read and check ofx 2.x file header

pkg/converters/ofx/ofx_data_reader.go

@@ -1,17 +1,25 @@
 package ofx
 
 import (
+	"bufio"
 	"bytes"
 	"encoding/xml"
+	"regexp"
+	"strings"
 
 	"golang.org/x/net/html/charset"
 
 	"github.com/mayswind/ezbookkeeping/pkg/core"
 	"github.com/mayswind/ezbookkeeping/pkg/errs"
+	"github.com/mayswind/ezbookkeeping/pkg/log"
 )
 
+var ofx2HeaderPattern = regexp.MustCompile("<\\?OFX( +[A-Z]+=\"[^=]*\")* *\\?>")
+var ofx2HeaderAttributePattern = regexp.MustCompile(" +([A-Z]+)=\"([^=]*)\"")
+
 // ofxFileReader defines the structure of open financial exchange (ofx) file reader
 type ofxFileReader struct {
+	fileHeader *ofxFileHeader
 	xmlDecoder *xml.Decoder
 }
 
@@ -25,27 +33,97 @@ func (r *ofxFileReader) read(ctx core.Context) (*ofxFile, error) {
 		return nil, err
 	}
 
+	file.FileHeader = r.fileHeader
+
 	return file, nil
 }
 
-func createNewOFXFileReader(data []byte) (*ofxFileReader, error) {
-	if len(data) > 5 && data[0] == 0x3C && data[1] == 0x3F && data[2] == 0x78 && data[3] == 0x6D && data[4] == 0x6C { // ofx 2.x starts with <?xml
-		xmlDecoder := xml.NewDecoder(bytes.NewReader(data))
-		xmlDecoder.CharsetReader = charset.NewReaderLabel
-
-		return &ofxFileReader{
-			xmlDecoder: xmlDecoder,
-		}, nil
-	} else if len(data) > 13 && string(data[0:13]) == "OFXHEADER:100" { // ofx 1.x starts with OFXHEADER:100
+func createNewOFXFileReader(ctx core.Context, data []byte) (*ofxFileReader, error) {
+	if len(data) > 5 && string(data[0:5]) == "<?xml" { // ofx 2.x starts with <?xml
+		return createNewOFX2FileReader(ctx, data, true)
+	} else if len(data) > 10 && string(data[0:10]) == "OFXHEADER:" { // ofx 1.x starts with OFXHEADER:
 
 	} else if len(data) > 5 && string(data[0:5]) == "<OFX>" { // no ofx header
-		xmlDecoder := xml.NewDecoder(bytes.NewReader(data))
-		xmlDecoder.CharsetReader = charset.NewReaderLabel
-
-		return &ofxFileReader{
-			xmlDecoder: xmlDecoder,
-		}, nil
+		return createNewOFX2FileReader(ctx, data, false)
 	}
 
 	return nil, errs.ErrInvalidOFXFile
 }
+
+func createNewOFX2FileReader(ctx core.Context, data []byte, withHeader bool) (*ofxFileReader, error) {
+	var fileHeader *ofxFileHeader = nil
+	var err error
+
+	if withHeader {
+		fileHeader, err = readOFX2FileHeader(ctx, data)
+
+		if err != nil {
+			return nil, err
+		}
+
+		if fileHeader.OFXDeclarationVersion != ofxVersion2 {
+			log.Errorf(ctx, "[ofx_data_reader.createNewOFX2FileReader] cannot parse ofx 2.x file header, because declaration version is \"%s\"", fileHeader.OFXDeclarationVersion)
+			return nil, errs.ErrInvalidOFXFile
+		}
+	}
+
+	xmlDecoder := xml.NewDecoder(bytes.NewReader(data))
+	xmlDecoder.CharsetReader = charset.NewReaderLabel
+
+	return &ofxFileReader{
+		fileHeader: fileHeader,
+		xmlDecoder: xmlDecoder,
+	}, nil
+}
+
+func readOFX2FileHeader(ctx core.Context, data []byte) (fileHeader *ofxFileHeader, err error) {
+	reader := bytes.NewReader(data)
+	scanner := bufio.NewScanner(reader)
+	fileHeader = &ofxFileHeader{}
+	headerLine := ""
+
+	for scanner.Scan() {
+		line := scanner.Text()
+
+		ofxHeaderStartIndex := strings.Index(line, "<?OFX ")
+
+		if ofxHeaderStartIndex >= 0 {
+			headerLine = ofx2HeaderPattern.FindString(line)
+			break
+		}
+	}
+
+	if headerLine == "" {
+		log.Errorf(ctx, "[ofx_data_reader.readOFX2FileHeader] cannot find ofx 2.x file header")
+		return nil, errs.ErrInvalidOFXFile
+	}
+
+	headerAttributes := ofx2HeaderAttributePattern.FindAllStringSubmatch(headerLine, -1)
+
+	for _, attributeItems := range headerAttributes {
+		if len(attributeItems) != 3 {
+			log.Warnf(ctx, "[ofx_data_reader.readOFX2FileHeader] cannot parse line in ofx 2.x file header, because item is \"%s\"", attributeItems)
+			continue
+		}
+
+		name := attributeItems[1]
+		value := attributeItems[2]
+
+		if name == "OFXHEADER" {
+			fileHeader.OFXDeclarationVersion = oFXDeclarationVersion(value)
+		} else if name == "VERSION" {
+			fileHeader.OFXDataVersion = value
+		} else if name == "SECURITY" {
+			fileHeader.Security = value
+		} else if name == "OLDFILEUID" {
+			fileHeader.OldFileUid = value
+		} else if name == "NEWFILEUID" {
+			fileHeader.NewFileUid = value
+		} else {
+			log.Warnf(ctx, "[ofx_data_reader.readOFX2FileHeader] cannot parse unknown header line in ofx 2.x file header, because item is \"%s\"", attributeItems)
+			continue
+		}
+	}
+
+	return fileHeader, nil
+}