[MM-15811] Adds fallback mechanism for elasticsearch queries (#11065)

* [MM-15811] Adds fallback mechanism for elasticsearch queries

* Rename config helpers

app/channel.go

@@ -107,8 +107,7 @@ func (a *App) JoinDefaultChannels(teamId string, user *model.User, shouldBeAdmin
 		}
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			if err = a.indexUser(user); err != nil {
 				mlog.Error("Encountered error indexing user", mlog.String("user_id", user.Id), mlog.Err(err))
@@ -185,8 +184,7 @@ func (a *App) CreateChannelWithUser(channel *model.Channel, userId string) (*mod
 	message.Add("team_id", channel.TeamId)
 	a.Publish(message)
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			if err := a.indexUser(user); err != nil {
 				mlog.Error("Encountered error indexing user", mlog.String("user_id", user.Id), mlog.Err(err))
@@ -261,11 +259,10 @@ func (a *App) CreateChannel(channel *model.Channel, addMember bool) (*model.Chan
 		})
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
-		if sc.Type == "O" {
+	if a.IsESIndexingEnabled() {
+		if sc.Type == model.CHANNEL_OPEN {
 			a.Srv.Go(func() {
-				if err := esInterface.IndexChannel(sc); err != nil {
+				if err := a.Elasticsearch.IndexChannel(sc); err != nil {
 					mlog.Error("Encountered error indexing channel", mlog.String("channel_id", sc.Id), mlog.Err(err))
 				}
 			})
@@ -309,8 +306,7 @@ func (a *App) GetOrCreateDirectChannel(userId, otherUserId string) (*model.Chann
 				})
 			}
 
-			esInterface := a.Elasticsearch
-			if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+			if a.IsESIndexingEnabled() {
 				a.Srv.Go(func() {
 					for _, id := range []string{userId, otherUserId} {
 						if err := a.indexUserFromId(id); err != nil {
@@ -419,8 +415,7 @@ func (a *App) CreateGroupChannel(userIds []string, creatorId string) (*model.Cha
 	message.Add("teammate_ids", model.ArrayToJson(userIds))
 	a.Publish(message)
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			for _, id := range userIds {
 				if err := a.indexUserFromId(id); err != nil {
@@ -517,10 +512,9 @@ func (a *App) UpdateChannel(channel *model.Channel) (*model.Channel, *model.AppE
 	messageWs.Add("channel", channel.ToJson())
 	a.Publish(messageWs)
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing && channel.Type == "O" {
+	if a.IsESIndexingEnabled() && channel.Type == model.CHANNEL_OPEN {
 		a.Srv.Go(func() {
-			if err := esInterface.IndexChannel(channel); err != nil {
+			if err := a.Elasticsearch.IndexChannel(channel); err != nil {
 				mlog.Error("Encountered error indexing channel", mlog.String("channel_id", channel.Id), mlog.Err(err))
 			}
 		})
@@ -1003,8 +997,7 @@ func (a *App) AddChannelMember(userId string, channel *model.Channel, userReques
 		})
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			if err := a.indexUser(user); err != nil {
 				mlog.Error("Encountered error indexing user", mlog.String("user_id", user.Id), mlog.Err(err))
@@ -1413,8 +1406,7 @@ func (a *App) JoinChannel(channel *model.Channel, userId string) *model.AppError
 		})
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			if err := a.indexUser(user); err != nil {
 				mlog.Error("Encountered error indexing user", mlog.String("user_id", user.Id), mlog.Err(err))
@@ -1649,8 +1641,7 @@ func (a *App) removeUserFromChannel(userIdToRemove string, removerUserId string,
 		})
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			if err := a.indexUserFromId(userIdToRemove); err != nil {
 				mlog.Error("Encountered error indexing user", mlog.String("user_id", userIdToRemove), mlog.Err(err))
@@ -1745,36 +1736,50 @@ func (a *App) UpdateChannelLastViewedAt(channelIds []string, userId string) *mod
 	return nil
 }
 
