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How to get variables between the curly brackets in django template in django views?

I have django template file. Now i want to get all the variables list that are between curly brackets. I think it is possible with the regular expressions. And i read about regular expressions. But there is no function i found to be helpful.
template code snippet:
<tr><td>
Dear Candidate,<br/>
Welcome to Creative Talent Management!<br/>
We have created an account for you. Here are your details:<br/>
Name:{{name}}<br/>
Email:{{email}}<br/>
Organization:{{organization}}<br/>
Password:{{password}}<br/>
</td></tr>
I want to get name,email,organization,password in my python function.
Right now i'm reading the template but getting empty list.
if created:
temp_path = str(instance.html_template.path)
html_file = open(instance.html_template.path, 'r', encoding='utf-8')
file_data = html_file.read()
render_param = re.findall("^{{ . }}$", file_data)
print("html param ",render_param)

That's sort of back-to-front. You would normally pass all the variables which might be used from your view to the template rendering through the context. It doesn't matter if one or more of the context variables are unused by the template. Of course, you should have a test which catches variable name spelling errors ({{usernmae}} will render as null string without error ).
For checking the template, you might simply grep '{{' some_template.html, or write something in Python to get (say) an alphabetically sorted list of variable names. But that's a program-development aid, not a part of the Django server code.
If you really wanted to, you could just open the template file and write similar Python code as part of your view. But, why??

Django not rendering python variable in template

I have a string variable in a Python file that I am trying to render in my HTML template. The variable is called contacts, and in my template, I have {{contacts|default:"null"}}. From the documentation, it seems like that should work, but the template keeps coming up with the null keyword. I've scoured the documentation and found nothing. Probably a super simple thing I'm overlooking that has frustrated me to no end.
In the python file, I'm using an API to get a JSON and unloading it into a dictionary (don't know all the specific terms), where I then extract the value I need into a string:
...
dict_data = dict(json.loads(data))
contacts = str(dict_data["contact_count"])
Then in my HTML file:
<p class="spotbanner">
{{contacts|default:"null"}} spots left!
</p>
Is there something else I'm missing? Something super simple that I just don't understand about Django despite having used this method before? Happy to provide more information.

Poked around a teensy bit more and found an answer. For those like me:
It's not as simple as just rendering the variable. Django doesn't see it until you import the .py file into your views.py. Once you've done that, you'll need to create a context in the method that renders the page. For me, it finally worked once I added:
context = context = {"contacts":contacts}

Maybe a simple example might help you. Calling render_to_string to load a template HTML in Django.
Be aware the key name will map to the variable name in the HTML
from django.template.loader import render_to_string
rendered = render_to_string('my_template.html', {'foo': 'bar'})
# {{foo}} will show string 'bar' in HTML
Referral: https://docs.djangoproject.com/en/3.1/topics/templates/
Accordingly, by your cases, suppose we'll see something like
contacts = str(dict_data["contact_count"])
# if you want to show contact_count --> use {{contact_count}} in HTML
rendered = render_to_string('my_template.html', contacts)

How to include context variable in a wagtail cms field?

I am looking for a way to render a variable that will be available in the context of the the page where the cms page will be rendered.
Ex:
I have in the context the logged in user and I also have the last transaction he made on the website.
I would like the text in the rich text field in Wagtail to be like this so that the marketing team can tweak the copy.
Hello ||firstname|| thanks for your purchase. ||productname|| will be
shipped to you soon. The expected delivery date is
||expected_delivery_date||
To be less confusing I replace the double brackets by double pipes to show that the templating system does not need to be django templates for those ones. Simple templating is enough maybe using https://docs.python.org/3.4/library/string.html#template-strings
I think I can achieve this by doing:
A stream field that would have blocks of rich text field and a custom block with the possible context variable they can use
A custom render function that would regex and replace the merge tags in the rich text block with the context values
Create a new filter for simple templating. ex: {{ page.body|richtext|simpletemplate }}
Is there any more obvious way or out of the box way to do templating from within a rich text field?

