Add maildir backend worker

Add the initial implementation of a backend for Maildir accounts. Much
of the functionality required is implemented in the go-message and
go-maildir libraries, so we use them as much as possible.

The maildir worker hooks into a new maildir:// URL scheme in the
accounts.conf file which points to a container of several maildir
directories. From there, the OpenDirectory, FetchDirectoryContents, etc
messages work on subdirectories. This is implemented as a Container
struct which handles mapping between the symbolic email folder names and
UIDs to the concrete directories and file names.
This commit is contained in:
Ben Burwell 2019-07-11 09:44:51 -04:00 committed by Drew DeVault
parent d7cd35e72b
commit 1b8b6e218c
6 changed files with 786 additions and 0 deletions

1
go.mod
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@ -10,6 +10,7 @@ require (
github.com/ddevault/go-libvterm v0.0.0-20190526194226-b7d861da3810
github.com/emersion/go-imap v1.0.0-beta.6
github.com/emersion/go-imap-idle v0.0.0-20190519112320-2704abd7050e
github.com/emersion/go-maildir v0.0.0-20190505155239-cec913e0802c
github.com/emersion/go-message v0.10.3
github.com/emersion/go-sasl v0.0.0-20190704090222-36b50694675c
github.com/emersion/go-smtp v0.11.1

2
go.sum
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@ -23,6 +23,8 @@ github.com/emersion/go-imap v1.0.0-beta.6 h1:x1Mco8GTkkw2+1/YHasok0pWrQLpgwJVG07
github.com/emersion/go-imap v1.0.0-beta.6/go.mod h1:ORBuwFXdwt9QrAOecJPpirG6j9mao9wMfHIkd0EZfdo=
github.com/emersion/go-imap-idle v0.0.0-20190519112320-2704abd7050e h1:L7bswVJZcf2YHofgom49oFRwVqmBj/qZqDy9/SJpZMY=
github.com/emersion/go-imap-idle v0.0.0-20190519112320-2704abd7050e/go.mod h1:o14zPKCmEH5WC1vU5SdPoZGgNvQx7zzKSnxPQlobo78=
github.com/emersion/go-maildir v0.0.0-20190505155239-cec913e0802c h1:Rx3zrFK2haYD5dHh2kF937k6psgyLB6u8GgLjdDv+hw=
github.com/emersion/go-maildir v0.0.0-20190505155239-cec913e0802c/go.mod h1:GnCg8DiGPgjPjAW4qqrCJDTHYflFCe5bvLE+lJ6TLwI=
github.com/emersion/go-message v0.10.3 h1:4pajGb3Rq+gHLfRcWysgcwtGRNgLpB8LC6X/vRZ89d0=
github.com/emersion/go-message v0.10.3/go.mod h1:3h+HsGTCFHmk4ngJ2IV/YPhdlaOcR6hcgqM3yca9v7c=
github.com/emersion/go-sasl v0.0.0-20161116183048-7e096a0a6197 h1:rDJPbyliyym8ZL/Wt71kdolp6yaD4fLIQz638E6JEt0=

105
worker/maildir/container.go Normal file
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@ -0,0 +1,105 @@
package maildir
import (
"fmt"
"io/ioutil"
"log"
"path/filepath"
"sort"
"github.com/emersion/go-maildir"
"git.sr.ht/~sircmpwn/aerc/lib/uidstore"
)
// A Container is a directory which contains other directories which adhere to
// the Maildir spec
type Container struct {
dir string
log *log.Logger
uids *uidstore.Store
}
// NewContainer creates a new container at the specified directory
// TODO: return an error if the provided directory is not accessible
func NewContainer(dir string, l *log.Logger) *Container {
return &Container{dir: dir, uids: uidstore.NewStore(), log: l}
}
// ListFolders returns a list of maildir folders in the container
func (c *Container) ListFolders() ([]string, error) {
files, err := ioutil.ReadDir(c.dir)
if err != nil {
return nil, fmt.Errorf("error reading folders: %v", err)
}
dirnames := []string{}
for _, f := range files {
if f.IsDir() {
dirnames = append(dirnames, f.Name())
}
}
return dirnames, nil
}
// OpenDirectory opens an existing maildir in the container by name, moves new
// messages into cur, and registers the new keys in the UIDStore.
func (c *Container) OpenDirectory(name string) (maildir.Dir, error) {
dir := c.Dir(name)
keys, err := dir.Unseen()
if err != nil {
return dir, err
}
for _, key := range keys {
c.uids.GetOrInsert(key)
}
return dir, nil
}
// Dir returns a maildir.Dir with the specified name inside the container
func (c *Container) Dir(name string) maildir.Dir {
return maildir.Dir(filepath.Join(c.dir, name))
}
// UIDs fetches the unique message identifiers for the maildir
func (c *Container) UIDs(d maildir.Dir) ([]uint32, error) {
keys, err := d.Keys()
if err != nil {
return nil, fmt.Errorf("could not get keys for %s: %v", d, err)
}
sort.Strings(keys)
var uids []uint32
for _, key := range keys {
uids = append(uids, c.uids.GetOrInsert(key))
}
return uids, nil
}
// Message returns a Message struct for the given UID and maildir
func (c *Container) Message(d maildir.Dir, uid uint32) (*Message, error) {
if key, ok := c.uids.GetKey(uid); ok {
return &Message{
dir: d,
uid: uid,
key: key,
}, nil
}
return nil, fmt.Errorf("could not find message with uid %d in maildir %s",
uid, d)
}
// DeleteAll deletes a set of messages by UID and returns the subset of UIDs
// which were successfully deleted, stopping upon the first error.
func (c *Container) DeleteAll(d maildir.Dir, uids []uint32) ([]uint32, error) {
var success []uint32
for _, uid := range uids {
msg, err := c.Message(d, uid)
if err != nil {
return success, err
}
if err := msg.Remove(); err != nil {
return success, err
}
success = append(success, uid)
}
return success, nil
}

