Django template IF statement bug - html

Does anyone know how is this even possible that Django HTML-template file:
Length: {{ group_list|length }}
{% if group_list|length == 0 %}
Show Foo
{% else %}
Show Bar
{% endif %}
Returns:
Length: 0
Show Bar
Same problem on FF, Chrome and IE9+. This doesn't make any sense completely. How does one suppose to diagnose the problem?

I'm not entirely sure what's going on with {% if group_list|length == 0 %}, but you can always use if statement to test the emptiness of the list:
{% if group_list %}
Note that django also has length_is filter to test exact length, so your use case would most likely not supported by django.

Related

DBT macro ignores leading if block

I defined a macro that starts with:
{% macro my_macro(table, first=false) %}
{%- if first -%} WITH
{%- else -%} ,
{% endif %}
tmp AS (...
In the compiled SQL I see this is completely ignored. If I paste this exact same block after the first CTE, it inserts fine. If I put any text before the if-block, it will also render the text + content of if-block.
I don't understand this behaviour. How can I make this macro work leading either with WITH or ","?
Even if I replace first with true it doesn't show up.
Additional information:
I'm working with BigQuery and dbt version 0.18.2
After trial and error I realised that using "-" to reduce white space on the first line somehow removes the text coming after it as well.
So
{%- if first -%}
WITH
...
Doesn't work, but
{% if first %}
WITH
...
is fine. It was a simple fix, but I doubt this is expected behaviour.
interesting problem! A couple of questions:
What database are you working with?
What version of dbt are you working with?
Where does first come from in your query?
On Azure Synapse and with dbt version 0.18.1, I was able to successfully use the following:
{% set first = true %}
{%- if first -%}
WITH
{%- else -%} ,
{% endif %}
top_100 AS (
SELECT 100 AS MyNumber
),
top_10 AS (
SELECT TOP 10 * FROM top_100
)
SELECT * FROM top_10

Searching for page in site.pages by path without iteration

I have a path to some page from root in Jekyll as a variable path. I want to get some variables from FrontMatter of that page. How could I find this page in site.pages without iterating over all pages?
I mean something like
{% assign aim = site.pages[path] %}
instead of
{% for p in site.pages %}
{% if p.path == path %}
{% assign aim = p %}
{% endif %}
{% endfor %}
Will this solution be faster for a site with a thousand of pages?
You can use the where liquid filter for this:
{% assign aim = site.pages | where:"path",path %}
Thanks #β.εηοιτ.βε for the hint!
That was what I expected, but when I used this template, I've faced the problem: the output of {{aim.title}} was empty.
The where filter produces list even it consists of just one element! But each filepath in a file system points exactly at one file, so I expected that aim will be the page, not a list. To fix this, I've added first filter:
{% assign aim = site.pages | where:"path",path | first %}
And now aim is the page variable I am searching for.
About speed. This solution builds a site 2X faster on my hardware.

How do i compare a String out of a list in Jinja2 to another string?

I'm using a for loop and inside that forloop i generate tables out of DataBase data.
The thing is that i need to show multiple tables, but the if statement in Jinja2 doesn't seem to work for some reason. I need to check if the string on index 2 of my_list[2] is equal to the 'None'.
{% if '{{my_list[2]}}' == 'None' %}
There is no connection.
{% else %}
There is a GOOD connection.
{% endif %}
Why isn't this working?
{% if not customer_list[2] %}
This does exactly wat i needed.

Counting items in Django templates

Is it possible to tally items being listed as part of the django template within the html?
For example, I have a django template with the following code snippet in it:
<div>
{% for thing in thing_list %}
{% if thing.status == "n" %}
<a>{{ thing.status.count }}</a>
{% endif %}
{% endfor %}
</div>
This django template displays all of the things in a list, and I can call each attribute of the thing and display it, so I know I have access to all of the fields.
I want to count then number of "things" and display that number as text. My current attempt above isn't working. Does anyone have any suggestions?
As Willem says, you should do this in the view. Rather than passing a list of all Things and then checking their status in the template with if, you should filter your Things when querying them from the database in the first place:
thing_list = Thing.objects.filter(status='n')
Then you can do just {{ thing_list.count }} in the template.

