Return Python function onto Chrome console

Question

I am trying to return a function from Python onto google chrome console using eel in Python.

This is the current code I have:

Python

import eel

eel.init('web')


print("Start")



@eel.expose
def my_python_function(a, b):
    print(a, b)


eel.start('index.html')

HTML

<!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <meta charset="utf-8">
    <title>Tutorial</title>


    <script type="text/javascript" src="/eel.js"></script>
    <script>
      console.log('Calling Python...');
      eel.my_python_function(1, 2);

    </script>




  </head>
  <body>
<p>test</p>
  </body>
</html>

In the HTML js script, eel.my_python_function(1,2) will print out onto the cmd.

I have tried the following to try get the Python function to be outputted onto the Chrome console.

Take 1

<script type="text/javascript" src="/eel.js"></script>
<script>
  console.log('Calling Python...');
  a = eel.my_python_function(1, 2);
  console.log(a);

</script>

this gave me this output on google chrome:

ƒ (callback = null) {
            if(callback != null) {
                eel._call_return_callbacks[call.call] = callback;
            } else {
                return new Promise(function(resolve) {

and this is my Try 2

<script type="text/javascript" src="/eel.js"></script>
<script>
  console.log('Calling Python...');
  a = eel.my_python_function(1, 2);
  console.log(a());

</script>

Have adjusted the console.log(a); to console.log(a());

The output was promise

The real output should be 1 2

score 1 · Answer 1 · answered Apr 24 '20 at 21:45

Your python function does not return anything try to use

Python:

@eel.expose
def my_python_function(a, b):
    return a+ b

Js:

console.log('Calling Python...');
eel.my_python_function(1, 2)().then((r) => {
    console.log(r);
});

I have encountered the same issue and is the only solution I find

score 0 · Answer 2 · answered Sep 16 '19 at 18:07

0

https://github.com/ChrisKnott/Eel#callbacks

In Javascript, the language doesn't allow us to block while we wait for a callback, except by using await from inside an async function. So the equivalent code from the Javascript side would be:

// Inside a function marked 'async' we can use the 'await' keyword.
async function run() {

  // The first call returns the function and the second actually execute it
  let a = await eel.my_python_function()(1,2);
  // Must prefix call with 'await', otherwise it's the same syntax

  console.log("Got this from Python: " + a);
}

run();

Read more: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/await

answered Sep 16 '19 at 18:07

rafaelcastrocouto

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returns me this error code here: ` return_val = _exposed_functions[message['name']](*message['args']) TypeError: my_python_function() missing 2 required positional arguments: 'a' and 'b' 2019-09-16T18:13:31Z failed with TypeError ` – Sep 16 '19 at 18:13
Did you try `let a = await eel.my_python_function(1,2)();` ? – rafaelcastrocouto Sep 16 '19 at 23:49

Return Python function onto Chrome console

2 Answers2