feat(cli): send general error notifications only if the standard output is not a terminal (#4245)

cli/app.go

@@ -145,7 +145,7 @@ type App struct {
 	upgradeOwnerID      string
 	doNotWaitForUpgrade bool
 
-	errorNotifications bool
+	errorNotifications string
 
 	currentAction         string
 	onExitCallbacks       []func()
@@ -248,10 +248,6 @@ func (c *App) passwordPersistenceStrategy() passwordpersist.Strategy {
 	return passwordpersist.File()
 }
 
-func (c *App) enableErrorNotifications() bool {
-	return c.errorNotifications
-}
-
 func (c *App) setup(app *kingpin.Application) {
 	app.PreAction(func(pc *kingpin.ParseContext) error {
 		if sc := pc.SelectedCommand; sc != nil {
@@ -286,7 +282,10 @@ func (c *App) setup(app *kingpin.Application) {
 	app.Flag("dump-allocator-stats", "Dump allocator stats at the end of execution.").Hidden().Envar(c.EnvName("KOPIA_DUMP_ALLOCATOR_STATS")).BoolVar(&c.dumpAllocatorStats)
 	app.Flag("upgrade-owner-id", "Repository format upgrade owner-id.").Hidden().Envar(c.EnvName("KOPIA_REPO_UPGRADE_OWNER_ID")).StringVar(&c.upgradeOwnerID)
 	app.Flag("upgrade-no-block", "Do not block when repository format upgrade is in progress, instead exit with a message.").Hidden().Default("false").Envar(c.EnvName("KOPIA_REPO_UPGRADE_NO_BLOCK")).BoolVar(&c.doNotWaitForUpgrade)
-	app.Flag("error-notifications", "Send notification on errors").Hidden().Envar(c.EnvName("KOPIA_SEND_ERROR_NOTIFICATIONS")).Default("true").BoolVar(&c.errorNotifications)
+	app.Flag("error-notifications", "Send notification on errors").Hidden().
+		Envar(c.EnvName("KOPIA_SEND_ERROR_NOTIFICATIONS")).
+		Default(errorNotificationsNonInteractive).
+		EnumVar(&c.errorNotifications, errorNotificationsAlways, errorNotificationsNever, errorNotificationsNonInteractive)
 
 	if c.enableTestOnlyFlags() {
 		app.Flag("ignore-missing-required-features", "Open repository despite missing features (VERY DANGEROUS, ONLY FOR TESTING)").Hidden().BoolVar(&c.testonlyIgnoreMissingRequiredFeatures)
@@ -585,7 +584,7 @@ func (c *App) maybeRepositoryAction(act func(ctx context.Context, rep repo.Repos
 			}
 		}
 
-		if err != nil && rep != nil && c.errorNotifications {
+		if err != nil && c.enableErrorNotifications() && rep != nil {
 			notification.Send(ctx, rep, "generic-error", notifydata.NewErrorInfo(
 				c.currentActionName(),
 				c.currentActionName(),

cli/error_notifications.go

@@ -0,0 +1,38 @@
+package cli
+
+import (
+	"os"
+
+	"github.com/mattn/go-isatty"
+)
+
+const (
+	errorNotificationsNever          = "never"
+	errorNotificationsAlways         = "always"
+	errorNotificationsNonInteractive = "non-interactive"
+)
+
+func (c *App) enableErrorNotifications() bool {
+	switch c.errorNotifications {
+	case errorNotificationsNever:
+		return false
+
+	case errorNotificationsAlways:
+		return true
+
+	case errorNotificationsNonInteractive:
+		if c.isInProcessTest {
+			return false
+		}
+
+		if isatty.IsTerminal(os.Stdout.Fd()) || isatty.IsCygwinTerminal(os.Stdout.Fd()) {
+			// interactive terminal, don't send notifications
+			return false
+		}
+
+		return true
+
+	default:
+		return false
+	}
+}

go.mod

@@ -31,6 +31,7 @@ require (
 	github.com/kopia/htmluibuild v0.0.1-0.20241105060252-108f70b353de
 	github.com/kylelemons/godebug v1.1.0
 	github.com/mattn/go-colorable v0.1.13
+	github.com/mattn/go-isatty v0.0.20
 	github.com/minio/minio-go/v7 v7.0.80
 	github.com/mocktools/go-smtp-mock/v2 v2.3.1
 	github.com/mxk/go-vss v1.2.0
@@ -122,7 +123,6 @@ require (
 	github.com/klauspost/cpuid/v2 v2.2.8 // indirect
 	github.com/kr/fs v0.1.0 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
-	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/minio/md5-simd v1.1.2 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
 	github.com/pkg/browser v0.0.0-20240102092130-5ac0b6a4141c // indirect