A script to make concurrent network requests!

concurrent-http-requests-full.js

const fetch = require('node-fetch');

const queryString = (year, goals, page) => {
    const rootUrl = 'https://jsonmock.hackerrank.com';
    const queryString = `/api/football_matches?year=${year}&team1goals=${goals}&team2goals=${goals}&page=${page}`;
    return rootUrl + queryString;
}

async function getNumOfGamesFromPage(year, goals, page) {
    const response = await fetch(queryString(year, goals, page))
        .catch(err => console.log("get error " + err.message));

    const json = await response.json();

    if (page === 0) {
        return [json.data.length, json.total_pages];
    } else {
        return json.data.length;
    }
}

async function getTiesCountByNumberOfGoals(year, goals) {
    const [gamesOnFirstPage, numberOfPages] = await getNumOfGamesFromPage(year, goals, 0);

    const pageArray = Array.from(Array(numberOfPages).keys()).filter((e) => e !== 0);

    return Promise.all(
        [
            gamesOnFirstPage, 
            ...pageArray.map(page => getNumOfGamesFromPage(year, goals, page))
        ])
    ).then(data => data.reduce((x, y) => x + y, 0) || 0);
}

async function getNumDraws(year) {
    const arrayOfScores = Array.from(Array(11).keys());

    return Promise.all(arrayOfScores.map(item => getTiesCountByNumberOfGoals(year, item)))
        .then(drawsCountForEachScore => {
            return drawsCountForEachScore.reduce((x, y) => x + y, 0);
        })
}

async function main() {
    const year = 2011;
    const result = await getNumDraws(year);
    console.log(`In ${year}, a total of ${result} games ended in a draw`);
}

main();