feat: Skip syncing on start if flag set (#485)

* Skip syncing on start if flag set

* Skip sync specifically

* remove need to use project

* Return early

* add comment

* Add test and fix existing one

Author: tvarney13

cmd/cliflags/flags.go

@@ -17,6 +17,7 @@ const (
 	PortFlag         = "port"
 	ProjectFlag      = "project"
 	RoleFlag         = "role"
+	SyncOnceFlag     = "sync-once"
 
 	AccessTokenFlagDescription = "LaunchDarkly access token with write-level access"
 	AnalyticsOptOutDescription = "Opt out of analytics tracking"
@@ -27,6 +28,7 @@ const (
 	OutputFlagDescription      = "Command response output format in either JSON or plain text"
 	PortFlagDescription        = "Port for the dev server to run on"
 	ProjectFlagDescription     = "Default project key"
+	SyncOnceFlagDescription    = "Only sync new projects. Existing projects will not be resynced on startup"
 )
 
 func AllFlagsHelp() map[string]string {
@@ -40,5 +42,6 @@ func AllFlagsHelp() map[string]string {
 		OutputFlag:       OutputFlagDescription,
 		PortFlag:         PortFlagDescription,
 		ProjectFlag:      ProjectFlagDescription,
+		SyncOnceFlag:     SyncOnceFlagDescription,
 	}
 }

cmd/config/testdata/help.golden

@@ -10,6 +10,7 @@ Supported settings:
 - `output`: Command response output format in either JSON or plain text
 - `port`: Port for the dev server to run on
 - `project`: Default project key
+- `sync-once`: Only sync new projects. Existing projects will not be resynced on startup
 
 Usage:
   ldcli config [flags]

cmd/dev_server/start_server.go

@@ -43,6 +43,9 @@ func NewStartServerCmd(client dev_server.Client) *cobra.Command {
 	cmd.Flags().String(OverrideFlag, "", `Stringified JSON representation of flag overrides ex. {"flagName": true, "stringFlagName": "test" }`)
 	_ = viper.BindPFlag(OverrideFlag, cmd.Flags().Lookup(OverrideFlag))
 
+	cmd.Flags().Bool(cliflags.SyncOnceFlag, false, cliflags.SyncOnceFlagDescription)
+	_ = viper.BindPFlag(cliflags.SyncOnceFlag, cmd.Flags().Lookup(cliflags.SyncOnceFlag))
+
 	return cmd
 }
 
@@ -58,6 +61,7 @@ func startServer(client dev_server.Client) func(*cobra.Command, []string) error
 				Enabled:    true,
 				ProjectKey: viper.GetString(cliflags.ProjectFlag),
 				EnvKey:     viper.GetString(SourceEnvironmentFlag),
+				SyncOnce:   viper.GetBool(cliflags.SyncOnceFlag),
 			}
 			if viper.IsSet(ContextFlag) {
 				var c ldcontext.Context

internal/dev_server/model/sync.go

@@ -18,6 +18,7 @@ type InitialProjectSettings struct {
 	EnvKey     string
 	Context    *ldcontext.Context   `json:"context,omitempty"`
 	Overrides  map[string]FlagValue `json:"overrides,omitempty"`
+	SyncOnce   bool
 }
 
 func CreateOrSyncProject(ctx context.Context, settings InitialProjectSettings) error {
@@ -29,17 +30,23 @@ func CreateOrSyncProject(ctx context.Context, settings InitialProjectSettings) e
 	var project Project
 	project, createError := CreateProject(ctx, settings.ProjectKey, settings.EnvKey, settings.Context)
 	if createError != nil {
-		if errors.Is(createError, ErrAlreadyExists) {
-			log.Printf("Project [%s] exists, refreshing data", settings.ProjectKey)
-			var updateErr error
-			project, updateErr = UpdateProject(ctx, settings.ProjectKey, settings.Context, &settings.EnvKey)
-			if updateErr != nil {
-				return updateErr
-			}
-
-		} else {
+		if !errors.Is(createError, ErrAlreadyExists) {
 			return createError
 		}
+
+		// If set, don't resync and don't apply overrides because whatever you have locally
+		// is already set up with what you want.
+		if settings.SyncOnce {
+			log.Printf("Project [%s] exists, but --sync-once flag is set, skipping refresh", settings.ProjectKey)
+			return nil
+		}
+
+		log.Printf("Project [%s] exists, refreshing data", settings.ProjectKey)
+		var updateErr error
+		project, updateErr = UpdateProject(ctx, settings.ProjectKey, settings.Context, &settings.EnvKey)
+		if updateErr != nil {
+			return updateErr
+		}
 	}
 	for flagKey, val := range settings.Overrides {
 		_, err := UpsertOverride(ctx, settings.ProjectKey, flagKey, val)

internal/dev_server/model/sync_test.go

@@ -170,4 +170,22 @@ func TestInitialSync(t *testing.T) {
 		assert.NoError(t, err)
 	})
 
+	t.Run("If SyncOnce is set and the project already exists, return early", func(t *testing.T) {
+		api.EXPECT().GetSdkKey(gomock.Any(), projKey, sourceEnvKey).Return(sdkKey, nil)
+		sdk.EXPECT().GetAllFlagsState(gomock.Any(), gomock.Any(), sdkKey).Return(allFlagsState, nil)
+		api.EXPECT().GetAllFlags(gomock.Any(), projKey).Return(allFlags, nil)
+		store.EXPECT().InsertProject(gomock.Any(), gomock.Any()).Return(model.ErrAlreadyExists)
+
+		input := model.InitialProjectSettings{
+			Enabled:    true,
+			ProjectKey: projKey,
+			EnvKey:     sourceEnvKey,
+			Context:    nil,
+			SyncOnce:   true,
+		}
+		err := model.CreateOrSyncProject(ctx, input)
+
+		assert.NoError(t, err)
+	})
+
 }