Handle missing credentials gracefully

Signed-off-by: Knut Ahlers <knut@ahlers.me>

main.go

@@ -86,8 +86,18 @@ func handleGetAction() {
 	}
 
 	vaultValues, err := getCredentialSetFromVault(values["host"])
-	if err != nil {
+	switch err {
+
+	case nil:
+		// Fine
+
+	case errNoData:
+		// Return empty, git will handle the rest
+		return
+
+	default:
 		log.WithError(err).Fatal("Unable to retrieve values from Vault")
+
 	}
 
 	for k, v := range vaultValues {

vault.go

@@ -7,6 +7,8 @@ import (
 	"github.com/pkg/errors"
 )
 
+var errNoData = errors.New("Found no data")
+
 func getCredentialSetFromVault(host string) (map[string]string, error) {
 	client, err := api.NewClient(nil)
 	if err != nil {
@@ -19,7 +21,7 @@ func getCredentialSetFromVault(host string) (map[string]string, error) {
 	}
 
 	if secret == nil || secret.Data == nil {
-		return nil, errors.New("Found no data")
+		return nil, errNoData
 	}
 
 	var out = map[string]string{}