concierge-bot/core/config.js

/**
    * Manages the loading and saving of configuration data.
    *
    * Written By:
    *              Matthew Knox
    *
    * License:
    *              MIT License. All code unless otherwise specified is
    *              Copyright (c) Matthew Knox and Contributors 2015.
    */

var fs = require('fs'),
    path = require('path'),
    modConfig = null,
    modConfigFile = 'config.json',
    sysConfig = null,
    sysConfigZones = ['output', 'disabled', 'update', 'admin', 'i18n', 'firstRun', 'loopback'],
    sysConfigFile = 'config.json';

var loadConfig = function (location) {
    try {
        var data = fs.readFileSync(location, 'utf8');
        return JSON.parse(data);
    }
    catch (e) {
        console.debug($$`No or invalid configuration file found at "${location}".`);
        return {};
    }
};

var saveIndividualConfig = function (location, data) {
    fs.writeFileSync(location, JSON.stringify(data, function(key, value) {
        if (sysConfigZones.includes(key) && Object.keys(value).length === 0) {
            return void (0); // deliberate use of undefined, will cause property to be deleted.
        }
        return value;
    }, 4), 'utf8');
};

exports.saveModuleConfig = function(mod) {
    try {
        var m = modConfig[mod];
        var exists = false;
        try {
            fs.statSync(m.location);
            exists = true;
        } catch (e) { } // fs.existsSync is deprecated for some unknown reason

        // don't bother saving if there is no config to overwrite and no config to save
        if (Object.keys(m).length !== 0 || exists) {
            saveIndividualConfig(m.location, m.data);
        }
        delete modConfig[mod];
        return true;
    } catch (e) {
        console.error($$`An error occured while saving the configuration file.`);
        console.critical(e);
        return false;
    }
};

exports.saveSystemConfig = function () {
    try {
        saveIndividualConfig(sysConfigFile, sysConfig);
        sysConfig = null;
        return true;
    } catch (e) {
        console.error($$`An error occured while saving the configuration file.`);
        console.critical(e);
        return false;
    }
};

exports.getConfig = function (m) {
    var isSystem = sysConfigZones.includes(m);

    if (!sysConfig) {
        sysConfig = loadConfig(sysConfigFile);
    }

    if (!isSystem && !sysConfig[m]) {
        return {};
    }
    else if (!sysConfig[m]) {
        sysConfig[m] = {};
    }

    if (!isSystem) {
        console.warn($$`Configuration data for module ${m} stored in deprecated location.`);
        var cfg = sysConfig[m];
        delete sysConfig[m];
        return cfg;
    }
    return sysConfig[m];
};

exports.getLoadedModuleConfig = function (moduleName) {
    if (!modConfig) {
        modConfig = {};
    }

    if (!modConfig[moduleName]) {
        let location = path.join(global.__modulesPath, moduleName, modConfigFile);
        modConfig[moduleName] = {
            location: location,
            data: loadConfig(location)
        };
    }
    return modConfig[moduleName];
};

exports.loadModuleConfig = function (module, location, ignoreCache) {
    if (!modConfig) {
        modConfig = {};
    }

    if (modConfig[module.name] && !ignoreCache) {
        return modConfig[module.name];
    }

    var loc = path.join(location, modConfigFile),
        configData = loadConfig(loc),
        deprecatedDataA = exports.getConfig(module.name),
        deprecatedDataB = exports.getConfig(module.name + '.js');
    for (var name in deprecatedDataA) {
        configData[name] = deprecatedDataA[name];
    }
    for (var name in deprecatedDataB) {
        configData[name] = deprecatedDataB[name];
    }

    modConfig[module.name] = {
        location: path.join(location, modConfigFile),
        data: configData
    };
    return configData;
};

exports.loadOutputConfig = function (outputName) {
    var config = exports.getConfig(sysConfigZones[0]);
    if (!config[outputName]) {
        config[outputName] = {};
    }
    return config[outputName];
};