Add preferences service API for products (#20869)

app/channels.go

@@ -226,6 +226,10 @@ func NewChannels(s *Server, services map[ServiceKey]any) (*Channels, error) {
 
 	services[UserKey] = &App{ch: ch}
 
+	services[PreferencesKey] = &preferencesServiceWrapper{
+		app: &App{ch: ch},
+	}
+
 	return ch, nil
 }
 

app/preference.go

@@ -9,8 +9,29 @@ import (
 	"net/http"
 
 	"github.com/mattermost/mattermost-server/v6/model"
+	"github.com/mattermost/mattermost-server/v6/product"
 )
 
+// Ensure preferences service wrapper implements `product.PreferencesService`
+var _ product.PreferencesService = (*preferencesServiceWrapper)(nil)
+
+// preferencesServiceWrapper provides an implementation of `product.PreferencesService` for use by products.
+type preferencesServiceWrapper struct {
+	app AppIface
+}
+
+func (w *preferencesServiceWrapper) GetPreferencesForUser(userID string) (model.Preferences, *model.AppError) {
+	return w.app.GetPreferencesForUser(userID)
+}
+
+func (w *preferencesServiceWrapper) UpdatePreferencesForUser(userID string, preferences model.Preferences) *model.AppError {
+	return w.app.UpdatePreferences(userID, preferences)
+}
+
+func (w *preferencesServiceWrapper) DeletePreferencesForUser(userID string, preferences model.Preferences) *model.AppError {
+	return w.app.DeletePreferences(userID, preferences)
+}
+
 func (a *App) GetPreferencesForUser(userID string) (model.Preferences, *model.AppError) {
 	preferences, err := a.Srv().Store.Preference().GetAll(userID)
 	if err != nil {

app/server.go

@@ -103,6 +103,7 @@ const (
 	KVStoreKey       ServiceKey = "kvstore"
 	StoreKey         ServiceKey = "storekey"
 	SystemKey        ServiceKey = "systemkey"
+	PreferencesKey   ServiceKey = "preferenceskey"
 )
 
 type Server struct {

product/api.go

@@ -179,3 +179,12 @@ type StoreService interface {
 type SystemService interface {
 	GetDiagnosticId() string
 }
+
+// PreferencesService is the API for accessing the Preferences service APIs.
+//
+// The service shall be registered via app.PreferencesKey service key.
+type PreferencesService interface {
+	GetPreferencesForUser(userID string) (model.Preferences, *model.AppError)
+	UpdatePreferencesForUser(userID string, preferences model.Preferences) *model.AppError
+	DeletePreferencesForUser(userID string, preferences model.Preferences) *model.AppError
+}