alps/imap.go
Simon Ser 61ffc105fd
Use imap.BodyStructure.Filename and imap.Address.Address
The former fixes encoding issues in filenames. The latter is just for
brevity.
2019-12-09 13:45:15 +01:00

306 lines
6.6 KiB
Go

package koushin
import (
"bufio"
"fmt"
"sort"
"strconv"
"strings"
"github.com/emersion/go-imap"
imapclient "github.com/emersion/go-imap/client"
"github.com/emersion/go-message"
"github.com/emersion/go-message/charset"
"github.com/emersion/go-message/textproto"
)
func init() {
imap.CharsetReader = charset.Reader
}
func (s *Server) connectIMAP() (*imapclient.Client, error) {
var c *imapclient.Client
var err error
if s.imap.tls {
c, err = imapclient.DialTLS(s.imap.host, nil)
if err != nil {
return nil, fmt.Errorf("failed to connect to IMAPS server: %v", err)
}
} else {
c, err = imapclient.Dial(s.imap.host)
if err != nil {
return nil, fmt.Errorf("failed to connect to IMAP server: %v", err)
}
if !s.imap.insecure {
if err := c.StartTLS(nil); err != nil {
c.Close()
return nil, fmt.Errorf("STARTTLS failed: %v", err)
}
}
}
return c, err
}
func listMailboxes(conn *imapclient.Client) ([]*imap.MailboxInfo, error) {
ch := make(chan *imap.MailboxInfo, 10)
done := make(chan error, 1)
go func() {
done <- conn.List("", "*", ch)
}()
var mailboxes []*imap.MailboxInfo
for mbox := range ch {
mailboxes = append(mailboxes, mbox)
}
if err := <-done; err != nil {
return nil, fmt.Errorf("failed to list mailboxes: %v", err)
}
sort.Slice(mailboxes, func(i, j int) bool {
return mailboxes[i].Name < mailboxes[j].Name
})
return mailboxes, nil
}
func ensureMailboxSelected(conn *imapclient.Client, mboxName string) error {
mbox := conn.Mailbox()
if mbox == nil || mbox.Name != mboxName {
if _, err := conn.Select(mboxName, false); err != nil {
return fmt.Errorf("failed to select mailbox: %v", err)
}
}
return nil
}
type imapMessage struct {
*imap.Message
}
func textPartPath(bs *imap.BodyStructure) ([]int, bool) {
if bs.Disposition != "" && !strings.EqualFold(bs.Disposition, "inline") {
return nil, false
}
if strings.EqualFold(bs.MIMEType, "text") {
return []int{1}, true
}
if !strings.EqualFold(bs.MIMEType, "multipart") {
return nil, false
}
textPartNum := -1
for i, part := range bs.Parts {
num := i + 1
if strings.EqualFold(part.MIMEType, "multipart") {
if subpath, ok := textPartPath(part); ok {
return append([]int{num}, subpath...), true
}
}
if !strings.EqualFold(part.MIMEType, "text") {
continue
}
var pick bool
switch strings.ToLower(part.MIMESubType) {
case "plain":
pick = true
case "html":
pick = textPartNum < 0
}
if pick {
textPartNum = num
}
}
if textPartNum > 0 {
return []int{textPartNum}, true
}
return nil, false
}
func (msg *imapMessage) TextPartName() string {
if msg.BodyStructure == nil {
return ""
}
path, ok := textPartPath(msg.BodyStructure)
if !ok {
return ""
}
l := make([]string, len(path))
for i, partNum := range path {
l[i] = strconv.Itoa(partNum)
}
return strings.Join(l, ".")
}
type IMAPPartNode struct {
Path []int
MIMEType string
Filename string
Children []IMAPPartNode
}
func (node IMAPPartNode) PathString() string {
l := make([]string, len(node.Path))
for i, partNum := range node.Path {
l[i] = strconv.Itoa(partNum)
}
return strings.Join(l, ".")
