Patch/delete double whitespace (#118)

* imple DeleteDoubleWhiteSpace

* fix blank check

pkg/execute/executor.go

@@ -3,7 +3,6 @@ package execute
 import (
 	"bytes"
 	"fmt"
-	"gopkg.in/yaml.v2"
 	"io/ioutil"
 	"os"
 	"os/exec"
@@ -13,9 +12,12 @@ import (
 	"text/tabwriter"
 	"unicode"
 
+	"gopkg.in/yaml.v2"
+
 	"github.com/infracloudio/botkube/pkg/config"
 	filterengine "github.com/infracloudio/botkube/pkg/filterengine"
 	log "github.com/infracloudio/botkube/pkg/logging"
+	"github.com/infracloudio/botkube/pkg/utils"
 )
 
 var validKubectlCommands = map[string]bool{
@@ -178,7 +180,7 @@ func trimQuotes(clusterValue string) string {
 
 func runKubectlCommand(args []string, clusterName string, isAuthChannel bool) string {
 	// Use 'default' as a default namespace
-	args = append([]string{"-n", "default"}, args...)
+	args = append([]string{"-n", "default"}, utils.DeleteDoubleWhiteSpace(args)...)
 
 	// Remove unnecessary flags
 	finalArgs := []string{}

pkg/utils/utils.go

@@ -225,3 +225,14 @@ func GetObjectTypeMetaData(obj interface{}) metaV1.TypeMeta {
 	}
 	return typeMeta
 }
+
+// DeleteDoubleWhiteSpace returns slice that removing whitespace from a arg slice
+func DeleteDoubleWhiteSpace(slice []string) []string {
+	result := []string{}
+	for _, s := range slice {
+		if len(s) != 0 {
+			result = append(result, s)
+		}
+	}
+	return result
+}