Fix S3 Select request XML parsing (#7202)

pkg/s3select/csv/args.go

@@ -65,6 +65,8 @@ func (args *ReaderArgs) UnmarshalXML(d *xml.Decoder, start xml.StartElement) err
 
 	parsedArgs.FileHeaderInfo = strings.ToLower(parsedArgs.FileHeaderInfo)
 	switch parsedArgs.FileHeaderInfo {
+	case "":
+		parsedArgs.FileHeaderInfo = none
 	case none, use, ignore:
 	default:
 		return errInvalidFileHeaderInfo(fmt.Errorf("invalid FileHeaderInfo '%v'", parsedArgs.FileHeaderInfo))

pkg/s3select/select.go

@@ -99,6 +99,11 @@ func (input *InputSerialization) UnmarshalXML(d *xml.Decoder, start xml.StartEle
 		return errMalformedXML(err)
 	}
 
+	// If no compression is specified, set to noneType
+	if parsedInput.CompressionType == CompressionType("") {
+		parsedInput.CompressionType = noneType
+	}
+
 	found := 0
 	if !parsedInput.CSVArgs.IsEmpty() {
 		parsedInput.format = csvFormat
@@ -172,10 +177,10 @@ type RequestProgress struct {
 }
 
 // S3Select - filters the contents on a simple structured query language (SQL) statement. It
-// represents elements inside <SelectObjectContentRequest/> in request XML specified in detail at
+// represents elements inside <SelectRequest/> in request XML specified in detail at
 // https://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectSELECTContent.html.
 type S3Select struct {
-	XMLName        xml.Name            `xml:"SelectObjectContentRequest"`
+	XMLName        xml.Name            `xml:"SelectRequest"`
 	Expression     string              `xml:"Expression"`
 	ExpressionType string              `xml:"ExpressionType"`
 	Input          InputSerialization  `xml:"InputSerialization"`
@@ -187,8 +192,20 @@ type S3Select struct {
 	recordReader   recordReader
 }
 
+var (
+	legacyXMLName = "SelectObjectContentRequest"
+)
+
 // UnmarshalXML - decodes XML data.
 func (s3Select *S3Select) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
+	// S3 also supports the older SelectObjectContentRequest tag,
+	// though it is no longer found in documentation. This is
+	// checked and renamed below to allow older clients to also
+	// work.
+	if start.Name.Local == legacyXMLName {
+		start.Name = xml.Name{Space: "", Local: "SelectRequest"}
+	}
+
 	// Make subtype to avoid recursive UnmarshalXML().
 	type subS3Select S3Select
 	parsedS3Select := subS3Select{}