scraping Mohammed_Rafi songs

webscrapeOfSongs.js

/**
 * Get the URL for Rafi's song list that matches with your first letter of your name
 * Main songs list url: https://en.wikipedia.org/wiki/List_of_songs_recorded_by_Mohammed_Rafi
 * Make a request to get data from the given URL and find the link that is relavent for 
 * list of songs
 * 
 * @params startLetter - This is the letter to get the link for
 * @return URL for list of songs matches with first letter of your name
 */

let fetch = require("node-fetch");
var cheerio = require('cheerio');

async function getRafiMusicLink(startLetter) {
    let songLinksDocument = await fetch(`https://en.wikipedia.org/wiki/List_of_songs_recorded_by_Mohammed_Rafi`);
    let songLinksDocumentInTextFormat = await songLinksDocument.text();
    let listOfSongsTags = songLinksDocumentInTextFormat.match(/<a href="(\/wiki\/List_of_songs_recorded_by_Mohammed_Rafi_(\([A-Z]\)|\(B%E2%80%93C\)|\(D%E2%80%93F\)|\(H%E2%80%93I\)|\(P%E2%80%93R\)|\(U%E2%80%93Z\)))/gm);
    let textToMatch = `(${startLetter})`;
    console.log(`The letter to get the songs link is ${textToMatch}`);
    if (["B", "C"].indexOf(startLetter) !== -1) {
        textToMatch = `(B%E2%80%93C)`;
    } else if (["D", "E", "F"].indexOf(startLetter) !== -1) {
        textToMatch = `(D%E2%80%93F)`;
    } else if (["H", "I"].indexOf(startLetter) !== -1) {
        textToMatch = `(H%E2%80%93I)`;
    } else if (["P", "Q", "R"].indexOf(startLetter) !== -1) {
        textToMatch = `(P%E2%80%93R)`;
    } else if (["U", "V", "W", "X", "Y", "Z"].indexOf(startLetter) !== -1) {
        textToMatch = `(U%E2%80%93Z)`;
    }
    console.log(`The letter to get the songs link is ${textToMatch}`);

    for (let urlText of listOfSongsTags) {
        if (urlText.indexOf(textToMatch) !== -1) {
            let url = urlText.match(/<a href="(.*)$/);
            return url ? `https://en.wikipedia.org${url[1]}` : null;
        }
    }
}

/**
 * Give the URL for list of songs get all songs that are listed in the URL
 *
 * Parse the data comes from the URL and create an array of song object like:
 * {"name": "Name of the song", "year": year, "movie": "Movie of the song"}
 *
 *
 * @return Array of songs
 */
async function getListOfSongs(songsURL) {
    console.log(`Getting songs for url ${songsURL}`);
    let songsDocument = await fetch(songsURL);
    let songsInTextFormat = await songsDocument.text();
    var $ = cheerio.load(songsInTextFormat);
    console.log("gettign songs....");
    let songsList = [];
    for (let songsLiEle of $('.mw-parser-output ul > li').toArray()) {
        let songLiStr = songsLiEle.children[0].data;
        if (songLiStr) {
            if (songLiStr[1] === process.argv[2]) {
                let matches = songLiStr.match(/([\w\d\s,.]*) \([\dA-Za-z,\s-/\.&]*\)\s?\-(\s?([\d\w\s\/?]*)?\s(\d{4})?)?"?/);
                // console.log(songLiStr);
                // console.log(matches);
                if (matches) {
                    songsList.push({name: matches[1], movie: matches[3], year: matches[4]});
                }
            }
        }
    }
    // // '<li>"Woh Aaj Apni Mehfil Mein Aayein Huye Hain (Solo - Ravi/Kamil Rashid) - Mehndi 1958"</li>'
    // let songsList = songsInTextFormat.match(/Woh Aaj Apni Mehfil Mein Aayein/gim);
    return songsList;
}

/**
 * Given list of songs print how many songs were sung in a given year
 * Output should print year - no.of songs
 * 
 * Print top year where Rafi has sung most no.of songs
 *
 */
function analyze(songs) {
    let summaryOfSongsData = {};
    songs.forEach(element => {
        if (summaryOfSongsData[element.year]) {
            summaryOfSongsData[element.year] += 1;
        } else {
            summaryOfSongsData[element.year] = 1;
        }
    });
    return summaryOfSongsData;
}

/**
 * Main function
 */
async function main() {
    let inputValue = process.argv[2];
    if (inputValue) {
        let songsURL = await getRafiMusicLink(inputValue);
        let songs = await getListOfSongs(songsURL);
        // console.table(songs);
        let summary = await analyze(songs);
        console.table(summary);
        let highestSungSongInfo = {count: 1};
        for(let sungYear in summary) {
            if(sungYear !== "undefined" && highestSungSongInfo.count && highestSungSongInfo.count < summary[sungYear]) {
                highestSungSongInfo.year = sungYear;
                highestSungSongInfo.count = summary[sungYear];
            }
        }
        console.log(`Year ${highestSungSongInfo.year} has highest of ${highestSungSongInfo.count}s sung by Rafi`);
    } else {
        console.warn(`Please specify the Alphabet you are searching for as command line argument`);
    }
}

main();