Cache variable in server code

[javier]

Hello everyone!
This is my second post. I’m been working on anvil for like one week and there are a few things that i can’t find in docs or in the forum.

Currently i have an application that call an api when it start. I want to cache the response so when the same user (or other) use the app, the time will be fast.
I tried:

response = None

@anvil.server.callable
def getData():

  url = "api/my_url"

  global response
  if response:
    return response
  else:
    response = anvil.http.request(url, json=True)
    return response

The code above does not work. It seems to call the api everytime.
Also tried with session storage but it’s not what i want. ( in a extreme case it would work)

I want a way to store the api response in my server code.

Thank you all!

[stucork]

I think this might be the link in the docs that should explain the behaviour you’re experiencing

Anvil Docs | Server Code

Persistent server modules is the search term here.

Here’s a linked post that might also answer the question.

Question when updating global variables in server module

The problem is that the server code is reloaded every time you make a call to the server and all the globals are lost… unless you check the “keep server running” option, in which case the interpreter is not restarted at every call. But it still restarts once in a while, so you can’t rely on it. Globals on the client side are reliable, because the interpreter starts when the app loads and they are kept until the browser is closed. What is your use case for the globals?

[mjmare]

In cases such as these I tend to stuff the data (the json in your case) in a data table.