test: more chunked upload tests with different payload types

tests/rest_scripts/command/stringDataSource.go

@@ -0,0 +1,42 @@
+package command
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"io"
+	"strings"
+)
+
+type StringDataSource struct {
+	dataString string
+}
+
+func NewStringDataSource(dataString string) *StringDataSource {
+	return &StringDataSource{
+		dataString: dataString,
+	}
+}
+
+func (s *StringDataSource) SourceDataByteSize() (int64, error) {
+	return int64(len(s.dataString)), nil
+}
+
+func (s *StringDataSource) CalculateSHA256HashString() (string, error) {
+	hash := sha256.Sum256([]byte(s.dataString))
+	return hex.EncodeToString(hash[:]), nil
+}
+
+func (s *StringDataSource) Close() error {
+	return nil
+}
+
+func (s *StringDataSource) GetReader() (io.Reader, error) {
+	stringReader := strings.NewReader(s.dataString)
+	return stringReader, nil
+}
+
+func (s *StringDataSource) GetTeeReader(checksumWriter io.Writer) (io.Reader, error) {
+	stringReader := strings.NewReader(s.dataString)
+	r := io.TeeReader(stringReader, checksumWriter)
+	return r, nil
+}