-func (a *App) AutocompleteChannels(teamId string, term string) (*model.ChannelList, *model.AppError) {
-	includeDeleted := *a.Config().TeamSettings.ExperimentalViewArchivedChannels
-	term = strings.TrimSpace(term)
+func (a *App) esAutocompleteChannels(teamId, term string, includeDeleted bool) (*model.ChannelList, *model.AppError) {
+	channelIds, err := a.Elasticsearch.SearchChannels(teamId, term)
+	if err != nil {
+		return nil, err
+	}
 
-	esInterface := a.Elasticsearch
-	license := a.License()
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableAutocomplete && license != nil && *license.Features.Elasticsearch {
-		channelIds, err := a.Elasticsearch.SearchChannels(teamId, term)
+	channelList := model.ChannelList{}
+	if len(channelIds) > 0 {
+		channels, err := a.Srv.Store.Channel().GetChannelsByIds(channelIds)
 		if err != nil {
 			return nil, err
 		}
-
-		channelList := model.ChannelList{}
-		if len(channelIds) > 0 {
-			channels, err := a.Srv.Store.Channel().GetChannelsByIds(channelIds)
-			if err != nil {
-				return nil, err
-			}
-			for _, c := range channels {
-				if c.DeleteAt > 0 && !includeDeleted {
-					continue
-				}
-				channelList = append(channelList, c)
+		for _, c := range channels {
+			if c.DeleteAt > 0 && !includeDeleted {
+				continue
 			}
+			channelList = append(channelList, c)
 		}
-
-		return &channelList, nil
 	}
 
-	return a.Srv.Store.Channel().AutocompleteInTeam(teamId, term, includeDeleted)
+	return &channelList, nil
+}
+
+func (a *App) AutocompleteChannels(teamId string, term string) (*model.ChannelList, *model.AppError) {
+	includeDeleted := *a.Config().TeamSettings.ExperimentalViewArchivedChannels
+	var channelList *model.ChannelList
+	var err *model.AppError
+	term = strings.TrimSpace(term)
+
+	if a.IsESAutocompletionEnabled() {
+		channelList, err = a.esAutocompleteChannels(teamId, term, includeDeleted)
+		if err != nil {
+			mlog.Error("Encountered error on AutocompleteChannels through Elasticsearch. Falling back to default autocompletion.", mlog.Err(err))
+		}
+	}
+
+	if !a.IsESAutocompletionEnabled() || err != nil {
+		channelList, err = a.Srv.Store.Channel().AutocompleteInTeam(teamId, term, includeDeleted)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return channelList, nil
 }
 
 func (a *App) AutocompleteChannelsForSearch(teamId string, userId string, term string) (*model.ChannelList, *model.AppError) {
@@ -1927,8 +1932,7 @@ func (a *App) PermanentDeleteChannel(channel *model.Channel) *model.AppError {
 		return result.Err
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			for _, user := range channelUsers.Data.(map[string]*model.User) {
 				if err := a.indexUser(user); err != nil {
@@ -1936,9 +1940,9 @@ func (a *App) PermanentDeleteChannel(channel *model.Channel) *model.AppError {
 				}
 			}
 		})
-		if channel.Type == "O" {
+		if channel.Type == model.CHANNEL_OPEN {
 			a.Srv.Go(func() {
-				if err := esInterface.DeleteChannel(channel); err != nil {
+				if err := a.Elasticsearch.DeleteChannel(channel); err != nil {
 					mlog.Error("Encountered error deleting channel", mlog.String("channel_id", channel.Id), mlog.Err(err))
 				}
 			})

app/config.go

@@ -399,3 +399,19 @@ func (a *App) SaveConfig(newCfg *model.Config, sendConfigChangeClusterMessage bo
 
