ca-apm-probe/lib/probes/redis.js

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

/**
 * Copyright (c) 2015 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.
 */
var agent = require('../agent');
var logger = require("../logger.js");
var proxy = require('../proxy');
var targetModule = new Object;
module.exports = function(redis) {

    targetModule.redis = redis;

    logger.info('redis: instrument()');
    var redis = this.targetModule;

    proxy.before(targetModule.redis.RedisClient.prototype, 'internal_send_command',
        function(obj, args, storage) {
            if (agent.paused) return;
            var command = args[0];
            if(!command) return;
            var input = command.callback;
            input = [input];
            if (obj.connection_options) {
                if (obj.connection_options.host) {
                    var hostName = obj.connection_options.host;
                }
                if (obj.connection_options.port) {
                    var port = obj.connection_options.port;
                }
            }
            var eventNameFormatted = 'redis.' + command.command;
            var ctx = storage.get('ctx');
            ctx = agent.asynchEventStart(ctx, eventNameFormatted, {
                hostname: hostName,
                port: port
            });
            storage.set('ctx', ctx);
            var callbackIndex = 0;
            if (typeof input[callbackIndex] === 'function') {
                proxy.callback(input, callbackIndex, handle, afterHandle);
            } else {
                if (typeof input[callbackIndex] !== 'function') {
                    input.push(function() {});
                    callbackIndex += 1;
                }
                proxy.callback(input, callbackIndex, handle, afterHandle);
            }
            command.callback = input[callbackIndex];
            function handle(obj, args, storage) {
                var errorObject = agent.checkAndSetErrorObject(args, 'redisError');
                if (ctx != null) {
                    logger.debug('%s[%d %d %d]: callback', eventNameFormatted, ctx.txid, ctx.lane, ctx.evtid);
                    ctx = agent.asynchEventDone(ctx, eventNameFormatted, null, errorObject);
                    storage.set('ctx', ctx);
                }
            }
            function afterHandle(obj, args) {
                if (ctx != null) agent.asynchEventFinish(ctx);
            }
        });
};


function getMethodsWithProbes() {
    var mt = new Object;
    mt[0] = 'redis#send_command';
    return mt;
}

function instrument(redis) {
    targetModule.redis = redis;
}

module.exports.instrument = instrument.bind(module.exports);

module.exports.getMethodsWithProbes = getMethodsWithProbes;