getimap/vendor/github.com/emersion/go-message/mail/writer.go
2020-03-10 13:57:28 +01:00

113 lines
3.2 KiB
Go

package mail
import (
"io"
"strings"
"github.com/emersion/go-message"
)
func initInlineContentTransferEncoding(h *message.Header) {
if !h.Has("Content-Transfer-Encoding") {
t, _, _ := h.ContentType()
if strings.HasPrefix(t, "text/") {
h.Set("Content-Transfer-Encoding", "quoted-printable")
} else {
h.Set("Content-Transfer-Encoding", "base64")
}
}
}
func initInlineHeader(h *InlineHeader) {
h.Set("Content-Disposition", "inline")
initInlineContentTransferEncoding(&h.Header)
}
func initAttachmentHeader(h *AttachmentHeader) {
disp, _, _ := h.ContentDisposition()
if disp != "attachment" {
h.Set("Content-Disposition", "attachment")
}
if !h.Has("Content-Transfer-Encoding") {
h.Set("Content-Transfer-Encoding", "base64")
}
}
// A Writer writes a mail message. A mail message contains one or more text
// parts and zero or more attachments.
type Writer struct {
mw *message.Writer
}
// CreateWriter writes a mail header to w and creates a new Writer.
func CreateWriter(w io.Writer, header Header) (*Writer, error) {
header.Set("Content-Type", "multipart/mixed")
mw, err := message.CreateWriter(w, header.Header)
if err != nil {
return nil, err
}
return &Writer{mw}, nil
}
// CreateSingleInlineWriter writes a mail header to w. The mail will contain a
// single inline part. The body of the part should be written to the returned
// io.WriteCloser. Only one single inline part should be written, use
// CreateWriter if you want multiple parts.
func CreateSingleInlineWriter(w io.Writer, header Header) (io.WriteCloser, error) {
initInlineContentTransferEncoding(&header.Header)
return message.CreateWriter(w, header.Header)
}
// CreateInline creates a InlineWriter. One or more parts representing the same
// text in different formats can be written to a InlineWriter.
func (w *Writer) CreateInline() (*InlineWriter, error) {
var h message.Header
h.Set("Content-Type", "multipart/alternative")
mw, err := w.mw.CreatePart(h)
if err != nil {
return nil, err
}
return &InlineWriter{mw}, nil
}
// CreateSingleInline creates a new single text part with the provided header.
// The body of the part should be written to the returned io.WriteCloser. Only
// one single text part should be written, use CreateInline if you want multiple
// text parts.
func (w *Writer) CreateSingleInline(h InlineHeader) (io.WriteCloser, error) {
initInlineHeader(&h)
return w.mw.CreatePart(h.Header)
}
// CreateAttachment creates a new attachment with the provided header. The body
// of the part should be written to the returned io.WriteCloser.
func (w *Writer) CreateAttachment(h AttachmentHeader) (io.WriteCloser, error) {
initAttachmentHeader(&h)
return w.mw.CreatePart(h.Header)
}
// Close finishes the Writer.
func (w *Writer) Close() error {
return w.mw.Close()
}
// InlineWriter writes a mail message's text.
type InlineWriter struct {
mw *message.Writer
}
// CreatePart creates a new text part with the provided header. The body of the
// part should be written to the returned io.WriteCloser.
func (w *InlineWriter) CreatePart(h InlineHeader) (io.WriteCloser, error) {
initInlineHeader(&h)
return w.mw.CreatePart(h.Header)
}
// Close finishes the InlineWriter.
func (w *InlineWriter) Close() error {
return w.mw.Close()
}