 	return nil
 }
+
+func (a *App) IsESIndexingEnabled() bool {
+	return a.Elasticsearch != nil && *a.Config().ElasticsearchSettings.EnableIndexing
+}
+
+func (a *App) IsESSearchEnabled() bool {
+	esInterface := a.Elasticsearch
+	license := a.License()
+	return esInterface != nil && *a.Config().ElasticsearchSettings.EnableSearching && license != nil && *license.Features.Elasticsearch
+}
+
+func (a *App) IsESAutocompletionEnabled() bool {
+	esInterface := a.Elasticsearch
+	license := a.License()
+	return esInterface != nil && *a.Config().ElasticsearchSettings.EnableAutocomplete && license != nil && *license.Features.Elasticsearch
+}

app/post.go

@@ -274,10 +274,9 @@ func (a *App) CreatePost(post *model.Post, channel *model.Channel, triggerWebhoo
 		})
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
-			if err = esInterface.IndexPost(rpost, channel.TeamId); err != nil {
+			if err = a.Elasticsearch.IndexPost(rpost, channel.TeamId); err != nil {
 				mlog.Error("Encountered error indexing post", mlog.String("post_id", post.Id), mlog.Err(err))
 			}
 		})
@@ -551,15 +550,14 @@ func (a *App) UpdatePost(post *model.Post, safeUpdate bool) (*model.Post, *model
 		})
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			rchannel := <-a.Srv.Store.Channel().GetForPost(rpost.Id)
 			if rchannel.Err != nil {
 				mlog.Error(fmt.Sprintf("Couldn't get channel %v for post %v for Elasticsearch indexing.", rpost.ChannelId, rpost.Id))
 				return
 			}
-			if err := esInterface.IndexPost(rpost, rchannel.Data.(*model.Channel).TeamId); err != nil {
+			if err := a.Elasticsearch.IndexPost(rpost, rchannel.Data.(*model.Channel).TeamId); err != nil {
 				mlog.Error("Encountered error indexing post", mlog.String("post_id", post.Id), mlog.Err(err))
 			}
 		})
@@ -708,10 +706,9 @@ func (a *App) DeletePost(postId, deleteByID string) (*model.Post, *model.AppErro
 		a.DeleteFlaggedPosts(post.Id)
 	})
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
-			if err := esInterface.DeletePost(post); err != nil {
+			if err := a.Elasticsearch.DeletePost(post); err != nil {
 				mlog.Error("Encountered error deleting post", mlog.String("post_id", post.Id), mlog.Err(err))
 			}
 		})
@@ -811,75 +808,82 @@ func (a *App) SearchPostsInTeam(teamId string, paramsList []*model.SearchParams)
 	})
 }
 
-func (a *App) SearchPostsInTeamForUser(terms string, userId string, teamId string, isOrSearch bool, includeDeletedChannels bool, timeZoneOffset int, page, perPage int) (*model.PostSearchResults, *model.AppError) {
-	paramsList := model.ParseSearchParams(strings.TrimSpace(terms), timeZoneOffset)
+func (a *App) esSearchPostsInTeamForUser(paramsList []*model.SearchParams, userId, teamId string, isOrSearch, includeDeletedChannels bool, page, perPage int) (*model.PostSearchResults, *model.AppError) {
+	finalParamsList := []*model.SearchParams{}
 	includeDeleted := includeDeletedChannels && *a.Config().TeamSettings.ExperimentalViewArchivedChannels
 
-	esInterface := a.Elasticsearch
-	license := a.License()
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableSearching && license != nil && *license.Features.Elasticsearch {
-		finalParamsList := []*model.SearchParams{}
-
-		for _, params := range paramsList {
-			params.OrTerms = isOrSearch
-			// Don't allow users to search for "*"
-			if params.Terms != "*" {
-				// Convert channel names to channel IDs
-				for idx, channelName := range params.InChannels {
-					channel, err := a.parseAndFetchChannelIdByNameFromInFilter(channelName, userId, teamId, includeDeletedChannels)
-					if err != nil {
-						mlog.Error(fmt.Sprint(err))
-						continue
-					}
-					params.InChannels[idx] = channel.Id
+	for _, params := range paramsList {
+		params.OrTerms = isOrSearch
+		// Don't allow users to search for "*"
+		if params.Terms != "*" {
+			// Convert channel names to channel IDs
+			for idx, channelName := range params.InChannels {
+				channel, err := a.parseAndFetchChannelIdByNameFromInFilter(channelName, userId, teamId, includeDeletedChannels)
+				if err != nil {
+					mlog.Error(fmt.Sprint(err))
+					continue
 				}
-
-				// Convert usernames to user IDs
-				for idx, username := range params.FromUsers {
-					if user, err := a.GetUserByUsername(username); err != nil {
-						mlog.Error(fmt.Sprint(err))
-					} else {
-						params.FromUsers[idx] = user.Id
-					}
-				}
-
-				finalParamsList = append(finalParamsList, params)
+				params.InChannels[idx] = channel.Id
 			}
-		}
 
