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 get the following error:
Invalid syntax for include tag. File contains invalid characters or sequences: (ArgumentError)
../ossvlcm/go.md
Valid syntax:
{% include_relative file.ext param='value' param2='value' %}
The line of code throwing the error:
{% assign temp_url = nPath | append: chapter.file %}{% capture my_include %}{% include_relative {{ temp_url | append: '.md' }} %}{% endcapture %}
and nPath is create with:
{% if page.ePath %}
{% assign nPath = '../ossclvm/' %}
{% endif %}
What I'm trying to do is include a file in from the a different folder from where the index.md resides. It seems to get hung up on the '../' characters but I've seen examples that use this.
So what exactly is wrong and how do I access other content from different folders?
Found out that .. is not supported in Jekyll/Liquid.
I reformatted the folder structure to make this work, index files in the parent folders to the content files.
Not a great solution
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 }} %}
I'm trying to output the contents of a variable in raw format. Right now I have something like this:
{{ content }}
but I want to not do any processing of the page content. So if my page content is:
this text should be {{ literal }}
I would like it to generate html corresponding to exactly that, i.e. not do any variable expansion on "{{ literal }}". Is there a way to do this? I had expected a filter to be able to do this but I can't find it.
Thank you.
Make your page content this:
this text should be {% raw %}{{ literal }}{% endraw %}
Or you could do:
{% raw %}
this text should be {{ literal }}
{% endraw %}
And then on the page you'll see:
this text should be {{ literal }}
The raw tags are mentioned in the documentation here.
I have a page say index.html and a file with liquid code called tags. I want to pass a parameter which I specify in index.html to a liquid call in tags. Namely,
index.html
<div>
{% include tags param="site.categories" %}
</div>
Tags
{% assign tags_list = {{ include.param }} %}
...
The {% assign tags_list = {{ include.param }} %} does not work for some reason. Is it possible to do so because this allows me to use tags file for multiple purposes? Instead of writing liquid calls in every page Iwould be able to just do {% include tags param="something" %}. Thanks.
Well, {% include tags param="site.categories" %} is not passing the site.categories hash but the "site.categories" string.
The right syntax is :
{% include tags.html param=site.categories %}