tools.js

var fs = require('fs');
var path = require('path');
var crypto = require('crypto');
var gutil = require('gulp-util');

module.exports = ( function () {


    var filepathRegex = /.*?(?:\'|\")([a-z0-9_\-\/\.]+?\.[a-z]{2,4})(?:(?:\?|\#)[^'"]*?|)(?:\'|\").*?/ig;
    var fileMap = {};

    // Taken from gulp-rev: https://github.com/sindresorhus/gulp-rev
    var md5 = function (str) {
        return crypto.createHash('md5').update(str, 'utf8').digest('hex');
    };

    // Taken from gulp-rev: https://github.com/sindresorhus/gulp-rev
    var revFile = function (filePath, options) {

        if (fileMap[filePath]) 
            return fileMap[filePath];

        var contents = fs.readFileSync(filePath).toString();

        var hash = md5(contents).slice(0, options.hashLength);
        var ext = path.extname(filePath);
        var filename = path.basename(filePath, ext) + '-' + hash + ext;
        var filePathReved = path.join(path.dirname(filePath), filename);

        fileMap[filePath] = filePathReved;
        return fileMap[filePath];

    };

    var revReferencesInFile = function (file, options) {

        var replaceMap = {};
        var rootDir = options.rootDir || path.dirname(file.path);

        gutil.log('gulp-rev-all:', 'Finding references in [', file.path, ']');
        // Create a map of file references and their proper revisioned name
        var contents = String(file.contents);
        var result;

        var fullpath = '';

        while (result = filepathRegex.exec(contents)) {

            // Skip if we've already resolved this reference
            if (typeof replaceMap[result[1]] !== 'undefined') continue;
            replaceMap[result[1]] = false;

            // In the case where the referenced file is relative to the base path
            if (rootDir) {
                fullpath = path.join(rootDir, result[1]);
                if (fs.existsSync(fullpath)) {
                    replaceMap[result[1]] = path.dirname(result[1]) + '/' + path.basename(revFile(fullpath, options));
                    gutil.log('gulp-rev-all:', 'Found root reference [', result[1], '] -> [', replaceMap[result[1]], ']');
                    continue;
                }
            }

            // In the case where the file referenced is relative to the file being processed
            fullpath = path.join(file.base, result[1]);
            if (fs.existsSync(fullpath)) {
                replaceMap[result[1]] = path.dirname(result[1]) + '/' + path.basename(revFile(fullpath, options));
                gutil.log('gulp-rev-all:', 'Found relative reference [', result[1], '] -> [', replaceMap[result[1]], ']');
                continue;
            }

        }

        for (var key in replaceMap) {
            if (!replaceMap[key]) continue;
            contents = contents.replace(key, replaceMap[key]); 
        }

        file.contents = new Buffer(contents); // Update file contents with new reved references

    };

    return {
        revFile: revFile,
        revReferencesInFile: revReferencesInFile
    };

}());