s3: sync bucket info from filer (#3759)

weed/s3api/s3_constants/acp_ownership.go

@@ -0,0 +1,18 @@
+package s3_constants
+
+var (
+	OwnershipBucketOwnerPreferred = "BucketOwnerPreferred"
+	OwnershipObjectWriter         = "ObjectWriter"
+	OwnershipBucketOwnerEnforced  = "BucketOwnerEnforced"
+
+	DefaultOwnershipForCreate = OwnershipObjectWriter
+	DefaultOwnershipForExists = OwnershipBucketOwnerEnforced
+)
+
+func ValidateOwnership(ownership string) bool {
+	if ownership == "" || (ownership != OwnershipBucketOwnerPreferred && ownership != OwnershipObjectWriter && ownership != OwnershipBucketOwnerEnforced) {
+		return false
+	} else {
+		return true
+	}
+}