pyodide button demo (SOF-6821)

[VsevolodX]

No description provided.

[VsevolodX]

The main problem is that when reading globals from pyodide instance, we get only default ones. Like name, loader etc, but not the ones that we added in python. Although the data is present inside pyodide and can be printed from python to the console (stdout)

[pranabdas]

@VsevolodX we need result.toJs() to convert python dictionary into JS map. Then we can use .get(key) to extract values. Note result holds only functional return from python code.

[VsevolodX]

Basically this means we can only get the result of one run of code (the return of the last called function to be exact). A bit limiting, but in this particular usage, it's sufficient.

[pranabdas]

Looks like globals behave differently when we try to move data both ways. It does work any one way. If we do not pass any globals with runPythonAsync, pyodide.globals.toJs().get(key) does work. But do we really need it to both ways? I guess we have other options:

1. Pass data from JS to pyodide via globals, and get as functional return the other way
2. Do not pass any data to pyodide, write functions with required data as args, do not call any functions there. Then access function names in JS via globals and call with args

pyodide.runPython(`
def sq(x):
    return x * x
`);
const sq = pyodide.globals.toJs().get("sq");
console.log(sq(5));

Note that whenever there is python dictionary, we need .toJs() to transform into JS map.