[Python] How do you pass a variable from javascript to python (oTree) or django?

I have some created some variables in Javascript to tracker how long an individual holds a button. I would like to pass these variables within a class in python (oTree) to store the data.

So, suppose the Javascript code is as follows:

let javascriptvariable = 0;


This javascriptvariable will be updated as the user clicks the button, so let's say the final value is javascriptvariable = 100. The python code is below.

class DisplayCharacteristics2(Page):
form_model = 'player'
pythonvariable = javascriptvariable


@staticmethod
def vars_for_template(player: Player):
return {
"var1": player.var1,
}


I tried created an empty variable, but I get an error which says something like javascript can't "add" to a null variable. I also tried using django in combination with javascript (see below), but javascript cannot add to a null variable. I tried to let it equal to zero first, but then I only get data points of 0.

let javascriptvariable = `{{ pythonvariable|safe }}`


Any leads will be appreciated! Thanks in advance.

Continue reading...