add unit test

pkg/api/common/helper_test.go

@@ -0,0 +1,49 @@
+package common
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestValidateDNSPrefix(t *testing.T) {
+	cases := []struct {
+		dnsPrefix   string
+		expectedErr error
+	}{
+		{
+			"validDnsPrefix",
+			nil,
+		},
+		{
+			"",
+			fmt.Errorf("DNSPrefix '' is invalid. The DNSPrefix must contain between 3 and 45 characters. The name can contain only letters, numbers, and hyphens.  The name must start with a letter and must end with a letter or a number. (length was 0)"),
+		},
+		{
+			"1232",
+			fmt.Errorf("DNSPrefix '1234' is invalid. The DNSPrefix must contain between 3 and 45 characters. The name can contain only letters, numbers, and hyphens.  The name must start with a letter and must end with a letter or a number. (length was 4)"),
+		},
+		{
+			"verylongdnsprefixthatismorethan45characterslong",
+			fmt.Errorf("DNSPrefix 'verylongdnsprefixthatismorethan45characterslong' is invalid. The DNSPrefix must contain between 3 and 45 characters. The name can contain only letters, numbers, and hyphens.  The name must start with a letter and must end with a letter or a number. (length was 47)"),
+		},
+		{
+			"dnswith_special?char",
+			fmt.Errorf("DNSPrefix 'dnswith_special?char' is invalid. The DNSPrefix must contain between 3 and 45 characters. The name can contain only letters, numbers, and hyphens.  The name must start with a letter and must end with a letter or a number. (length was 15)"),
+		},
+		{
+			"myDNS-1234",
+			nil,
+		},
+	}
+
+	for _, c := range cases {
+		err := ValidateDNSPrefix(c.dnsPrefix)
+		if err != c.expectedErr {
+			if c.expectedErr != nil {
+				t.Fatalf("expected validateDNSPrefix to return error %s, but instead got %s", c.expectedErr.Error(), err.Error())
+			} else {
+				t.Fatalf("expected validateDNSPrefix to return no error, but instead got %s", err.Error())
+			}
+		}
+	}
+}

pkg/api/vlabs/validate_test.go

@@ -971,7 +971,7 @@ func TestMasterProfileValidate(t *testing.T) {
 			masterProfile: MasterProfile{
 				DNSPrefix: "bad!",
 			},
-			expectedErr: "DNS prefix 'bad!' is invalid. The DNS prefix must contain between 3 and 45 characters.  The name can contain only letters, numbers, and hyphens.  The name must start with a letter and must end with a letter or a number (length was 4)",
+			expectedErr: "DNSPrefix 'bad!' is invalid. The DNSPrefix must contain between 3 and 45 characters.  The name can contain only letters, numbers, and hyphens.  The name must start with a letter and must end with a letter or a number (length was 4)",
 		},
 		{
 			masterProfile: MasterProfile{