[MM-48161] Change data types for collections and topics (#21634)

* Change data types for collections and topics

* Address suggestions

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/channels.go

@@ -78,10 +78,10 @@ type Channels struct {
 	postReminderMut  sync.Mutex
 	postReminderTask *model.ScheduledTask
 
-	// collectionTypes maps collection types array to the registering plugin
-	collectionTypes map[string][]string
-	// topicTypes maps topic types array to collection types
-	topicTypes                 map[string][]string
+	// collectionTypes maps from collection types to the registering plugin id
+	collectionTypes map[string]string
+	// topicTypes maps from topic types to collection types
+	topicTypes                 map[string]string
 	collectionAndTopicTypesMut sync.Mutex
 }
 
@@ -103,8 +103,8 @@ func NewChannels(s *Server, services map[ServiceKey]any) (*Channels, error) {
 		srv:             s,
 		imageProxy:      imageproxy.MakeImageProxy(s.platform, s.httpService, s.Log()),
 		uploadLockMap:   map[string]bool{},
-		collectionTypes: map[string][]string{},
-		topicTypes:      map[string][]string{},
+		collectionTypes: map[string]string{},
+		topicTypes:      map[string]string{},
 	}
 
 	// To get another service:

app/collection.go

@@ -8,7 +8,6 @@ import (
 
 	"github.com/mattermost/mattermost-server/v6/model"
 	"github.com/mattermost/mattermost-server/v6/shared/mlog"
-	"github.com/mattermost/mattermost-server/v6/utils"
 )
 
 func (a *App) registerCollectionAndTopic(pluginID, collectionType, topicType string) error {
@@ -17,29 +16,20 @@ func (a *App) registerCollectionAndTopic(pluginID, collectionType, topicType str
 	defer a.ch.collectionAndTopicTypesMut.Unlock()
 
 	// check if collectionType was already registered by other plugin
-	for existingPluginID, existingCollectionTypes := range a.ch.collectionTypes {
-		if existingPluginID != pluginID && utils.StringInSlice(collectionType, existingCollectionTypes) {
-			return model.NewAppError("registerCollectionAndTopic", "app.collection.add_collection.exists.app_error", nil, "", http.StatusBadRequest)
-		}
+	existingPluginID, ok := a.ch.collectionTypes[collectionType]
+	if ok && existingPluginID != pluginID {
+		return model.NewAppError("registerCollectionAndTopic", "app.collection.add_collection.exists.app_error", nil, "", http.StatusBadRequest)
 	}
 
 	// check if topicType was already registered to other collection
-	for existingCollectionType, existingTopicTypes := range a.ch.topicTypes {
-		if existingCollectionType != collectionType && utils.StringInSlice(topicType, existingTopicTypes) {
-			return model.NewAppError("registerCollectionAndTopic", "app.collection.add_topic.exists.app_error", nil, "", http.StatusBadRequest)
-		}
+	existingCollectionType, ok := a.ch.topicTypes[topicType]
+	if ok && existingCollectionType != collectionType {
+		return model.NewAppError("registerCollectionAndTopic", "app.collection.add_topic.exists.app_error", nil, "", http.StatusBadRequest)
 	}
 
-	a.ch.collectionTypes[pluginID] = appendIfUnique(a.ch.collectionTypes[pluginID], collectionType)
-	a.ch.topicTypes[collectionType] = appendIfUnique(a.ch.topicTypes[collectionType], topicType)
+	a.ch.collectionTypes[collectionType] = pluginID
+	a.ch.topicTypes[topicType] = collectionType
 
 	a.ch.srv.Log().Info("registered collection and topic type", mlog.String("plugin_id", pluginID), mlog.String("collection_type", collectionType), mlog.String("topic_type", topicType))
 	return nil
 }
-
-func appendIfUnique(slice []string, a string) []string {
-	if utils.StringInSlice(a, slice) {
-		return slice
-	}
-	return append(slice, a)
-}

app/plugin.go

@@ -486,10 +486,19 @@ func (a *App) DisablePlugin(id string) *model.AppError {
 }
 
 func (ch *Channels) disablePlugin(id string) *model.AppError {
-	for _, collectionType := range ch.collectionTypes[id] {
-		delete(ch.topicTypes, collectionType)
+	// find all collectionTypes registered by plugin
+	for collectionTypeToRemove, existingPluginId := range ch.collectionTypes {
+		if existingPluginId != id {
+			continue
+		}
+		// find all topicTypes for existing collectionType
+		for topicTypeToRemove, existingCollectionType := range ch.topicTypes {
+			if existingCollectionType == collectionTypeToRemove {
+				delete(ch.topicTypes, topicTypeToRemove)
+			}
+		}
+		delete(ch.collectionTypes, collectionTypeToRemove)
 	}
-	delete(ch.collectionTypes, id)
 
 	pluginsEnvironment := ch.GetPluginsEnvironment()
 	if pluginsEnvironment == nil {