scratch-resources/bin/build-www-json

#!/usr/bin/env node

/*
    Generates json file defining the localized URLS for www. Assumes that
    files will be hosted on the scratch-resources bucket within a www folder.
    The key is based on the path to the file, for example the catch.pdf file 
    with the cards folder would generate: 

    '''
    {
        "en": {
            "cards.catchLink" : "//scratch-resources.s3.amazonaws.com/www/cards/catch.pdf"
        },
        "es": {
            "cards.catchLink" : "//scratch-resources.s3.amazonaws.com/www/cards/es/catch.pdf"
        },
        "sv": {
            "cards.catchLink" : "//scratch-resources.s3.amazonaws.com/www/cards/sv/catch.pdf"
        }
        ... etc ...
    }
    '''
*/

var fs = require('fs');
var path = require('path');
var url = require('url');
var merge = require('lodash.merge');

// -----------------------------------------------------------------------------
// Utility function
// -----------------------------------------------------------------------------

const allFilesSync = (dir, fileList = []) => {
    fs.readdirSync(dir).forEach(file => {
        const filePath = path.join(dir, file);
        if (!/\.DS*/.test(file)) {
            fileList.push(
                fs.statSync(filePath).isDirectory() ?
                {
                    [file]: allFilesSync(filePath)
                } :
                file
            );
        }
    });
    return fileList;
};

const fileId = (dir, file) => {
    return dir + '.' + path.parse(file).name + 'Link';
};

const bucketPath = (resource, locale, file) => {
    const bucketRoot = 'https://resources.scratch.mit.edu/www/';
    return url.resolve(bucketRoot, path.join(resource, locale, file));
};

const localeURL = (resource, locale, file) => {
    return {[fileId(resource, file)]: bucketPath(resource, locale, file)};
};

const parseFileList = (dirData, data = {}) => {
    // first level of data is the resource, e.g. 'cards', 'guides', etc.
    dirData.forEach(resData => {
        for (var resId in resData) {
            var locales = resData[resId];
            locales.forEach(localeData => { // eslint-disable-line no-loop-func
                for (var locale in localeData) {
                    var localeFiles = localeData[locale];
                    var localeMap = {};
                    localeFiles.forEach(f => { // eslint-disable-line no-loop-func
                        merge(localeMap, localeURL(resId, locale, f));
                    });
                    merge(data, {[locale]: localeMap});
                }
            });
        }
    });
    return data;
};

var writeJsonFile = function (outputDir, data) {
    var fileName = path.join(outputDir, 'localized-urls.json');
    fs.writeFileSync(fileName, JSON.stringify(data), 'utf8');
};

// -----------------------------------------------------------------------------
// Main script
// -----------------------------------------------------------------------------

var args = process.argv.slice(2);

if (!args.length) {
    process.stdout.write('An input directory of resources, and a target output directory must be specified.\n');
    process.exit(1);
}

var inputsDir = path.resolve(process.cwd(), args.shift());

try {
    fs.accessSync(inputsDir, fs.F_OK);
} catch (err) {
    process.stdout.write('Fatal error: No input directory.\n');
    process.exit(1);
}

if (!args.length) {
    process.stdout.write('A destination directory must be specified.\n');
    process.exit(1);
}
var outputDir = path.resolve(process.cwd(), args[0]);
try {
    fs.accessSync(outputDir, fs.F_OK);
} catch (err) {
    // Doesn't exist - create it.
    fs.mkdirSync(outputDir);
}

var allFiles = allFilesSync(inputsDir);
var output = parseFileList(allFiles);
writeJsonFile(outputDir, output);