Given list of Google Play packages, find all similar apps (without repetitions) and their attributes

find_similar_google_play_apps.js

#!/usr/bin/env node
var gplay = require('./google-play-scraper'); // download from https://github.com/facundoolano/google-play-scraper
// input
var main_packages = [
'com.google.android.gm',
'com.google.android.apps.inbox',
]; // packages to look for similar apps

// Outputs unique list of similar apps to given apps
output_sep=";";

var results;
var main_toProcess = main_packages.length;
var packages = main_packages;
var toProcess = 0;

// from https://stackoverflow.com/questions/11688692/most-elegant-way-to-create-a-list-of-unique-items-in-javascript
function unique(arr) {
    var u = {}, a = [];
    for(var i = 0, l = arr.length; i < l; ++i){
        if(!u.hasOwnProperty(arr[i])) {
            a.push(arr[i]);
            u[arr[i]] = 1;
        }
    }
    return a;
}

function extract(app) {
    var result = "";
    result += app.title + output_sep;
    result += '' + app.score + output_sep;
    result += '' + app.reviews + output_sep;
    result += '' + app.minInstalls + output_sep;
    result += '' + app.offersIAP + output_sep;
    result += '' + app.androidVersionText + output_sep;
    result += '' + app.url;
    console.log(result);
    toProcess--;
    if (toProcess == 0) {
        process.exit()
    }
}

function processPackages() {
    var packagesUnique = unique(packages);
    toProcess = packagesUnique.length;
    console.log("Title;Score;Reviews;Min installs;IAPs;Android version;URL");
    for (pkg of packagesUnique) {
        gplay.app({appId: pkg}).then(extract, console.log);
    }
}

function findSimilar(list) {
    for (sim of list) {
        packages.push(sim.appId);
    }
    main_toProcess--;
    if (main_toProcess == 0) {
        processPackages()
    }
}

for (pkg of main_packages) {
    gplay.similar({appId: pkg}).then(findSimilar);
}