Restore the Part's buffer after reading its content

envelope.go

@@ -1,6 +1,7 @@
 package enmime
 
 import (
+	"bytes"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -147,6 +148,7 @@ func parseTextOnlyBody(root *Part, e *Envelope) error {
 
 	// Read transcoded text
 	bodyBytes, err := ioutil.ReadAll(root)
+	root.Utf8Reader = bytes.NewReader(bodyBytes)
 	if err != nil {
 		return err
 	}
@@ -225,6 +227,7 @@ func parseMultiPartBody(root *Part, e *Envelope) error {
 			if ioerr != nil {
 				return ioerr
 			}
+			p.Utf8Reader = bytes.NewReader(allBytes)
 			e.Text = string(allBytes)
 		}
 	} else {
@@ -240,6 +243,7 @@ func parseMultiPartBody(root *Part, e *Envelope) error {
 			if ioerr != nil {
 				return ioerr
 			}
+			p.Utf8Reader = bytes.NewReader(allBytes)
 			e.Text += string(allBytes)
 		}
 	}
@@ -251,6 +255,7 @@ func parseMultiPartBody(root *Part, e *Envelope) error {
 		if ioerr != nil {
 			return ioerr
 		}
+		p.Utf8Reader = bytes.NewReader(allBytes)
 		e.HTML += string(allBytes)
 	}
 

part.go

@@ -24,11 +24,11 @@ type Part struct {
 	FileName    string               // The file-name from disposition or type header
 	Charset     string               // The content charset encoding label
 	Errors      []Error              // Errors encountered while parsing this part
+	Utf8Reader  io.Reader            // The decoded content converted to UTF-8
 
 	boundary      string    // Boundary marker used within this part
 	rawReader     io.Reader // The raw Part content, no decoding or charset conversion
 	decodedReader io.Reader // The content decoded from quoted-printable or base64
-	utf8Reader    io.Reader // The decoded content converted to UTF-8
 }
 
 // NewPart creates a new Part object.  It does not update the parents FirstChild attribute.
@@ -38,10 +38,10 @@ func NewPart(parent *Part, contentType string) *Part {
 
 // Read returns the decoded & UTF-8 converted content; implements io.Reader.
 func (p *Part) Read(b []byte) (n int, err error) {
-	if p.utf8Reader == nil {
+	if p.Utf8Reader == nil {
 		return 0, io.EOF
 	}
-	return p.utf8Reader.Read(b)
+	return p.Utf8Reader.Read(b)
 }
 
 // setupContentHeaders uses Content-Type media params and Content-Disposition headers to populate
@@ -127,7 +127,7 @@ func (p *Part) buildContentReaders(r io.Reader) error {
 			}
 		}
 	}
-	p.utf8Reader = contentReader
+	p.Utf8Reader = contentReader
 	return nil
 }