I am trying to figure out how to pass a variable into a custom template function and so far I haven’t been able to figure out how to make it work. The idea is that I am going to have a template be passed in and I want to have it call a custom Jinja2 function. I need to pass down a variable to the custom function. This will run in a Celery job, but for the sake of this question, I have simplified the issue.

Something similar to:

import jinja2

def calling_function():
   var1 = "joe"
   environment = jinja2.Environment()
   func_dict = {
   "do_it": do_it
   }
   environment.globals.update(func_dict)
   output = environment.from_string("{{ do_it() }}").render()
   print(output)

def do_it():
    return "yes: %s" % (var1)


calling_function()

I get a Name error which makes sense because it is out of scope:
NameError: name ‘var1’ is not defined. Did you mean: ‘vars’?

If I put var1 outside of the scope:

import jinja2

var1 = ""

def calling_function():
   var1 = "joe"
   environment = jinja2.Environment()
   func_dict = {
   "do_it": do_it
   }
   environment.globals.update(func_dict)
   output = environment.from_string("{{ do_it() }}").render()
   print(output)

def do_it():
    return "yes: %s" % (var1)

output:
yes:

The script completes but var1 is still empty. I would like to be able to get a variable down to do_it without having to manipulate or have anything more than {{ do_it() }}. I don’t know if I need to pass the variable into the template and then pull it back out?