ca-apm-probe/lib/utils/common-utils.js

CA APM Node.js Agent monitors real-time health and performance of Node.js applications

/**
 * Copyright (c) 2016 CA. All rights reserved.
 *
 * This software and all information contained therein is confidential and proprietary and
 * shall not be duplicated, used, disclosed or disseminated in any way except as authorized
 * by the applicable license agreement, without the express written permission of CA. All
 * authorized reproductions must be marked with this language.
 *
 * EXCEPT AS SET FORTH IN THE APPLICABLE LICENSE AGREEMENT, TO THE EXTENT
 * PERMITTED BY APPLICABLE LAW, CA PROVIDES THIS SOFTWARE WITHOUT WARRANTY
 * OF ANY KIND, INCLUDING WITHOUT LIMITATION, ANY IMPLIED WARRANTIES OF
 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL CA BE
 * LIABLE TO THE END USER OR ANY THIRD PARTY FOR ANY LOSS OR DAMAGE, DIRECT OR
 * INDIRECT, FROM THE USE OF THIS SOFTWARE, INCLUDING WITHOUT LIMITATION, LOST
 * PROFITS, BUSINESS INTERRUPTION, GOODWILL, OR LOST DATA, EVEN IF CA IS
 * EXPRESSLY ADVISED OF SUCH LOSS OR DAMAGE.
 */

'use strict';

var path = require('path');
const RESOURCE_METRIC_NODE = 'Node.js Runtime';
const RESOURCE_METRIC_PREFIX = RESOURCE_METRIC_NODE + ':';

function resolveEnv(name) {
    return name.replace(/\$\{(\w*)\}/g, function (match, p1, p2, p3, offset, string) {
        return process.env[p1];
    });
}

function findAppName() {
    var appNames = [];
    var appScriptFilename = process.mainModule.filename;
    var appPackage;
    try {
        appPackage = require(path.join(path.dirname(appScriptFilename), 'package.json'));
        appNames[0] = appPackage.name;
    } catch (error) {
    }

    // app name from application start script
    appNames[1] = path.basename(appScriptFilename, '.js');

    // app name from application start dir
    appNames[2] = path.dirname(appScriptFilename).split(path.sep).slice(-1)[0];

    for (var i = 0; i < appNames.length; i++) {
        if (appNames[i]) {
            return appNames[i];
        }
    }

    return null;
}

function isArray(v) {
    return (!!v) && (v.constructor === Array);
};

function isObject(v) {
    return (!!v) && (v.constructor === Object);
};

function merge(source,obj){
	for (var attrname in obj) {
        source[attrname] = obj[attrname];
    }
    return source;
};

function getResMetricPrefix() {
    var resMetricPrefix = RESOURCE_METRIC_PREFIX;
    var cluster = require('cluster');
    var workerNum = cluster.CAAPMPROBE_WORKERNUM;
    if (workerNum) {
        resMetricPrefix = RESOURCE_METRIC_NODE + '|worker' + workerNum + ':';
    }
    return resMetricPrefix;
}

// Reduce the fraction of a floating point number to a fixed quantity
// so that e.g. 0.6317000000000004 becomes 0.6317.
function fix(value) { return +(+value).toFixed(5); }

module.exports = {resolveEnv: resolveEnv, findAppName: findAppName, isArray: isArray, isObject: isObject, merge: merge, getResMetricPrefix: getResMetricPrefix, fix: fix};