-		// If the processed search params are empty, return empty search results.
-		if len(finalParamsList) == 0 {
-			return model.MakePostSearchResults(model.NewPostList(), nil), nil
-		}
+			// Convert usernames to user IDs
+			for idx, username := range params.FromUsers {
+				if user, err := a.GetUserByUsername(username); err != nil {
+					mlog.Error(fmt.Sprint(err))
+				} else {
+					params.FromUsers[idx] = user.Id
+				}
+			}
 
-		// We only allow the user to search in channels they are a member of.
-		userChannels, err := a.GetChannelsForUser(teamId, userId, includeDeleted)
-		if err != nil {
-			mlog.Error(fmt.Sprint(err))
-			return nil, err
+			finalParamsList = append(finalParamsList, params)
 		}
+	}
 
-		postIds, matches, err := a.Elasticsearch.SearchPosts(userChannels, finalParamsList, page, perPage)
+	// If the processed search params are empty, return empty search results.
+	if len(finalParamsList) == 0 {
+		return model.MakePostSearchResults(model.NewPostList(), nil), nil
+	}
+
+	// We only allow the user to search in channels they are a member of.
+	userChannels, err := a.GetChannelsForUser(teamId, userId, includeDeleted)
+	if err != nil {
+		mlog.Error(fmt.Sprint(err))
+		return nil, err
+	}
+
+	postIds, matches, err := a.Elasticsearch.SearchPosts(userChannels, finalParamsList, page, perPage)
+	if err != nil {
+		return nil, err
+	}
+
+	// Get the posts
+	postList := model.NewPostList()
+	if len(postIds) > 0 {
+		posts, err := a.Srv.Store.Post().GetPostsByIds(postIds)
 		if err != nil {
 			return nil, err
 		}
-
-		// Get the posts
-		postList := model.NewPostList()
-		if len(postIds) > 0 {
-			posts, err := a.Srv.Store.Post().GetPostsByIds(postIds)
-			if err != nil {
-				return nil, err
-			}
-			for _, p := range posts {
-				if p.DeleteAt == 0 {
-					postList.AddPost(p)
-					postList.AddOrder(p.Id)
-				}
+		for _, p := range posts {
+			if p.DeleteAt == 0 {
+				postList.AddPost(p)
+				postList.AddOrder(p.Id)
 			}
 		}
+	}
 
-		return model.MakePostSearchResults(postList, matches), nil
+	return model.MakePostSearchResults(postList, matches), nil
+}
+
+func (a *App) SearchPostsInTeamForUser(terms string, userId string, teamId string, isOrSearch bool, includeDeletedChannels bool, timeZoneOffset int, page, perPage int) (*model.PostSearchResults, *model.AppError) {
+	var postSearchResults *model.PostSearchResults
+	var err *model.AppError
+	paramsList := model.ParseSearchParams(strings.TrimSpace(terms), timeZoneOffset)
+
+	if a.IsESSearchEnabled() {
+		postSearchResults, err = a.esSearchPostsInTeamForUser(paramsList, userId, teamId, isOrSearch, includeDeletedChannels, page, perPage)
+		if err != nil {
+			mlog.Error("Encountered error on SearchPostsInTeamForUser through Elasticsearch. Falling back to default search.", mlog.Err(err))
+		}
 	}
 
 	if !*a.Config().ServiceSettings.EnablePostSearch {
@@ -891,24 +895,30 @@ func (a *App) SearchPostsInTeamForUser(terms string, userId string, teamId strin
 		return model.MakePostSearchResults(model.NewPostList(), nil), nil
 	}
 
