Swift driver now bulk deletes in chunks specified by the server (#1915)

Swift driver now bulk deletes in chunks specified by the server

Signed-off-by: Matthew Green <matthew.green@uk.ibm.com>

registry/storage/driver/swift/swift_test.go

@@ -3,6 +3,7 @@ package swift
 import (
 	"io/ioutil"
 	"os"
+	"reflect"
 	"strconv"
 	"strings"
 	"testing"
@@ -181,3 +182,64 @@ func TestEmptyRootList(t *testing.T) {
 		t.Fatal("delete did not remove nested objects")
 	}
 }
+
+func TestFilenameChunking(t *testing.T) {
+	// Test valid input and sizes
+	input := []string{"a", "b", "c", "d", "e"}
+	expecteds := [][][]string{
+		{
+			{"a"},
+			{"b"},
+			{"c"},
+			{"d"},
+			{"e"},
+		},
+		{
+			{"a", "b"},
+			{"c", "d"},
+			{"e"},
+		},
+		{
+			{"a", "b", "c"},
+			{"d", "e"},
+		},
+		{
+			{"a", "b", "c", "d"},
+			{"e"},
+		},
+		{
+			{"a", "b", "c", "d", "e"},
+		},
+		{
+			{"a", "b", "c", "d", "e"},
+		},
+	}
+	for i, expected := range expecteds {
+		actual, err := chunkFilenames(input, i+1)
+		if !reflect.DeepEqual(actual, expected) {
+			t.Fatalf("chunk %v didn't match expected value %v", actual, expected)
+		}
+		if err != nil {
+			t.Fatalf("unexpected error chunking filenames: %v", err)
+		}
+	}
+
+	// Test nil input
+	actual, err := chunkFilenames(nil, 5)
+	if len(actual) != 0 {
+		t.Fatal("chunks were returned when passed nil")
+	}
+	if err != nil {
+		t.Fatalf("unexpected error chunking filenames: %v", err)
+	}
+
+	// Test 0 and < 0 sizes
+	actual, err = chunkFilenames(nil, 0)
+	if err == nil {
+		t.Fatal("expected error for size = 0")
+	}
+	actual, err = chunkFilenames(nil, -1)
+	if err == nil {
+		t.Fatal("expected error for size = -1")
+	}
+}