I'm trying to render this part of a template (trying to generate some c++ code)
{% for signal in signals -%}
Signal<{{ signal.type }}> {{ signal.name }};
{% endfor %}
and expecting to get:
Signal<SignalTypeVariable> SignalNameVariable;
but I'm getting:
Signal SignalNameVariable;
Any suggestions?
Found the issue.. I'm displaying the render in a html front end so the tags is interpreted by the browser (even though its in a "pre" tag).
When i inspect the code in debug mode the signal type is there so it should be alright to compile.
Related
I'm building an admin for Flask and SQLAlchemy, and I want to pass the HTML for the different inputs to my view using render_template. The templating framework seems to escape the HTML automatically, so all <"'> characters are converted to HTML entities. How can I disable that so that the HTML renders correctly?
To turn off autoescaping when rendering a value, use the |safe filter.
{{ something|safe }}
Only do this on data you trust, since rendering untrusted data without escaping is a cross-site scripting vulnerability.
MarkupSafe provides Jinja's autoescaping behavior. You can import Markup and use it to declare a value HTML safe from the code:
from markupsafe import Markup
value = Markup('<strong>The HTML String</strong>')
Pass that to the templates and you don't have to use the |safe filter on it.
From the Jinja docs section HTML Escaping:
When automatic escaping is enabled everything is escaped by default
except for values explicitly marked as safe. Those can either be
marked by the application or in the template by using the |safe
filter.
Example:
<div class="info">
{{data.email_content|safe}}
</div>
When you have a lot of variables that don't need escaping, you can use an autoescape override block:
{% autoescape false %}
{{ something }}
{{ something_else }}
<b>{{ something_important }}</b>
{% endautoescape %}
For handling line-breaks specifically, I tried a number of options before finally settling for this:
{% set list1 = data.split('\n') %}
{% for item in list1 %}
{{ item }}
{% if not loop.last %}
<br/>
{% endif %}
{% endfor %}
The nice thing about this approach is that it's compatible with the auto-escaping, leaving everything nice and safe. It can also be combined with filters, like urlize.
Of course it's similar to Helge's answer, but doesn't need a macro (relying instead on Jinja's built-in split function) and also doesn't add an unnecesssary <br/> after the last item.
Some people seem to turn autoescape off which carries security risks to manipulate the string display.
If you only want to insert some linebreaks into a string and convert the linebreaks into <br />, then you could take a jinja macro like:
{% macro linebreaks_for_string( the_string ) -%}
{% if the_string %}
{% for line in the_string.split('\n') %}
<br />
{{ line }}
{% endfor %}
{% else %}
{{ the_string }}
{% endif %}
{%- endmacro %}
and in your template just call this with
{{ linebreaks_for_string( my_string_in_a_variable ) }}
Use the safe filter in your template, and then sanitize the HTML with the bleach library in your view. Using bleach, you can whitelist the HTML tags that you need to use.
This is the safest, as far as I know. I tried both the safe filter and the Markup class, and both ways allowed me to execute unwanted JavaScript. Not very safe!
I have this Liquid template which looks like this:
# /_includes/slideshow.html
{% for image in {{ include.images }} %}
...
{% endfor %}
which I'm trying to use with a YAML file (for my Jekyll site) like this:
# /index.md
{% include slideshow.html images='site.data.homepage_images' %}
The reason I see this failing is because my include variable {{ include.images }} resolves to a string within the for loop. Is there a different way to accomplish this? I'm still rather new to Liquid, YAML, Jekyll, and well, web development altogether, so any help in doing this is much appreciated!
(Note: the problem goes away if I replace {{ include.images }} with site.data.homepage_images.)
Additionally, the reason why I'm doing this (and why that crude fix isn't the solution I'm looking for) is for the ability to inject my image slideshow elsewhere around my site. It'd save a lot of code to abuse my include variable in this way.
Correct syntax in for loop is : {% for image in include.images %}
When i use
{% include folder1/folder1_1/img.jpg %}
it works perfectly, But when i try to generate the filename dynamically let's say :
{%capture filename %} {{'folder1/folder1_1/'}}{{ images[0] }}{{ '.jpg' }}{% endcapture %}
{% include {{ filename }} %}
with images[0] = 'img' for example, i get the error that says :
Liquid Exception: Invalid syntax for include tag. File contains
invalid characters or sequences ...
I Don't understand why including file by providing the complete path(static path) works whereas generating the filename dynamically won't work !
Any help would be more than appreciated.
After more research on the internet it seems that dynamic filename paths can't be added due to the fact that the included files are calculated and added at the compilation phase and not at run time phase.
And compilation phase means dynamic paths aren't yet recognized.
Maybe more luck with :
{% capture filename %}folder1/folder1_1/'{{ images[0] }}.jpg'{% endcapture %}
{% include {{ filename }} %}
Is there something like multiple language highlight syntax in Sublime Text? For example my code might look like this:
{% extends "template.html" %}
{% block content %}
{% if task == 'archimed_spiral' %}
<p>
$\frac{2}{3}$
</p>
{% elif task == 'gcd' %}
{% endif %}
{% endblock %}
Which is LaTeX inside html inside Jinja2. It gets pretty hard to read it properly.
Note
I know about Jinja2 package for Sublime, so it does highlight Jinja2 + html. Maybe I am just asking for too much..
Yes you can embed syntax highlighting. You basically define a start and end pattern, then include an existing scope. See Sublime Text 2: Different language highlighting based on context? (a la Webstorm).
I am working on a client's Django/Mezzanine website that has got some strange issue that I just can't seem to figure out. On the blog page (template of blog_post_list.html) I cannot get the meta title of the page to display, meaning
{% block meta_title %}
{{ blog_page.title }}
{% endblock %}
produces no output in the resulting html. The same holds for the meta description, but I am not worried about it as much. The strange thing is that it seems to work just fine for individual blog entries, as well as all the other pages on the website, except the blog list.
Any ideas?
Nothing is displayed in Django template if you render not existing variable or variable value is None.
First test if {{ blog_page }} renders anything. If it doesn't check if blog_page is in your template context.
You can debug template's context by writing simple custom templatetag, e.g.:
templates/your_template.html:
{% load pdb from debug %}
{% block meta_title %}
{% pdb %}
{{ blog_page.title }}
{% endblock %}
templatetags/debug.py:
from django import template
register = template.Library()
#register.simple_tag(name='pdb', takes_context=True)
def pdb(context, *args, **kwargs):
import ipdb;
ipdb.set_trace()
Apparently, there was a bit of confusion involved: I thought blog_page.title was a standard variable in mezzanine, apparently it is not, it was a custom model created by the previous developer. Since I have basically only the templates and a dump of the DB, it does not appear to be possible to restore the original model for blog_page class, so I simply solved it by supplying a meta title manually in the blog_post_list template.