extend tags instead of replacing

Author: ThomasKranitsas

src/services/challengeService.js

@@ -31,8 +31,7 @@ const challengePropertiesToOmitFromDynamo = [
   'submissionStartDate',
   'submissionEndDate',
   'type',
-  'track',
-  'tags'
+  'track'
 ]
 
 async function save (challenge) {
@@ -89,7 +88,7 @@ async function updateChallenge (challenge) {
       id: challenge.id,
       body: {
         doc: {
-          ..._.omit(challenge, ['created', 'createdBy', 'tags']),
+          ..._.omit(challenge, ['created', 'createdBy']),
           groups: _.filter(challenge.groups, g => _.toString(g).toLowerCase() !== 'null')
         }
       }

src/services/syncService.js

@@ -137,6 +137,7 @@ async function processChallenge (legacyId, challengeListing, challengeDetails) {
     ..._.omit(v5ChallengeFromAPI, ['prizeSets']),
     ..._.omit(v5ChallengeObjectFromV4, ommittedFields),
     prizeSets,
+    tags: _.filter(_.uniq(_.concat(_.get(v5ChallengeFromAPI, 'tags'), _.get(v5ChallengeObjectFromV4, 'tags'))), t => _.toLower(t) !== 'other'),
     ...additionalInformation
   }
   // logger.debug(`new V5 Object: ${JSON.stringify(updatedV5Object)}`)