-	posts, err := a.searchPostsInTeam(teamId, userId, paramsList, func(params *model.SearchParams) {
-		params.IncludeDeletedChannels = includeDeleted
-		params.OrTerms = isOrSearch
-		for idx, channelName := range params.InChannels {
-			if strings.HasPrefix(channelName, "@") {
-				channel, err := a.parseAndFetchChannelIdByNameFromInFilter(channelName, userId, teamId, includeDeletedChannels)
-				if err != nil {
-					mlog.Error(fmt.Sprint(err))
-					continue
+	if !a.IsESSearchEnabled() || err != nil {
+		includeDeleted := includeDeletedChannels && *a.Config().TeamSettings.ExperimentalViewArchivedChannels
+		posts, err := a.searchPostsInTeam(teamId, userId, paramsList, func(params *model.SearchParams) {
+			params.IncludeDeletedChannels = includeDeleted
+			params.OrTerms = isOrSearch
+			for idx, channelName := range params.InChannels {
+				if strings.HasPrefix(channelName, "@") {
+					channel, err := a.parseAndFetchChannelIdByNameFromInFilter(channelName, userId, teamId, includeDeletedChannels)
+					if err != nil {
+						mlog.Error(fmt.Sprint(err))
+						continue
+					}
+					params.InChannels[idx] = channel.Name
 				}
-				params.InChannels[idx] = channel.Name
 			}
+		})
+		if err != nil {
+			return nil, err
 		}
-	})
-	if err != nil {
-		return nil, err
+
+		postSearchResults = model.MakePostSearchResults(posts, nil)
 	}
-	return model.MakePostSearchResults(posts, nil), nil
+
+	return postSearchResults, nil
 }
 
 func (a *App) GetFileInfosForPostWithMigration(postId string) ([]*model.FileInfo, *model.AppError) {

app/user.go

@@ -280,8 +280,7 @@ func (a *App) createUserOrGuest(user *model.User, guest bool) (*model.User, *mod
 		})
 	}
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			if err := a.indexUser(user); err != nil {
 				mlog.Error("Encountered error indexing user", mlog.String("user_id", user.Id), mlog.Err(err))
@@ -1160,8 +1159,7 @@ func (a *App) UpdateUser(user *model.User, sendNotifications bool) (*model.User,
 
 	a.InvalidateCacheForUser(user.Id)
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			if err := a.indexUser(user); err != nil {
 				mlog.Error("Encountered error indexing user", mlog.String("user_id", user.Id), mlog.Err(err))
@@ -1516,8 +1514,7 @@ func (a *App) PermanentDeleteUser(user *model.User) *model.AppError {
 
 	mlog.Warn(fmt.Sprintf("Permanently deleted account %v id=%v", user.Email, user.Id), mlog.String("user_id", user.Id))
 
-	esInterface := a.Elasticsearch
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+	if a.IsESIndexingEnabled() {
 		a.Srv.Go(func() {
 			if err := a.Elasticsearch.DeleteUser(user); err != nil {
 				mlog.Error("Encountered error deleting user", mlog.String("user_id", user.Id), mlog.Err(err))
@@ -1709,35 +1706,25 @@ func (a *App) SearchUsersNotInChannel(teamId string, channelId string, term stri
 	return users, nil
 }
 
