Exit status 3 when backend already initialized (#3464)

* Exit status 3 when backend already initialized

Signed-off-by: Eric Chlebek <eric@sensu.io>

* Fix tests

Signed-off-by: Eric Chlebek <eric@sensu.io>

backend/cmd/init.go

@@ -170,7 +170,7 @@ func seedCluster(client *clientv3.Client, config seedConfig) error {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Second*5)
 	defer cancel()
 	if err := seeds.SeedCluster(ctx, store, config.SeedConfig); err != nil {
-		return fmt.Errorf("error initializing cluster: %s", err)
+		return err
 	}
 	return nil
 }

backend/seeds/seeds.go

@@ -2,6 +2,7 @@ package seeds
 
 import (
 	"context"
+	"errors"
 	"time"
 
 	corev2 "github.com/sensu/sensu-go/api/core/v2"
@@ -18,6 +19,8 @@ type Config struct {
 	AdminPassword string
 }
 
+var ErrAlreadyInitialized = errors.New("sensu-backend already initialized")
+
 // SeedCluster seeds the cluster according to the provided config.
 func SeedCluster(ctx context.Context, store store.Store, config Config) error {
 	errs := make(chan error, 1)
@@ -47,10 +50,17 @@ func SeedCluster(ctx context.Context, store store.Store, config Config) error {
 		}()
 
 		// Check that the store hasn't already been seeded
-		initialized, err := initializer.IsInitialized()
-		if err != nil || initialized {
+		var initialized bool
+		initialized, err = initializer.IsInitialized()
+		if err != nil {
 			return
 		}
+		if initialized {
+			logger.Info("store already initialized")
+			err = ErrAlreadyInitialized
+			return
+		}
+
 		logger.Info("seeding etcd store with intial data")
 
 		// Create the default namespace

backend/seeds/seeds_test.go

@@ -22,7 +22,9 @@ func TestSeedInitialData(t *testing.T) {
 	require.NoError(t, err, "seeding process should not raise an error")
 
 	err = SeedInitialData(st)
-	require.NoError(t, err, "seeding process should be able to be run more than once without error")
+	if err != ErrAlreadyInitialized {
+		require.NoError(t, err, "seeding process should be able to be run more than once without error")
+	}
 
 	admin, err := st.GetUser(ctx, "admin")
 	require.NoError(t, err)

cmd/sensu-backend/main.go

@@ -2,9 +2,11 @@ package main
 
 import (
 	_ "net/http/pprof"
+	"os"
 
 	"github.com/sensu/sensu-go/backend"
 	"github.com/sensu/sensu-go/backend/cmd"
+	"github.com/sensu/sensu-go/backend/seeds"
 	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 )
@@ -24,6 +26,9 @@ func main() {
 	rootCmd.AddCommand(cmd.InitCommand())
 
 	if err := rootCmd.Execute(); err != nil {
+		if err == seeds.ErrAlreadyInitialized {
+			os.Exit(3)
+		}
 		logger.WithError(err).Fatal("error executing sensu-backend")
 	}
 }