gulp-autoload/index.js

'use strict';

var fs = require("fs");

// Inject coffeescript
require("coffee-script/register");

/**
 * Used to autoload all .js or .coffee files from a given subfolder.
 * Expects an object argument like this:
 * {
 *     path:         <string> [optional] The path where your gulp scripts are saved
 *     moduleConfig: <object> [optional] An object that is passed to your gulp scripts
 *     debug:        <bool>   [optional] Enables debug logging
 * }
 * @param config
 */
function autoloader(config) {
    var logger = getLogger(config);

    logger.log("Initializing");

    // Apply a fallback in case the user did not provide a path
    logger.logPrefixed(["var", "config::path"], "Checking if var is defined");
    if (typeof config["path"] === typeof undefined) {
        logger.logPrefixed(["var", "config::path"], "Var is undefined. Applying fallback");
        config.path = "./gulp.d";
    }
    logger.logPrefixed(["var", "config::path"], "Value present");

    // Check if config.path is a folder
    logger.logPrefixed(["fs"], "Checking if " + config.path + " is an actual folder");
    var pathStats = fs.statSync(config.path);
    if (!pathStats.isDirectory()) {
        logger.logPrefixed(["fs"], config.path + " is not a folder!");
        return 1;
    }
    logger.logPrefixed(["fs"], "Check successful.");

    // Open folder
    logger.logPrefixed(["fs"], "Opening " + config.path + "...");

    var files;
    try {
        files = fs.readdirSync(config.path);
    } catch(e) {
        logger.logPrefixed(["fs"], "Error: It seems like " + config.path + " is not a folder!");
        return 1;
    }

    // Load modules
    logger.logPrefixed(["fs"], "Walking " + config.path + "...");
    for(var i in files) {
        //noinspection JSUnfilteredForInLoop
        var file = files[i];
        var realpath = process.cwd() + "/" + config.path + '/' + file;

        logger.logPrefixed(["fs", file], "Evaluating file...");

        // Check if the file is JS/CS
        if(file.indexOf(".js") === -1 && file.indexOf(".coffee") === -1) {
            logger.logPrefixed(["fs", file], "Skipping! This is neither javascript nor coffee-script.");
            return 2;
        }

        // Require the module
        logger.logPrefixed(["fs", file], "Calling require()...");

        var module;
        try {
            module = require(realpath);
        } catch(e) {
            logger.logPrefixed(["mod", file], "Error during require() call:");
            console.log(e);
            console.log();
            return 3;
        }

        // If the module is not returning a function we're done
        logger.logPrefixed(["fs", file], "Checking if require() returned a function...");
        if(typeof module !== "function") {
            logger.logPrefixed(["fs", file], "require() did not return a function. Assuming the presence of side-effects.");
            logger.logPrefixed(["fs", file, "+O"], "Module loaded.");
            continue;
        }

        // Else call the function and apply the moduleConfig
        //noinspection JSUnresolvedVariable
        logger.logPrefixed(["fs", file], "require() returned a function! Calling it...");
        module(config.moduleConfig);
        logger.logPrefixed(["fs", file, "+F"], "Module loaded.");
    }

    return 0;
}

/**
 * Small getter
 * @param config
 * @returns {Function}
 */
function getLogger(config) {
    return {
        /**
         * Log a message to the console.
         * Prefixes msg with [AutoLoader].
         *
         * @param msg
         * @param spacing
         */
        log: function(msg, spacing) {
            if(config["debug"] !== true) {
                return;
            }

            if(typeof spacing === typeof undefined) {
                spacing = false;
            }

            console.log("[AutoLoader]" + (spacing ? " " : "") + msg)
        },

        /**
         * Log a message to the console.
         * Works like log() but allows more prefixes
         *
         * @param prefixes
         * @param msg
         */
        logPrefixed: function(prefixes, msg) {
            if(config["debug"] !== true) {
                return;
            }

            if(typeof prefixes !== typeof []) {
                prefixes = [];
            }

            var s = "[AutoLoader]";
            for(var i = 0; i < prefixes.length; i++) {
                s += "[" + prefixes[i] + "]";
            }

            s += " " + msg;

            console.log(s);
        }
    }
}

/**
 * Export module to nodejs
 * @param config
 */
module.exports = function(config) {
    var exitCode = autoloader(config);

    if(typeof exitCode !== "number" || exitCode > 0) {
        var logger = getLogger(config);

        logger.log("Error. Autoloader exited with statuscode " + exitCode);
        logger.log("This should *not* happen!");
        logger.log("Please check your configuration.");
    }
};