-func (a *App) SearchUsersInTeam(teamId string, term string, options *model.UserSearchOptions) ([]*model.User, *model.AppError) {
-	var result store.StoreResult
-
-	term = strings.TrimSpace(term)
-
-	esInterface := a.Elasticsearch
-	license := a.License()
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableAutocomplete && license != nil && *license.Features.Elasticsearch {
-		listOfAllowedChannels, err := a.GetViewUsersRestrictionsForTeam(a.Session.UserId, teamId)
-		if err != nil {
-			return nil, err
-		}
-		if listOfAllowedChannels != nil && len(listOfAllowedChannels) == 0 {
-			return []*model.User{}, nil
-		}
-
-		usersIds, err := a.Elasticsearch.SearchUsersInTeam(teamId, listOfAllowedChannels, term, options)
-		if err != nil {
-			return nil, err
-		}
-
-		result = <-a.Srv.Store.User().GetProfileByIds(usersIds, false, nil)
-	} else {
-		result = <-a.Srv.Store.User().Search(teamId, term, options)
+func (a *App) esSearchUsersInTeam(teamId, term string, options *model.UserSearchOptions) ([]*model.User, *model.AppError) {
+	listOfAllowedChannels, err := a.GetViewUsersRestrictionsForTeam(a.Session.UserId, teamId)
+	if err != nil {
+		return nil, err
+	}
+	if listOfAllowedChannels != nil && len(listOfAllowedChannels) == 0 {
+		return []*model.User{}, nil
 	}
 
+	usersIds, err := a.Elasticsearch.SearchUsersInTeam(teamId, listOfAllowedChannels, term, options)
+	if err != nil {
+		return nil, err
+	}
+
+	result := <-a.Srv.Store.User().GetProfileByIds(usersIds, false, nil)
 	if result.Err != nil {
 		return nil, result.Err
 	}
+
 	users := result.Data.([]*model.User)
 
 	for _, user := range users {
@@ -1747,6 +1734,34 @@ func (a *App) SearchUsersInTeam(teamId string, term string, options *model.UserS
 	return users, nil
 }
 
+func (a *App) SearchUsersInTeam(teamId, term string, options *model.UserSearchOptions) ([]*model.User, *model.AppError) {
+	var users []*model.User
+	var err *model.AppError
+	term = strings.TrimSpace(term)
+
+	if a.IsESAutocompletionEnabled() {
+		users, err = a.esSearchUsersInTeam(teamId, term, options)
+		if err != nil {
+			mlog.Error("Encountered error on SearchUsersInTeam through Elasticsearch. Falling back to default search.", mlog.Err(err))
+		}
+	}
+
+	if !a.IsESAutocompletionEnabled() || err != nil {
+		result := <-a.Srv.Store.User().Search(teamId, term, options)
+		if result.Err != nil {
+			return nil, result.Err
+		}
+
+		users = result.Data.([]*model.User)
+
+		for _, user := range users {
+			a.SanitizeProfile(user, options.IsAdmin)
+		}
+	}
+
+	return users, nil
+}
+
 func (a *App) SearchUsersNotInTeam(notInTeamId string, term string, options *model.UserSearchOptions) ([]*model.User, *model.AppError) {
 	term = strings.TrimSpace(term)
 	result := <-a.Srv.Store.User().SearchNotInTeam(notInTeamId, term, options)
@@ -1777,38 +1792,26 @@ func (a *App) SearchUsersWithoutTeam(term string, options *model.UserSearchOptio
 	return users, nil
 }
 