}
func (node IMAPPartNode) IsText() bool {
return strings.HasPrefix(strings.ToLower(node.MIMEType), "text/")
}
func (node IMAPPartNode) String() string {
if node.Filename != "" {
return fmt.Sprintf("%s (%s)", node.Filename, node.MIMEType)
} else {
return node.MIMEType
}
}
func imapPartTree(bs *imap.BodyStructure, path []int) *IMAPPartNode {
if !strings.EqualFold(bs.MIMEType, "multipart") && len(path) == 0 {
path = []int{1}
}
filename, _ := bs.Filename()
node := &IMAPPartNode{
Path: path,
MIMEType: strings.ToLower(bs.MIMEType + "/" + bs.MIMESubType),
Filename: filename,
Children: make([]IMAPPartNode, len(bs.Parts)),
}
for i, part := range bs.Parts {
num := i + 1
partPath := append([]int(nil), path...)
partPath = append(partPath, num)
node.Children[i] = *imapPartTree(part, partPath)
}
return node
}
func (msg *imapMessage) PartTree() *IMAPPartNode {
if msg.BodyStructure == nil {
return nil
}
return imapPartTree(msg.BodyStructure, nil)
}
func listMessages(conn *imapclient.Client, mboxName string, page int) ([]imapMessage, error) {
if err := ensureMailboxSelected(conn, mboxName); err != nil {
return nil, err
}
mbox := conn.Mailbox()
to := int(mbox.Messages) - page*messagesPerPage
from := to - messagesPerPage + 1
if from <= 0 {
from = 1
}
if to <= 0 {
return nil, nil
}
seqSet := new(imap.SeqSet)
seqSet.AddRange(uint32(from), uint32(to))
fetch := []imap.FetchItem{imap.FetchEnvelope, imap.FetchUid, imap.FetchBodyStructure}
ch := make(chan *imap.Message, 10)
done := make(chan error, 1)
go func() {
done <- conn.Fetch(seqSet, fetch, ch)
}()
msgs := make([]imapMessage, 0, to-from)
for msg := range ch {
msgs = append(msgs, imapMessage{msg})
}
if err := <-done; err != nil {
return nil, fmt.Errorf("failed to fetch message list: %v", err)
}
// Reverse list of messages
for i := len(msgs)/2 - 1; i >= 0; i-- {
opp := len(msgs) - 1 - i
msgs[i], msgs[opp] = msgs[opp], msgs[i]
}
return msgs, nil
}
func getMessagePart(conn *imapclient.Client, mboxName string, uid uint32, partPath []int) (*imapMessage, *message.Entity, error) {
if err := ensureMailboxSelected(conn, mboxName); err != nil {
return nil, nil, err
}
seqSet := new(imap.SeqSet)
seqSet.AddNum(uid)
var partHeaderSection imap.BodySectionName
partHeaderSection.Peek = true
if len(partPath) > 0 {
partHeaderSection.Specifier = imap.MIMESpecifier
} else {
partHeaderSection.Specifier = imap.HeaderSpecifier
}
partHeaderSection.Path = partPath
var partBodySection imap.BodySectionName
partBodySection.Peek = true
if len(partPath) > 0 {
partBodySection.Specifier = imap.EntireSpecifier
} else {
partBodySection.Specifier = imap.TextSpecifier
}
partBodySection.Path = partPath
fetch := []imap.FetchItem{
imap.FetchEnvelope,
imap.FetchUid,
imap.FetchBodyStructure,
partHeaderSection.FetchItem(),
partBodySection.FetchItem(),
}
ch := make(chan *imap.Message, 1)
if err := conn.UidFetch(seqSet, fetch, ch); err != nil {
return nil, nil, fmt.Errorf("failed to fetch message: %v", err)
}
msg := <-ch
if msg == nil {
return nil, nil, fmt.Errorf("server didn't return message")
}
headerReader := bufio.NewReader(msg.GetBody(&partHeaderSection))
h, err := textproto.ReadHeader(headerReader)
if err != nil {
return nil, nil, fmt.Errorf("failed to read part header: %v", err)
}
part, err := message.New(message.Header{h}, msg.GetBody(&partBodySection))
if err != nil {
return nil, nil, fmt.Errorf("failed to create message reader: %v", err)
}
return &imapMessage{msg}, part, nil
}