It would be clunky with a separate streamfield block for each inserted context variable. You'd have to override the default rendering which wraps elements in div tags. However I like that it is more foolproof for the editors.
I've done something like the custom rendering before, but with simple TextFields for formatting special offer code messages. Wagtail editors were given the following help_text to illustrate:
valid_placeholders = ['offer_code', 'month_price']
template_text = models.TextField(
_('text'),
help_text="Valid placeholder values are: {all_valid}. Write as {{{example}}}".format(
all_valid=", ".join(valid_placeholders),
example=valid_placeholders[0],
)
)
This rendered as Valid placeholder values are: offer_code, month_price. Write as {{offer_code}}.
Then in the view:
template_keys = [i[1] for i in Formatter().parse(template_text)]
…and continued rendering from there. Remember to validate the field appropriately using the above Formatter().parse() function too.
I used Django's template formatting rather than Python's string.format() because it fails silently, but you could go with string.format() if cleaned adequately.
The custom template filter would feel easiest to me, so I'd start with that approach and switch to a custom render function if I ran into hurdles.

I found an easier way to do this. I wanted my editors to be able to create pages with dynamic customization to the individual user. With this, my editors are actually able to put template variables into any type of content block as {{ var }} which works just like the Django templating language. For my use case, I am allowing my editors to create email content in the CMS, then pulling that to send the emails:
This is the function to call:
def re_render_html_template(email_body, context):
"""
This function takes already rendered HTML anbd re-renders it as a template
this is necessary because variables added via the CMS are not caught by the
first rendering because the first rendering is rendering the containing block,
so instead they are rendered as plaintext in content the first render, e.g., {{ var }}
Example:
input: <p>Hey {{ user_account.first_name }}, welcome!</p>
output: <p>Hey Brett, welcome!</p>
#param email_body: html string
#type email_body: str
#param context: context dictionary
#type context: dict
#return: html string
#rtype: str
"""
from django.template import Context
from django.template import Template
template = Template(email_body)
context = Context(context)
email_body = template.render(context)
return email_body
Then I call it like so:
email_body = render_to_string(template, context)
# need to re-render to substitute tags added via CMS
email_body = re_render_html_template(email_body, context)

Django / Python: Convert Markdown to Secure HTML

I'm accepting Markdown and need to convert it to HTML to render securely in Django. Right now I'm accepting the form.cleaned_data and converting it to HTML with:
import markdown
html_body = markdown.markdown(body_markdown, safe_mode=True)
html_body = html_body.replace('[HTML_REMOVED]', '')
return html_body
In the template, I'm rendering it as :
{{ object.content|safe|capfirst }}
However if you post:
0;url=javascript:alert('hi');" http-equiv="refresh
The JS will render so XSS is possible.

django's built in safe template tag means that you are marking that variable as ok to output, i.e. you know that it's contents are safe:
safe: Marks a string as not requiring further HTML escaping prior to output.
Django by default escapes your template variables:
By default in Django, every template automatically escapes the output of every variable tag. Specifically, these five characters are escaped ...
but it won't strip the javascript away for you (it will just render it unusable), you need to do that manually with a template tag:
Strip javascript code before rendering in django templates
On the other hand, safe_mode on markdown strips any HTML in the text with [HTML REMOVED] as you've seen.
So removing safe should be enough to make it safe,

rendering of textfield and charfield chomps out extra whitespace (Django/Python)

I've noticed that my template is rendering my model.CharField and model.TextField without any excess whitespace.
For example, if I enter data such as...
This is a test
to see what happens.
The rendered object field will appear as...
This is a test to see what happens.
Is this an intentional feature of Django or have I missed some filter or parameter somewhere?
I've checked the field itself with some debug code (print object.field) and it does contains the extra whitespace, so the problem is in the rendering side.
How can I allow the user to enter paragraphs of data in TextFields? How can I preserve the whitespace that the user may have entered?

As you can see even in StackOverflow your spaces do not display, this is from the source of your question:
This is a test
to see what happens.
Will save in the database as:
This is a test\n\n\nto see what happens.
You have to problems when rendering as html:
Extra spaces between words are stripped on display by the browser, unless it is between <pre></pre> tags
Linebreaks will be rendered as plain text linebreaks, which do not display in the browser unless between <pre></pre> tags.
For spaces, you can use such a template filter to replace them with their html entity equivalent: .
To convert database linebreaks in HTML linebreaks, use linebreaksbr built-in filters. For example, if {{ foo }} is: test\nbar, then {{ foo|linebreaksbr }} will render: test<br />bar
Create a "templatetags" folder in some of your apps with an __init__.py file in it.
Save the snippet for example in someapp/templatetags/replace_tag.py
Load the template filter in the template as such {% load replace_tag %}
Combine replace and linebreaksbr as such: {{ foo|linebreaksbr|replace:" "," " }}
You can also make your own template filter that will process the text into the HTML you need. In any case, refer to the custom template filter documentation for complete information.