-func (a *App) AutocompleteUsersInChannel(teamId string, channelId string, term string, options *model.UserSearchOptions) (*model.UserAutocompleteInChannel, *model.AppError) {
-	var uchan, nuchan store.StoreChannel
-
-	term = strings.TrimSpace(term)
-
-	esInterface := a.Elasticsearch
-	license := a.License()
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableAutocomplete && license != nil && *license.Features.Elasticsearch {
-		listOfAllowedChannels, err := a.getListOfAllowedChannelsForTeam(teamId, options.ViewRestrictions)
-		if err != nil {
-			return nil, err
-		}
-		if len(listOfAllowedChannels) == 0 {
-			return &model.UserAutocompleteInChannel{}, nil
-		}
-		uchanIds := []string{}
-		nuchanIds := []string{}
-		if !strings.Contains(strings.Join(listOfAllowedChannels, "."), channelId) {
-			nuchanIds, err = a.Elasticsearch.SearchUsersInTeam(teamId, listOfAllowedChannels, term, options)
-		} else {
-			uchanIds, nuchanIds, err = a.Elasticsearch.SearchUsersInChannel(teamId, channelId, listOfAllowedChannels, term, options)
-		}
-		if err != nil {
-			return nil, err
-		}
-		uchan = a.Srv.Store.User().GetProfileByIds(uchanIds, false, nil)
-		nuchan = a.Srv.Store.User().GetProfileByIds(nuchanIds, false, nil)
-	} else {
-		uchan = a.Srv.Store.User().SearchInChannel(channelId, term, options)
-		nuchan = a.Srv.Store.User().SearchNotInChannel(teamId, channelId, term, options)
+func (a *App) esAutocompleteUsersInChannel(teamId, channelId, term string, options *model.UserSearchOptions) (*model.UserAutocompleteInChannel, *model.AppError) {
+	listOfAllowedChannels, err := a.getListOfAllowedChannelsForTeam(teamId, options.ViewRestrictions)
+	if err != nil {
+		return nil, err
 	}
-
+	if len(listOfAllowedChannels) == 0 {
+		return &model.UserAutocompleteInChannel{}, nil
+	}
+	uchanIds := []string{}
+	nuchanIds := []string{}
+	if !strings.Contains(strings.Join(listOfAllowedChannels, "."), channelId) {
+		nuchanIds, err = a.Elasticsearch.SearchUsersInTeam(teamId, listOfAllowedChannels, term, options)
+	} else {
+		uchanIds, nuchanIds, err = a.Elasticsearch.SearchUsersInChannel(teamId, channelId, listOfAllowedChannels, term, options)
+	}
+	if err != nil {
+		return nil, err
+	}
+	uchan := a.Srv.Store.User().GetProfileByIds(uchanIds, false, nil)
+	nuchan := a.Srv.Store.User().GetProfileByIds(nuchanIds, false, nil)
 	autocomplete := &model.UserAutocompleteInChannel{}
 
 	result := <-uchan
@@ -1838,47 +1841,112 @@ func (a *App) AutocompleteUsersInChannel(teamId string, channelId string, term s
 	return autocomplete, nil
 }
 
-func (a *App) AutocompleteUsersInTeam(teamId string, term string, options *model.UserSearchOptions) (*model.UserAutocompleteInTeam, *model.AppError) {
-	autocomplete := &model.UserAutocompleteInTeam{}
-	var result store.StoreResult
-
+func (a *App) AutocompleteUsersInChannel(teamId string, channelId string, term string, options *model.UserSearchOptions) (*model.UserAutocompleteInChannel, *model.AppError) {
+	var autocomplete *model.UserAutocompleteInChannel
+	var err *model.AppError
 	term = strings.TrimSpace(term)
 
-	esInterface := a.Elasticsearch
-	license := a.License()
-	if esInterface != nil && *a.Config().ElasticsearchSettings.EnableAutocomplete && license != nil && *license.Features.Elasticsearch {
-		listOfAllowedChannels, err := a.getListOfAllowedChannelsForTeam(teamId, options.ViewRestrictions)
+	if a.IsESAutocompletionEnabled() {
+		autocomplete, err = a.esAutocompleteUsersInChannel(teamId, channelId, term, options)
 		if err != nil {
-			return nil, err
+			mlog.Error("Encountered error on AutocompleteUsersInChannel through Elasticsearch. Falling back to default autocompletion.", mlog.Err(err))
 		}
-		if len(listOfAllowedChannels) == 0 {
-			return &model.UserAutocompleteInTeam{}, nil
-		}
-
-		usersIds, err := a.Elasticsearch.SearchUsersInTeam(teamId, listOfAllowedChannels, term, options)
-		if err != nil {
-			return nil, err
-		}
-
-		result = <-a.Srv.Store.User().GetProfileByIds(usersIds, false, nil)
-	} else {
-		result = <-a.Srv.Store.User().Search(teamId, term, options)
 	}
 
