How can I pass my context variables to a javascript file in Django?

I don't think it's possible this way. If you want to access some data provided by the view, you have to pass it to the js function.

Example

js file:

my_cool_js_function(some_param){
    // do some cool stuff
}

view

// some html code

my_cool_js_function({{param}})

hope this helps :)

I would also add because I ran into the error a few times that if the python variable is an object it will throw a syntax error unless you put it in quotes, in other words, within your template,

<script>
   var my_var = '{{ python_object|escapejs }}';
</script>

Furthermore, before putting that object in the context it is best to first serialize it to JSON, or you'll end up having to do string parsing. I found also that date objects needed to be converted to strings before this step.

import jsonpickle

context['python_object'] = jsonpickle.encode(python_object)

And finally, in the JS you can then iterate through the object properly and use the values as you probably would have in python by doing:

var my_var_parsed = jQuery.parseJSON(my_var);

There is now a more secure way to pass context to a javascript file using the built-in template tag json_script with an argument which would be the id set for the created element.

Use case would be:

{{ mydata|json_script:"mydata" }}

Then link your javascript file:

<script src="{% static 'myjavascriptfile.js' %}"></script>

the script tag would have to come after the template tag i'm guessing

Which can then be accessed in your javascript file like:

const mydata = JSON.parse(document.getElementById('mydata').textContent);

Sources

django 3.1 docs json_script

Another source with a proper explanation

In addition to Andrzej Bobak's answer, you can also generate a global variable in Javascript from your template. For example, your template might generate code like this:

<script>
   var my_chart = {{ the_chart }};
</script>

Your script could then refer to my_chart.