From bde180ddb1d9bd4da88db4f0cee49f45aaed0454 Mon Sep 17 00:00:00 2001
From: Chris Roberson <chrisronline@gmail.com>
Date: Mon, 30 Sep 2019 18:11:07 -0400
Subject: [PATCH] Backport 42876 (#46986)

---
 .../usage/classes/__tests__/collector_set.js  | 20 ++++++++++--
 src/server/usage/classes/collector_set.js     | 31 ++++++++++---------
 2 files changed, 34 insertions(+), 17 deletions(-)

diff --git a/src/server/usage/classes/__tests__/collector_set.js b/src/server/usage/classes/__tests__/collector_set.js
index 51688f986f3f..b08be68f6e54 100644
--- a/src/server/usage/classes/__tests__/collector_set.js
+++ b/src/server/usage/classes/__tests__/collector_set.js
@@ -71,6 +71,24 @@ describe('CollectorSet', () => {
         result: { passTest: 1000 }
       }]);
     });
+
+    it('should gracefully handle a collector fetch method throwing an error', async () => {
+      const mockCallCluster = () => Promise.resolve({ passTest: 1000 });
+      const collectors = new CollectorSet(server);
+      collectors.register(new Collector(server, {
+        type: 'MY_TEST_COLLECTOR',
+        fetch: () => new Promise((_resolve, reject) => reject())
+      }));
+
+      let result;
+      try {
+        result = await collectors.bulkFetch(mockCallCluster);
+      } catch (err) {
+        // Do nothing
+      }
+      // This must return an empty object instead of null/undefined
+      expect(result).to.eql([]);
+    });
   });
 
   describe('toApiFieldNames', () => {
@@ -162,5 +180,3 @@ describe('CollectorSet', () => {
     });
   });
 });
-
-
diff --git a/src/server/usage/classes/collector_set.js b/src/server/usage/classes/collector_set.js
index 9e4789eed2dc..5a86992f0af7 100644
--- a/src/server/usage/classes/collector_set.js
+++ b/src/server/usage/classes/collector_set.js
@@ -18,7 +18,6 @@
  */
 
 import { snakeCase } from 'lodash';
-import Promise from 'bluebird';
 import { getCollectorLogger } from '../lib';
 import { Collector } from './collector';
 import { UsageCollector } from './usage_collector';
@@ -31,7 +30,6 @@ let _waitingForAllCollectorsTimestamp = null;
  * and optionally, how to combine it into a unified payload for bulk upload.
  */
 export class CollectorSet {
-
   /*
    * @param {Object} server - server object
    * @param {Array} collectors to initialize, usually as a result of filtering another CollectorSet instance
@@ -46,7 +44,7 @@ export class CollectorSet {
      */
     this.makeStatsCollector = options => new Collector(server, options);
     this.makeUsageCollector = options => new UsageCollector(server, options);
-    this._makeCollectorSetFromArray = collectorsArray => new CollectorSet(server, collectorsArray);
+    this._makeCollectorSetFromArray = collectorsArray => new CollectorSet(server, collectorsArray, config);
 
     this._maximumWaitTimeForAllCollectorsInS = config ? config.get('stats.maximumWaitTimeForAllCollectorsInS') : 60;
   }
@@ -115,24 +113,26 @@ export class CollectorSet {
    * Call a bunch of fetch methods and then do them in bulk
    * @param {CollectorSet} collectorSet - a set of collectors to fetch. Default to all registered collectors
    */
-  bulkFetch(callCluster, collectorSet = this) {
+  async bulkFetch(callCluster, collectorSet = this) {
     if (!(collectorSet instanceof CollectorSet)) {
       throw new Error(`bulkFetch method given bad collectorSet parameter: ` + typeof collectorSet);
     }
 
-    const fetchPromises = collectorSet.map(collector => {
-      const collectorType = collector.type;
-      this._log.debug(`Fetching data from ${collectorType} collector`);
-      return Promise.props({
-        type: collectorType,
-        result: collector.fetchInternal(callCluster) // use the wrapper for fetch, kicks in error checking
-      })
-        .catch(err => {
-          this._log.warn(err);
-          this._log.warn(`Unable to fetch data from ${collectorType} collector`);
+    const responses = [];
+    await collectorSet.asyncEach(async collector => {
+      this._log.debug(`Fetching data from ${collector.type} collector`);
+      try {
+        responses.push({
+          type: collector.type,
+          result: await collector.fetchInternal(callCluster)
         });
+      }
+      catch (err) {
+        this._log.warn(err);
+        this._log.warn(`Unable to fetch data from ${collector.type} collector`);
+      }
     });
-    return Promise.all(fetchPromises);
+    return responses;
   }
 
   /*
@@ -150,6 +150,7 @@ export class CollectorSet {
 
   // convert an array of fetched stats results into key/object
   toObject(statsData) {
+    if (!statsData) return {};
     return statsData.reduce((accumulatedStats, { type, result }) => {
       return {
         ...accumulatedStats,