bootbox prompt select with options from database

I am using bootbox prompt with select. To build the option for the select you have to provide something like this:

inputOptions: [
                {
                    text: 'Ad inizio tabella',
                    value: '',
                },
                {
                    text: 'Choice One',
                    value: '1',
                },
                {
                    text: 'Choice Two',
                    value: '2',
                },
                {
                    text: 'Choice Three',
                    value: '3',
                }
                ]

I want to make the options variable fetching them from the database. So I built a function:

        $.getJSON( "get_fields.php", { wizard: wizard } ).done(function(data){fields_selected=data;});

that returns a JSON as expected:

[
    {
        "text":"Inserisci dopo Nome",
        "value":"Nome"
    },
    {
        "text":"Inserisci dopo cognome",
        "value":"cognome"
    }
]

To pass it to the bootbox function I tried to do:

var fields = '';
            $.getJSON( "get_fields.php", { wizard: wizard } ).done(function(data){fields_selected=data;});
bootbox.prompt({
            title: "Scegli dopo quale campo inserire il nuovo",
            inputType: 'select',
            inputOptions: fields,
            callback: function (result) {

but in both cases I get the following:

Uncaught Error: Error: prompt with select requires options

since fields remains empty. What am I missing to be able to inject the data coming from getJson?

Since $.getJSON is an AJAX call, your options won't exist until that resolves. jQuery AJAX functions are non-blocking, so you're creating a Bootbox prompt with an "empty" object.

The easiest fix is to create the prompt in the success callback of your AJAX function. Something like:

$.getJSON("get_fields.php")
    .done(function(data) {
        bootbox.prompt({
            title: 'Select an option',
            inputOptions: data,
            callback: function(result){
            
            }
      });
  });