From c63cdca11f5ecb85568c111efebc1dedf12e2857 Mon Sep 17 00:00:00 2001
From: Remco Verhoef <remco@dutchcoders.io>
Date: Wed, 10 May 2017 19:23:44 -0700
Subject: [PATCH] Support iterating through ListObjectParts using
 NextPartNumberMarker, closes #4284

---
 cmd/gateway-gcs.go | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/cmd/gateway-gcs.go b/cmd/gateway-gcs.go
index 9fe3035eb..3121422f5 100644
--- a/cmd/gateway-gcs.go
+++ b/cmd/gateway-gcs.go
@@ -697,20 +697,22 @@ func (l *gcsGateway) PutObjectPart(bucket string, key string, uploadID string, p
 
 // ListObjectParts returns all object parts for specified object in specified bucket
 func (l *gcsGateway) ListObjectParts(bucket string, key string, uploadID string, partNumberMarker int, maxParts int) (ListPartsInfo, error) {
-	// TODO: support partNumberMarker
-
-	prefix := fmt.Sprintf("%s/multipart-%s-%s", ZZZZMinioPrefix, key, uploadID)
+	prefix := ""
 	delimiter := "/"
 
 	it := l.client.Bucket(bucket).Objects(l.ctx, &storage.Query{Delimiter: delimiter, Prefix: prefix, Versions: false})
 
 	isTruncated := false
 
+	it.PageInfo().Token = toGCSMultipartKey(key, uploadID, partNumberMarker)
+	it.PageInfo().MaxSize = maxParts
+
+	nextPartnumberMarker := 0
+
 	parts := []PartInfo{}
 	for {
-		if maxParts <= len(parts) {
+		if len(parts) >= maxParts {
 			isTruncated = true
-			// nextMarker = it.PageInfo().Token
 			break
 		}
 
@@ -736,6 +738,8 @@ func (l *gcsGateway) ListObjectParts(bucket string, key string, uploadID string,
 			continue
 		}
 
+		nextPartnumberMarker = partID
+
 		parts = append(parts, PartInfo{
 			PartNumber:   partID,
 			LastModified: attrs.Updated,
@@ -745,8 +749,9 @@ func (l *gcsGateway) ListObjectParts(bucket string, key string, uploadID string,
 	}
 
 	return ListPartsInfo{
-		IsTruncated: isTruncated,
-		Parts:       parts,
+		IsTruncated:          isTruncated,
+		NextPartNumberMarker: nextPartnumberMarker,
+		Parts:                parts,
 	}, nil
 }