alps/plugins/base/imap.go

581 lines
13 KiB
Go
Executable file

package alpsbase
import (
"bufio"
"bytes"
"fmt"
"net/url"
"sort"
"strconv"
"strings"
"time"
"github.com/emersion/go-imap"
imapspecialuse "github.com/emersion/go-imap-specialuse"
imapclient "github.com/emersion/go-imap/client"
"github.com/emersion/go-message"
"github.com/emersion/go-message/textproto"
)
type MailboxInfo struct {
*imap.MailboxInfo
}
func (mbox *MailboxInfo) URL() *url.URL {
return &url.URL{
Path: fmt.Sprintf("/mailbox/%v", url.PathEscape(mbox.Name)),
}
}
func listMailboxes(conn *imapclient.Client) ([]MailboxInfo, error) {
ch := make(chan *imap.MailboxInfo, 10)
done := make(chan error, 1)
go func() {
done <- conn.List("", "*", ch)
}()
var mailboxes []MailboxInfo
for mbox := range ch {
mailboxes = append(mailboxes, MailboxInfo{mbox})
}
if err := <-done; err != nil {
return nil, fmt.Errorf("failed to list mailboxes: %v", err)
}
sort.Slice(mailboxes, func(i, j int) bool {
if mailboxes[i].Name == "INBOX" {
return true
}
if mailboxes[j].Name == "INBOX" {
return false
}
return mailboxes[i].Name < mailboxes[j].Name
})
return mailboxes, nil
}
type MailboxStatus struct {
*imap.MailboxStatus
}
func (mbox *MailboxStatus) URL() *url.URL {
return &url.URL{
Path: fmt.Sprintf("/mailbox/%v", url.PathEscape(mbox.Name)),
}
}
func getMailboxStatus(conn *imapclient.Client, name string) (*MailboxStatus, error) {
items := []imap.StatusItem{
imap.StatusMessages,
imap.StatusUidValidity,
imap.StatusUnseen,
}
status, err := conn.Status(name, items)
if err != nil {
return nil, fmt.Errorf("failed to get mailbox status: %v", err)
}
return &MailboxStatus{status}, nil
}
type mailboxType int
const (
mailboxSent mailboxType = iota
mailboxDrafts
)
func getMailboxByType(conn *imapclient.Client, mboxType mailboxType) (*MailboxInfo, error) {
ch := make(chan *imap.MailboxInfo, 10)
done := make(chan error, 1)
go func() {
done <- conn.List("", "%", ch)
}()
// TODO: configurable fallback names?
var attr string
var fallbackNames []string
switch mboxType {
case mailboxSent:
attr = imapspecialuse.Sent
fallbackNames = []string{"Sent"}
case mailboxDrafts:
attr = imapspecialuse.Drafts
fallbackNames = []string{"Draft", "Drafts"}
}
var attrMatched bool
var best *imap.MailboxInfo
for mbox := range ch {
for _, a := range mbox.Attributes {
if attr == a {
best = mbox
attrMatched = true
break
}
}
if attrMatched {
break
}
for _, fallback := range fallbackNames {
if strings.EqualFold(fallback, mbox.Name) {
best = mbox
break
}
}
}
if err := <-done; err != nil {
return nil, fmt.Errorf("failed to get mailbox with attribute %q: %v", attr, err)
}
if best == nil {
return nil, nil
}
return &MailboxInfo{best}, 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
Mailbox string
}
func (msg *IMAPMessage) URL() *url.URL {
return &url.URL{
Path: fmt.Sprintf("/message/%v/%v", url.PathEscape(msg.Mailbox), msg.Uid),
}
}
func newIMAPPartNode(msg *IMAPMessage, path []int, part *imap.BodyStructure) *IMAPPartNode {
filename, _ := part.Filename()
return &IMAPPartNode{
Path: path,
MIMEType: strings.ToLower(part.MIMEType + "/" + part.MIMESubType),
Filename: filename,
Message: msg,
}
}
func (msg *IMAPMessage) TextPart() *IMAPPartNode {
if msg.BodyStructure == nil {
return nil
}
var best *IMAPPartNode
isTextPlain := false
msg.BodyStructure.Walk(func(path []int, part *imap.BodyStructure) bool {
if !strings.EqualFold(part.MIMEType, "text") {
return true
}
if part.Disposition != "" && !strings.EqualFold(part.Disposition, "inline") {
return true
}
switch strings.ToLower(part.MIMESubType) {
case "plain":
isTextPlain = true
best = newIMAPPartNode(msg, path, part)
case "html":
if !isTextPlain {
best = newIMAPPartNode(msg, path, part)
}
}
return true
})
return best
}
func (msg *IMAPMessage) Attachments() []IMAPPartNode {
if msg.BodyStructure == nil {
return nil
}
var attachments []IMAPPartNode
msg.BodyStructure.Walk(func(path []int, part *imap.BodyStructure) bool {
if !strings.EqualFold(part.Disposition, "attachment") {
return true
}
attachments = append(attachments, *newIMAPPartNode(msg, path, part))
return true
})
return attachments
}
func pathsEqual(a, b []int) bool {
if len(a) != len(b) {
return false
}
for i := range a {
if a[i] != b[i] {
return false
}
}
return true
}
func (msg *IMAPMessage) PartByPath(path []int) *IMAPPartNode {
if msg.BodyStructure == nil {
return nil
}
if len(path) == 0 {
return newIMAPPartNode(msg, nil, msg.BodyStructure)
}
var result *IMAPPartNode
msg.BodyStructure.Walk(func(p []int, part *imap.BodyStructure) bool {
if result == nil && pathsEqual(path, p) {
result = newIMAPPartNode(msg, p, part)
}
return result == nil
})
return result
}
func (msg *IMAPMessage) PartByID(id string) *IMAPPartNode {
if msg.BodyStructure == nil || id == "" {
return nil
}
var result *IMAPPartNode
msg.BodyStructure.Walk(func(path []int, part *imap.BodyStructure) bool {
if result == nil && part.Id == "<"+id+">" {
result = newIMAPPartNode(msg, path, part)
}
return result == nil
})
return result
}
type IMAPPartNode struct {
Path []int
MIMEType string
Filename string
Children []IMAPPartNode
Message *IMAPMessage
}
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) URL(raw bool) *url.URL {
u := node.Message.URL()
if raw {
u.Path += "/raw"
}
q := u.Query()
q.Set("part", node.PathString())
u.RawQuery = q.Encode()
return u
}
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(msg *IMAPMessage, 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)),
Message: msg,
}
for i, part := range bs.Parts {
num := i + 1
partPath := append([]int(nil), path...)
