Renames a collection of %COUNTRY_NAME%.ext files to a matching set of %ISO_CODE%.ext files.

renamer.js

/**
 * Renames a collection of %COUNTRY_NAME%.ext files to a matching set of
 * %ISO_CODE%.ext files.
 *
 * Uses the https://github.com/datasets/country-codes dataset for names
 * and ISO codes. Since it's CSV, I also used
 * https://github.com/Keyang/node-csvtojson to convert to JSON.
 *
 * V 0.0.2.
 */

const fs = require('fs')
const Converter = require('csvtojson').Converter
const COUNTRY_DATASET_DIR = './country-codes/data/country-codes.csv'

var converter = new Converter({})
var normalizedCountries = {}

// flatten out JSON data to a name: iso dictionary on parse end
converter.on('end_parsed', function(json) {
    normalizeJSONData(json, init)
})

// read CSV data
fs.createReadStream(COUNTRY_DATASET_DIR).pipe(converter)

// provide dir to work on as first arg
var targetDir = process.argv[2]

// provide a second dir as arg, or default to ./processed
var newDir = process.argv[3] || './processed/'


if (!targetDir) {
    console.log('give me a valid directory to work on!')
    return
}

// validate directories and add slashes at end
if (targetDir[targetDir.length - 1] !== '/') targetDir = targetDir + '/'
if (newDir[targetDir.length - 1] !== '/') newDir = newDir + '/'

/**
 * ================
 * Main init
 * ===============
 */
function init() {
    // see if newDir exists and create it if not
    fs.stat(newDir, function(err, stats) {
        if (stats && stats.isDirectory()) {
            batchRename() // Do rename now.
            return
        }

        // otherwise, init rename after creating dir thru callback
        fs.mkdir(newDir, function(err) {
            if (err) throw err

            batchRename() // Or now.
        })
    })
}

/**
 * NOTE: use read/write streams to make copies of existing files,
 * fs.rename moves the actual file
 */
function batchRename() {
    console.log('renaming...')

    fs.readdir(targetDir, function(err, flagFiles) {
        if (err) throw err

        flagFiles.map(function(flagName) {
            var newName

            // ignore pesky .DS_Store files
            if (flagName == '.DS_Store') return;

            // rename file
            newName = renameFile(flagName)

            // streams, baby
            fs.createReadStream(targetDir + flagName)
                .pipe(fs.createWriteStream(newDir + newName))
                .on('error', console.error)
        })
    })

    console.log('renaming complete!')
}

/**
 * Splits filename into name and extension; if name in list of
 * normalized countries (a dictionary of names and ISO3166-1 codes),
 * return that code, with extension. Otherwise, return filename.
 *
 * @param  {String} filename i.e. ''
 * @return {[type]}          [description]
 */
function renameFile(filename) {
    var strSplit = filename.split('.');
    var name = strSplit[0]
    var ext = '.' + strSplit[1]

    if (normalizedCountries[name]) {
        return normalizedCountries[name] + ext
    }

    return filename
}


/**
 * Extracts data from country info relevant to renaming files.
 * Init renaming thru callback
 *
 * @param  {Array} json        converted CSV data
 * @param  {Function} callback callback init() function
 * @return {undefined}
 */
function normalizeJSONData(json, callback) {

    json.map(function(country) {

        var name = slugifyName(country['name'])
        var iso = country['ISO3166-1-Alpha-2'].toLowerCase()

        normalizedCountries[name] = iso;
    })

    // init
    callback()
}

/**
 * Slugify name.
 *
 * @param  {String} name Full name with spaces, dots, ampersands, weird letters
 * @return {String}      slug
 */
function slugifyName(name) {
    // yeah this should be done using regexp
    return name.split('').map(function(char) {
        if (char == ' ') return '_'
        if (char == '.') return ''
        if (char == '&') return 'and'
        if (['Å', 'ã', 'â', 'à', 'á'].indexOf(char) >= 0) return 'a'
        if (['Ê', 'è', 'ȇ', 'é'].indexOf(char) >= 0) return 'e'

        // at least a little bit of regexp
        return char.replace(/[A-Z]/g, function(match) {
            return match.toLowerCase()
        })
    }).join('')
}