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How to slice a list in Django template?

I'm doing some pagination in Django. I want to show the pages' number which are ahead of the current page. I am using the following code:
{% for page in blogs_page.paginator.page_range|slice:"0:{{ blogs_page.number }}" %}
But this seems useless; the result does the same as the following:
{% for page in blogs_page.paginator.page_range %}
The slice does not work here. How do I fix this?

Never use {{ }} inside of {% %}, don't do this {% {{ }} %}.
{% for page in blogs_page.paginator.page_range|slice:"0:blogs_page.number" %}
I think it won't work. If I were you I would create a custom tag and executed all the logic there. So, it will look like this:
Template:
{% custom_tag blogs_page as result %}
{% for page in result %}
templatetags/tags.py:
from django import template
register = template.Library()
#register.simple_tag
def custom_tag(bl_page):
return bl.page.paginator.page_range[0:bl_page.number]
Details: custom tags

Using split in a django template

I have a dictionary passed to an html django template:
return render_to_response('showdata.html', context_instance=RequestContext(request, {'dictdati': context} ))
this dictionary has this structure:
{0: 'TO;DEC;1;2012/02/28 15:39:06.000;TO;1234;SI;DI;1234;TO;1\n', 1: 'TO;DEC;1;2012/02/28 15:39:06.000;TO;567;SI;DI;567;TO;1\n'}
and in an html template I need to print some of the values in the each row of the dict. If in a python file I use
for key,val in dictdati.items():
print val.split(';')[0]
it prints the first value correctly (TO) but in an html template
{% for key,val in dictdati.items %}
{{ val.split[0] }}
{% endfor %}
in the browser I receive the error:
TemplateSyntaxError at /getdata/
Could not parse the remainder: '[0]' from 'val.split[0]'
Can someone give me an idea to solve this problem?

you cant just call arbitrary logic in django... this is probably more of a job for the backend if you only want 0th but i think you can use the first filter
{{ my_var.split | first }}

I think I found solution so I made a custom Django filter
The Custom filter code:
from django import template
register = template.Library()
#register.filter
def get_index(value, arg):
return value[int(arg)]
And the HTML code:
{% for key,val in dict.items %}
{{ val|get_index:"0" }}
{% endfor %}
In get_index give the index number needed
Also, I see you have used string and then commas as values I have used it as a list so this code only works for value as list

Dealing with json type data in a template

I am after some advice. I know what I need to do, but not sure how I can do it
I send data to a template that comes from from a database
Let's say the database has two fields
Field one (name)
Name of a person
Field two some json (the json has a structure like this, with many field:value)
{
"field1":"value1",
"field2":"value2"
}
I can output this as
Field one (name) Field two (json)
What I actually want to do though, is loop through the json, and print out the values, so like this
Name of a person field1|field2
I am a bit lost on how I can do that
I tried something like this
{% for anitem in fieldtwo %}
<div>{{ anitem }}</div>
{% endfor %}
But that just seems to print out each character
Is what I need to do achievable? I am thinking I just have the whole approach wrong
Thanks
Grant

In the end, I ended up using another dictionary and then pass that through to the template
I loop through the queryset in the view to populate the dictionary
In the template I then did this (alloweddomains is from the view)
{% for testcaseid, domains in alloweddomains.items %}
{% if listtestcase.id == testcaseid %}
{% for key, value in domains.items %}
<div><a class="sendtolinkdisabled" data-testcasename="{{ listtestcase.name }}" data-testcaseid="{{ $
{% endfor %}
{% endif %}
{% endfor %}
This basically looped through the dictionary and if there was a match to my unique ID I get the data and do something with it
I tried various ways to not need the if statement and just get the right point in the dictionary, but nothing seemed to work (so I took the if approach)
Grant

Return items from RSS feed in Django Templatetags

Django noob here.
I'm trying to add RSS feed items into a django template using templatetags (with classytags).
Here's my code:
from django import template
from classytags.core import Tag
import feedparser
register = template.Library()
class ExampleTag(Tag):
name = 'exampletag'
def render_tag(self, context):
raw_feed = "example.com/feed.rss"
feed = feedparser.parse(raw_feed)
entrylist = {}
for entry in feed.entries:
entrylist[entry.title]
return entrylist
register.tag(ExampleTag)
Then, in the template I can call the ExampleTag with:
{% load my_tag %}
{% exampletag %}
This results in a KeyError at / u'The First Entry In The Feed'
If I change my code to append to a list, the template renders without error and the entire structured list is output in a single string.
This is what I'd like to do:
{% load my_tag %}
{% for item in exampletag %}
<p> {{ item }} </p>
{% endfor %}
However this just fails silently (obviously I'm not passing an interable object to the template)
Any ideas? Is this even a good way to go about doing this?
Thanks in advance.

This code looks highly suspect:
for entry in feed.entries:
entrylist[entry.title]
Shouldn't it be something like this?
for entry in feed.entries:
entrylist[entry.title] = entry # or some value
As it is right now you are trying to index into an empty dictionary and are thus getting a KeyError exception.
But I'm still not sure what you are trying to do. Here are 2 ideas that come to mind that may get you started.
Idea one: it sort of looks like you should write an inclusion tag.
Something like (untested):
#register.inclusion_tag('feed_entries.html'):
def feed_entries():
feed = feedparser.parse('example.rss')
return {'items': feed}
And in feed_entries.html
{% for item in items %}
<p> {{ item }} </p>
{% endfor %}
Then, in some random template where you want the list of items displayed:
{% load feed_tags %}
...
<p>Here are the latest entries:</p>
{% feed_entries %}
...
This is assuming feed contains a list of items you want to render somehow. Thus, whenever you use {% feed_entries %} in a template, your snippet of Python is called, it takes the returned dictionary and renders the feed_entries.html template, and the resulting HTML is placed wherever you wrote {% feed_entries %}.
Idea two: If you really want your tag to return a list of items, you could use an assignment tag:
#register.assignment_tag
def feed_entries():
return feedparser.parse('example.rss')
Then in your template you have to "catch" the result of this tag (the list of items):
{% feed_entries as items %}
{% for item in items %}
<p>{{ item }}</p>
{% endfor %}
But that means you'll have to duplicate the "as" and for-loop stuff in every template. The inclusion tag may save you typing and maintenance if you use it in many templates. But if you wanted to render the list differently in each template it would be more flexible. Say you want it in a list of <p> tags in one, but in a <ul> in another.

How do I access a python list from a django templatetag?

I have created a templatetag that loads a yaml document into a python list. In my template I have {% get_content_set %}, this dumps the raw list data. What I want to be able to do is something like
{% for items in get_content_list %}
<h2>{{items.title}}</h2>
{% endfor %}`

If the list is in a python variable X, then add it to the template context context['X'] = X and then you can do
{% for items in X %}
{{ items.title }}
{% endfor %}
A template tag is designed to render output, so won't provide an iterable list for you to use. But you don't need that as the normal context + for loop are fine.

Since writing complex templatetags is not an easy task (well documented though) i would take {% with %} tag source and adapt it for my needs, so it looks like
{% get_content_list as content %
{% for items in content %}
<h2>{{items.title}}</h2>
{% endfor %}`