How to implement in-app-purchase using Cordova plugin?

Question

Please tell me the way to implement in-app-purchase using Cordova plugin.

I'm developing Android application using Cordova. There are some in-app-purchase plugins but I decide to use Cordova Purchase Plugin.

I did some setups along README.md of In-App Purchase for PhoneGap / Cordova iOS and Android. As a result, I could call the Plugin using Demo of the Purchase Plugin for Cordova with my little modification. (See the following, it is a portion of code.)

app.initStore = function() {

if (!window.store) {
    log('Store not available');
    return;
}

// Enable maximum logging level
store.verbosity = store.DEBUG;

// Enable remote receipt validation
//    store.validator = "https://api.fovea.cc:1982/check-purchase";

// Inform the store of your products
log('registerProducts');
store.register({
    id:    'myProductA',
    alias: 'myProductA',
    type:   store.CONSUMABLE
});

// When any product gets updated, refresh the HTML.
store.when("product").updated(function (p) {
    console.info("app.renderIAP is called");
    app.renderIAP(p);
});

// Log all errors
store.error(function(error) {
    log('ERROR ' + error.code + ': ' + error.message);
});

// When purchase of an extra life is approved,
// deliver it... by displaying logs in the console.
store.when("myProductA").approved(function (order) {
    log("You got a ProductA");
    order.finish();
});

// When the store is ready (i.e. all products are loaded and in their "final"
// state), we hide the "loading" indicator.
//
// Note that the "ready" function will be called immediately if the store
// is already ready.
store.ready(function() {
    var el = document.getElementById("loading-indicator");
    console.info(el + "ready is called")
    if (el)
        el.style.display = 'none';
});

// When store is ready, activate the "refresh" button;
store.ready(function() {
    var el = document.getElementById('refresh-button');
    console.info(el + "ready is called and refresh-button show?");
    if (el) {
        el.style.display = 'block';
        el.onclick = function(ev) {
            store.refresh();
        };
    }
});

// Refresh the store.
//
// This will contact the server to check all registered products
// validity and ownership status.
//
// It's fine to do this only at application startup, as it could be
// pretty expensive.
log('refresh');
store.refresh();
};

It did not show 'Store not available' that is shown when plugin is not available, show 'registerProducts', and 'refresh.' (*Of course I added 'myProductA' to in-app Products on Google Play Developer Console.)

But I noticed that the below function is not called.

store.when("product").updated(function (p)

And also I couldn't understand what the parameter should fill in it, so I commented out the below. (*I did remove the comment out, but it still not working.)

store.validator = "https://api.fovea.cc:1982/check-purchase";

I guess those things make something wrong. I'm not sure what is stack on me, so my question is not clearly. I want some clues to solve it... or I shouldn't implement in-app-purchase using Cordova plugin?

Please give me your hand.

(I'm not fluent in English, so I'm sorry for any confusion.)