Strip url to 1 word in Jekyll

I am building a Jekyll blog, and I have come across an issue with permalinks.
My permalinks to blog posts are set like this in
_config.yml:
permalink: /:page/:categories/:title
It outputs like this when navigating to a blog post:
http://localhost:4000/blog/travel/netherlands-trip-prequesites/
I have some static pages in the site: Blog, Travel
The variable page.url outputs this url: /blog/travel/netherlands-trip-prequesites
The code my navigation bar uses to highlight the current page (giving it an "active" class):
{% assign url = page.url|remove:'index.html' %}
{% for nav in site.navigation %}
{% if nav.href == url %}
<li class="active">{{nav.name}}</li>
{% else %}
<li>{{nav.name}}</li>
{% endif %}
{%endfor%}
It works great when navigating to static pages, however when I click a blog post it doesn't highlight the correct static page. (ex.: If i navigate to a blog post with the url /blog/smth/title it should automatically highlight "Blog" in my navigation. When I navigate to /travel/smth/title it should highlight "Travel")
What I'd like to do is to strip down the output of page.url to its first part. For example I'd like to stip the following output
/blog/travel/netherlands-trip-prequesites
down to
/blog/
Why? So I can use it to check which static page it belongs to and highlight it accordigly.
The easiest way is to use split:
{{ page.url | split:'/' | first }}
That will give you the URL content up to the first / character.
I managed to solve it with three filters:
{{ page.url | replace:'/',' ' | truncatewords: 1 | remove:'...' }}
page.url outputs: /page/cat/title, then replace removes the forward slashes producing: page cat title. truncatewords truncates the string down to one word, producing: page... (for some reason three dots gets inserted after the remaining word). After all this I only needed to remove those dots with remove and voilá, my final string: page.
Hope this helps someone.
The answer provided by PeterInvincible was almost perfect, however, there's no need to get piping to remove involved...
The following also will produce desired output
{{ page.url | replace:'/',' ' | truncatewords: 1,"" }}
And to save it to a variable use capture redirection
{{ capture url_base }}{{ page.url | replace:'/',' ' | truncatewords: 1,"" }}{{ endcapture }}
Which can be called via {{url_base}} or mixed with other processing calls.
Also for file paths instead of URLs page.dir works well if you're not using permalink settings for layout, check the gh-pages branch (specifically _includes/nav_gen.html for functional, though rough'round the edges, example) for hosted examples of similar code examples related to liquid syntax and other magic.
Edits & Updates
The above linked script is now live/mostly-working/modular and auto-serving parsed sub-directories viewed currently at the related https://s0ands0.github.io/Perinoid_Pipes/ project site providing examples of recursive parsing of directories. Including and modding for nearly any theme should be possible just check the commented section at the top for currently recognized commands that maybe passed at inclusion call... on that note of inclusion and modularization here's how to turn the above example code for directory parsing into a function
{% comment %}
# Save this to _include/dir_path_by_numbers.html
# import with the following assigning arguments if needed
# {% include dir_path_by_numbers.html directory_argument_path="blog" directory_argument_depth=1 %}
{% endcomment %}
{% assign default_arg_directory_path = page.url %}
{% assign default_arg_directory_depth = 1 %}
{% if directory_argument_path %}
{% assign directory_to_inspect = directory_argument_path %}
{% else %}
{% assign directory_to_inspect = default_arg_directory_path %}
{% endif %}
{% if directory_argument_depth %}
{% assign directory_to_inspect_depth = directory_argument_path %}
{% else %}
{% assign directory_to_inspect_depth = default_arg_directory_depth %}
{% endif %}
{% comment %}
# Defaults read and assigned now to output results
{% endcomment %}
{{ directory_to_inspect_depth | replace:'/',' ' | truncatewords: directory_to_inspect_depth,"" | remove_first: '/' | replace:' ','/' }}
The above should output directory path lengths of whatever size desired and maybe included as shown previously or if feeling adventurous try what's shown below; though for looping and recursive features look to the linked script for how I've worked around stack size restrictions.
{% capture dir_sub_path %}{{include dir_path_by_numbers.html directory_argument_path="blog" directory_argument_depth=1}}{% endcapture %}
Note above is just speculation, untested, and maybe more buggy than scripts tested and hosted publicly... in other words inspiration.
Simplest way would be using
if page.url contains
example:
<li class="{% if page.url contains '/docs/' %}current{% endif %}">
Docs