Initialize module and dependencies

vendor/github.com/emersion/go-message/header.go

@@ -0,0 +1,118 @@
+package message
+
+import (
+	"mime"
+
+	"github.com/emersion/go-message/textproto"
+)
+
+func parseHeaderWithParams(s string) (f string, params map[string]string, err error) {
+	f, params, err = mime.ParseMediaType(s)
+	if err != nil {
+		return s, nil, err
+	}
+	for k, v := range params {
+		params[k], _ = decodeHeader(v)
+	}
+	return
+}
+
+func formatHeaderWithParams(f string, params map[string]string) string {
+	encParams := make(map[string]string)
+	for k, v := range params {
+		encParams[k] = encodeHeader(v)
+	}
+	return mime.FormatMediaType(f, encParams)
+}
+
+// HeaderFields iterates over header fields.
+type HeaderFields interface {
+	textproto.HeaderFields
+
+	// Text parses the value of the current field as plaintext. The field
+	// charset is decoded to UTF-8. If the header field's charset is unknown,
+	// the raw field value is returned and the error verifies IsUnknownCharset.
+	Text() (string, error)
+}
+
+type headerFields struct {
+	textproto.HeaderFields
+}
+
+func (hf *headerFields) Text() (string, error) {
+	return decodeHeader(hf.Value())
+}
+
+// A Header represents the key-value pairs in a message header.
+type Header struct {
+	textproto.Header
+}
+
+// HeaderFromMap creates a header from a map of header fields.
+//
+// This function is provided for interoperability with the standard library.
+// If possible, ReadHeader should be used instead to avoid loosing information.
+// The map representation looses the ordering of the fields, the capitalization
+// of the header keys, and the whitespace of the original header.
+func HeaderFromMap(m map[string][]string) Header {
+	return Header{textproto.HeaderFromMap(m)}
+}
+
+// ContentType parses the Content-Type header field.
+//
+// If no Content-Type is specified, it returns "text/plain".
+func (h *Header) ContentType() (t string, params map[string]string, err error) {
+	v := h.Get("Content-Type")
+	if v == "" {
+		return "text/plain", nil, nil
+	}
+	return parseHeaderWithParams(v)
+}
+
+// SetContentType formats the Content-Type header field.
+func (h *Header) SetContentType(t string, params map[string]string) {
+	h.Set("Content-Type", formatHeaderWithParams(t, params))
+}
+
+// ContentDisposition parses the Content-Disposition header field, as defined in
+// RFC 2183.
+func (h *Header) ContentDisposition() (disp string, params map[string]string, err error) {
+	return parseHeaderWithParams(h.Get("Content-Disposition"))
+}
+
+// SetContentDisposition formats the Content-Disposition header field, as
+// defined in RFC 2183.
+func (h *Header) SetContentDisposition(disp string, params map[string]string) {
+	h.Set("Content-Disposition", formatHeaderWithParams(disp, params))
+}
+
+// Text parses a plaintext header field. The field charset is automatically
+// decoded to UTF-8. If the header field's charset is unknown, the raw field
+// value is returned and the error verifies IsUnknownCharset.
+func (h *Header) Text(k string) (string, error) {
+	return decodeHeader(h.Get(k))
+}
+
+// SetText sets a plaintext header field.
+func (h *Header) SetText(k, v string) {
+	h.Set(k, encodeHeader(v))
+}
+
+// Copy creates a stand-alone copy of the header.
+func (h *Header) Copy() Header {
+	return Header{h.Header.Copy()}
+}
+
+// Fields iterates over all the header fields.
+//
+// The header may not be mutated while iterating, except using HeaderFields.Del.
+func (h *Header) Fields() HeaderFields {
+	return &headerFields{h.Header.Fields()}
+}
+
+// FieldsByKey iterates over all fields having the specified key.
+//
+// The header may not be mutated while iterating, except using HeaderFields.Del.
+func (h *Header) FieldsByKey(k string) HeaderFields {
+	return &headerFields{h.Header.FieldsByKey(k)}
+}