partPath = append(partPath, num)
node.Children[i] = *imapPartTree(msg, part, partPath)
}
return node
}
func (msg *IMAPMessage) PartTree() *IMAPPartNode {
if msg.BodyStructure == nil {
return nil
}
return imapPartTree(msg, msg.BodyStructure, nil)
}
func (msg *IMAPMessage) HasFlag(flag string) bool {
for _, f := range msg.Flags {
if imap.CanonicalFlag(f) == flag {
return true
}
}
return false
}
func listMessages(conn *imapclient.Client, mboxName string, page, messagesPerPage 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
}
var seqSet imap.SeqSet
seqSet.AddRange(uint32(from), uint32(to))
fetch := []imap.FetchItem{imap.FetchFlags, 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, mboxName})
}
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 searchCriteriaHeader(k, v string) *imap.SearchCriteria {
return &imap.SearchCriteria{
Header: map[string][]string{
k: []string{v},
},
}
}
func searchCriteriaOr(criteria ...*imap.SearchCriteria) *imap.SearchCriteria {
or := criteria[0]
for _, c := range criteria[1:] {
or = &imap.SearchCriteria{
Or: [][2]*imap.SearchCriteria{{or, c}},
}
}
return or
}
func searchMessages(conn *imapclient.Client, mboxName, query string, page, messagesPerPage int) (msgs []IMAPMessage, total int, err error) {
if err := ensureMailboxSelected(conn, mboxName); err != nil {
return nil, 0, err
}
// TODO: full-text search on demand (can be slow)
//criteria := &imap.SearchCriteria{Text: []string{query}}
criteria := searchCriteriaOr(
searchCriteriaHeader("From", query),
searchCriteriaHeader("To", query),
searchCriteriaHeader("Cc", query),
searchCriteriaHeader("Subject", query),
)
nums, err := conn.Search(criteria)
if err != nil {
return nil, 0, fmt.Errorf("UID SEARCH failed: %v", err)
}
total = len(nums)
from := page * messagesPerPage
to := from + messagesPerPage
if from >= len(nums) {
return nil, total, nil
}
if to > len(nums) {
to = len(nums)
}
nums = nums[from:to]
indexes := make(map[uint32]int)
for i, num := range nums {
indexes[num] = i
}
var seqSet imap.SeqSet
seqSet.AddNum(nums...)
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, len(nums))
for msg := range ch {
i, ok := indexes[msg.SeqNum]
if !ok {
continue
}
msgs[i] = IMAPMessage{msg, mboxName}
}
if err := <-done; err != nil {
return nil, 0, fmt.Errorf("failed to fetch message list: %v", err)
}
return msgs, total, 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
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,
imap.FetchFlags,
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, mboxName}, part, nil
}
func markMessageAnswered(conn *imapclient.Client, mboxName string, uid uint32) error {
if err := ensureMailboxSelected(conn, mboxName); err != nil {
return err
}
seqSet := new(imap.SeqSet)
seqSet.AddNum(uid)
item := imap.FormatFlagsOp(imap.AddFlags, true)
flags := []interface{}{imap.AnsweredFlag}
return conn.UidStore(seqSet, item, flags, nil)
}
func appendMessage(c *imapclient.Client, msg *OutgoingMessage, mboxType mailboxType) (saved bool, err error) {
mbox, err := getMailboxByType(c, mboxType)
if err != nil {
return false, err
}
if mbox == nil {
return false, nil
}
// IMAP needs to know in advance the final size of the message, so
// there's no way around storing it in a buffer here.
var buf bytes.Buffer
if err := msg.WriteTo(&buf); err != nil {
return false, err
}
flags := []string{imap.SeenFlag}
if mboxType == mailboxDrafts {
flags = append(flags, imap.DraftFlag)
}
if err := c.Append(mbox.Name, flags, time.Now(), &buf); err != nil {
return false, err
}
return true, nil
}
func deleteMessage(c *imapclient.Client, mboxName string, uid uint32) error {
if err := ensureMailboxSelected(c, mboxName); err != nil {
return err
}
seqSet := new(imap.SeqSet)
seqSet.AddNum(uid)
item := imap.FormatFlagsOp(imap.AddFlags, true)
flags := []interface{}{imap.DeletedFlag}
if err := c.UidStore(seqSet, item, flags, nil); err != nil {
return err
}
return c.Expunge(nil)
}