+	if !a.IsESAutocompletionEnabled() || err != nil {
+		autocomplete = &model.UserAutocompleteInChannel{}
+		uchan := a.Srv.Store.User().SearchInChannel(channelId, term, options)
+		nuchan := a.Srv.Store.User().SearchNotInChannel(teamId, channelId, term, options)
+
+		result := <-uchan
+		if result.Err != nil {
+			return nil, result.Err
+		}
+		users := result.Data.([]*model.User)
+
+		for _, user := range users {
+			a.SanitizeProfile(user, options.IsAdmin)
+		}
+
+		autocomplete.InChannel = users
+
+		result = <-nuchan
+		if result.Err != nil {
+			return nil, result.Err
+		}
+		users = result.Data.([]*model.User)
+
+		for _, user := range users {
+			a.SanitizeProfile(user, options.IsAdmin)
+		}
+
+		autocomplete.OutOfChannel = users
+	}
+
+	return autocomplete, nil
+}
+
+func (a *App) esAutocompleteUsersInTeam(teamId, term string, options *model.UserSearchOptions) (*model.UserAutocompleteInTeam, *model.AppError) {
+	listOfAllowedChannels, err := a.getListOfAllowedChannelsForTeam(teamId, options.ViewRestrictions)
+	if err != nil {
+		return nil, err
+	}
+	if len(listOfAllowedChannels) == 0 {
+		return &model.UserAutocompleteInTeam{}, nil
+	}
+
+	usersIds, err := a.Elasticsearch.SearchUsersInTeam(teamId, listOfAllowedChannels, term, options)
+	if err != nil {
+		return nil, err
+	}
+
+	result := <-a.Srv.Store.User().GetProfileByIds(usersIds, false, nil)
 	if result.Err != nil {
 		return nil, result.Err
 	}
-	users := result.Data.([]*model.User)
 
+	users := result.Data.([]*model.User)
 	for _, user := range users {
 		a.SanitizeProfile(user, options.IsAdmin)
 	}
 
+	autocomplete := &model.UserAutocompleteInTeam{}
 	autocomplete.InTeam = users
 
 	return autocomplete, nil
 }
 
+func (a *App) AutocompleteUsersInTeam(teamId string, term string, options *model.UserSearchOptions) (*model.UserAutocompleteInTeam, *model.AppError) {
+	var autocomplete *model.UserAutocompleteInTeam
+	var err *model.AppError
+
+	term = strings.TrimSpace(term)
+
+	if a.IsESAutocompletionEnabled() {
+		autocomplete, err = a.esAutocompleteUsersInTeam(teamId, term, options)
+		if err != nil {
+			mlog.Error("Encountered error on AutocompleteUsersInTeam through Elasticsearch. Falling back to default autocompletion.", mlog.Err(err))
+		}
+	}
+
+	if !a.IsESAutocompletionEnabled() || err != nil {
+		autocomplete = &model.UserAutocompleteInTeam{}
+		result := <-a.Srv.Store.User().Search(teamId, term, options)
+		if result.Err != nil {
+			return nil, result.Err
+		}
+
+		users := result.Data.([]*model.User)
+		for _, user := range users {
+			a.SanitizeProfile(user, options.IsAdmin)
+		}
+
+		autocomplete.InTeam = users
+	}
+
+	return autocomplete, nil
+}
+
 func (a *App) UpdateOAuthUserAttrs(userData io.Reader, user *model.User, provider einterfaces.OauthProvider, service string) *model.AppError {
 	oauthUser := provider.GetUserFromJson(userData)
 	if oauthUser == nil {
@@ -1922,8 +1990,7 @@ func (a *App) UpdateOAuthUserAttrs(userData io.Reader, user *model.User, provide
 		user = users.New
 		a.InvalidateCacheForUser(user.Id)
 
-		esInterface := a.Elasticsearch
-		if esInterface != nil && *a.Config().ElasticsearchSettings.EnableIndexing {
+		if a.IsESIndexingEnabled() {
 			a.Srv.Go(func() {
 				if err := a.indexUser(user); err != nil {
 					mlog.Error("Encountered error indexing user", mlog.String("user_id", user.Id), mlog.Err(err))