ca-apm-probe/lib/probes/graphql.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 path = require('path');
var agent = require('../agent');
var proxy = require('../proxy');

var logger = require("../logger.js");
var config = require('../configdata').getConfigData();
var showGraphQLQuery = config.graphql.showGraphQLQuery;

var targetModule = new Object;

module.exports = function (graphql) {

  targetModule.graphql = graphql;
  targetModule.Execution = findExecution(targetModule.graphql, require);
  targetModule.methodMap = getMethodsWithProbes();
  var methodMap = targetModule.methodMap;
  if (methodMap[0] == "skip_instrument") {
    return;
  }
  logger.info('Loading graphql probe');
  proxy.before(targetModule.Execution, 'execute', queryHook);
};

function queryHook(obj, args, storage) {
  var req = args[0];
  if(!req.document){
    return;
  }
  var operationDefinition = null

  req.document.definitions.forEach(element => {
    if(element.kind == "OperationDefinition"){
      operationDefinition = element;
    }
  });

  var operation = operationDefinition.operation;
  var query = null;

  operationDefinition.selectionSet.selections.forEach(element => {
    if(!query){
      query = element.name.value;
    } else {
      query += ',' + element.name.value;
    }
  });

  var ctx = storage.get('ctx') || req.__CA_ctx;

  var queryString = query;
  if(ctx != null && showGraphQLQuery){
    queryString = storage.get('gqlQuery');
    queryString = JSON.stringify(queryString).replace(/\\n/g, '');
  }

  if(ctx != null){
    if(!agent.graphQLUrl){
      agent.graphQLUrl = ctx.args.url;
    }
    ctx.args.url = ctx.args.url + "/" + operation + "/" + query;
    ctx.args.hdrs[0]="GraphQL";
  }

  var evtName = 'graphql.execute';
  var gqlCtx = agent.asynchEventStart(ctx, evtName, {
    operation: operation,
    query: queryString,
    tracePreviousCtx: true
  });

  if(ctx != null){
    ctx.gqlCtx = gqlCtx;
    gqlCtx.asyncCall = true;
    gqlCtx.fragmentEntryPoint = ctx.args.url;
  }
  storage.set('ctx', gqlCtx);
}

function findExecution(parent, require) {
  var cache = require.cache;
  for (var key in cache) {
    var candidate = cache[key];
    if (candidate.exports !== parent) {
      continue;
    }

    var dirname = path.dirname(candidate.filename);
    var filename = path.join(dirname, 'execution', 'execute.js');
    try {
      return require(filename);
    } catch (e) {
      return null;
    }
  }
  return null;
}

function getMethodsWithProbes() {
  if (!targetModule.methodMap) {
    var mt = new Object;
    mt[0] = 'graphql#execute';
    targetModule.methodMap = mt;
  }
  return targetModule.methodMap;
}

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

module.exports.getMethodsWithProbes = getMethodsWithProbes;

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