments in the class) of http://djangosnippets.org/snippets/2680/ says:
Required context variables: paged: The Paginator.page() instance.
It is also used in the template tag:
paged = context['paged']
You need to provide this context variable for this template tag to work. I think your best bet is to copy the code of profiles.views.profile_list view and add this context variable. It's unfortunately still a function-based view - otherwise extending it would have been a lot cleanier and easier.
the right way to code is:
{% paginator v 3 %}
v - variable that contains the db items
I'm writing a simple blog-like application for Django and am trying to get the effect of having a front page with posts limited to 5, with a comprehensive archive that lists something like 100 posts at a time. (100 is not realistic, just throwing a number out there)
Since the blog post blocks will look exactly the same between the two pages minus the number being shown, I'd like to put the corresponding HTML in a separate template that I can include or link to from the actual templates being rendered. I've looked over the documentation, and the include tag looked promising, but it apparently renders outside of the current context, which is not helpful to my cause, since it wouldn't get the objects to loop through. Outside of that, I can't see any other way to do what I want. Is this possible or am I just out of luck and going to have to violate DRY? Code is below to give you an idea of what I want.
Thanks
#######################
# news/frontpage.html #
#######################
{% extends "news/base.html" %}
{% block site_title %} - Front Page{% endblock %}
{% block center_col %}
{{ block.super }}
View Older Blog Posts
{% endblock %}
{% block blog_rows %}
{% for object in object_list %}
# Blog post content would go here, however it is to be included.
{% endfor %}
{% endblock %}
You're looking for an inclusion tag.
Why don't you filter for the blog posts you want to show in your view? That way you can keep the template the same:
{% for object in blogposts %}
# ...
{% endfor %}
You define blogposts in your view, which either includes 5 or 100 posts.
Ignacio is right that you want an inclusion tag, but you should know that the include tag does not render outside the current context - it very definitely uses the same context as the block it's in.
Your problem is probably that you're trying to call blogpost_set on the object_list - but the relationship is not with the list of objects, it's with each individual object in the list. You'd need to iterate through object_list and then through blogpost_set.all on each one.