322
worker/maildir/message.go Normal file
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@ -0,0 +1,322 @@
package maildir
import (
"bytes"
"encoding/base64"
"fmt"
"io"
"io/ioutil"
"mime/quotedprintable"
gomail "net/mail"
"strings"
"github.com/emersion/go-maildir"
"github.com/emersion/go-message"
_ "github.com/emersion/go-message/charset"
"github.com/emersion/go-message/mail"
"git.sr.ht/~sircmpwn/aerc/models"
)
// A Message is an individual email inside of a maildir.Dir.
type Message struct {
dir maildir.Dir
uid uint32
key string
}
// NewReader reads a message into memory and returns an io.Reader for it.
func (m Message) NewReader() (io.Reader, error) {
f, err := m.dir.Open(m.key)
if err != nil {
return nil, err
}
defer f.Close()
b, err := ioutil.ReadAll(f)
if err != nil {
return nil, err
}
return bytes.NewReader(b), nil
}
// Flags fetches the set of flags currently applied to the message.
func (m Message) Flags() ([]maildir.Flag, error) {
return m.dir.Flags(m.key)
}
// SetFlags replaces the message's flags with a new set.
func (m Message) SetFlags(flags []maildir.Flag) error {
return m.dir.SetFlags(m.key, flags)
}
// MarkRead either adds or removes the maildir.FlagSeen flag from the message.
func (m Message) MarkRead(seen bool) error {
flags, err := m.Flags()
if err != nil {
return fmt.Errorf("could not read previous flags: %v", err)
}
if seen {
flags = append(flags, maildir.FlagSeen)
return m.SetFlags(flags)
}
var newFlags []maildir.Flag
for _, flag := range flags {
if flag != maildir.FlagSeen {
newFlags = append(newFlags, flag)
}
}
return m.SetFlags(newFlags)
}
// Remove deletes the email immediately.
func (m Message) Remove() error {
return m.dir.Remove(m.key)
}
// MessageInfo populates a models.MessageInfo struct for the message.
func (m Message) MessageInfo() (*models.MessageInfo, error) {
f, err := m.dir.Open(m.key)
if err != nil {
return nil, err
}
defer f.Close()
msg, err := message.Read(f)
if err != nil {
return nil, fmt.Errorf("could not read message: %v", err)
}
bs, err := parseEntityStructure(msg)
if err != nil {
return nil, fmt.Errorf("could not get structure: %v", err)
}
env, err := parseEnvelope(&msg.Header)
if err != nil {
return nil, fmt.Errorf("could not get envelope: %v", err)
}
flags, err := m.Flags()
if err != nil {
return nil, fmt.Errorf("could not read flags: %v", err)
}
return &models.MessageInfo{
BodyStructure: bs,
Envelope: env,
Flags: translateFlags(flags),
InternalDate: env.Date,
RFC822Headers: &mail.Header{msg.Header},
Size: 0,
Uid: m.uid,
}, nil
}
// NewBodyPartReader creates a new io.Reader for the requested body part(s) of
// the message.
func (m Message) NewBodyPartReader(requestedParts []int) (io.Reader, error) {
f, err := m.dir.Open(m.key)
if err != nil {
return nil, err
}
defer f.Close()
msg, err := message.Read(f)
if err != nil {
return nil, fmt.Errorf("could not read message: %v", err)
}
return fetchEntityPartReader(msg, requestedParts)
}
func fetchEntityPartReader(e *message.Entity, index []int) (io.Reader, error) {
if len(index) < 1 {
return nil, fmt.Errorf("no part to read")
}
if mpr := e.MultipartReader(); mpr != nil {
idx := 0
for {
idx++
part, err := mpr.NextPart()
if err != nil {
return nil, err
}
if idx == index[0] {
rest := index[1:]
if len(rest) < 1 {
return fetchEntityReader(part)
}
return fetchEntityPartReader(part, index[1:])
}
}
}
if index[0] != 1 {
return nil, fmt.Errorf("cannont return non-first part of non-multipart")
}
return fetchEntityReader(e)
}
// fetchEntityReader makes an io.Reader for the given entity. Since the
// go-message package decodes the body for us, and the UI expects to deal with
// a reader whose bytes are encoded with the part's encoding, we are in the
// interesting position of needing to re-encode the reader before sending it
// off to the UI layer.
//
// TODO: probably change the UI to expect an already-decoded reader and decode
// in the IMAP worker.
func fetchEntityReader(e *message.Entity) (io.Reader, error) {
enc := e.Header.Get("content-transfer-encoding")
var buf bytes.Buffer
// base64
if strings.EqualFold(enc, "base64") {
wc := base64.NewEncoder(base64.StdEncoding, &buf)
defer wc.Close()
if _, err := io.Copy(wc, e.Body); err != nil {
return nil, fmt.Errorf("could not base64 encode: %v", err)
}
return &buf, nil
}
// quoted-printable
if strings.EqualFold(enc, "quoted-printable") {
wc := quotedprintable.NewWriter(&buf)
defer wc.Close()
if _, err := io.Copy(wc, e.Body); err != nil {
return nil, fmt.Errorf("could not quoted-printable encode: %v", err)
}
return &buf, nil
}
// other general encoding
if _, err := io.Copy(&buf, e.Body); err != nil {
return nil, err
}
return &buf, nil
}
// split a MIME type into its major and minor parts
func splitMIME(m string) (string, string) {
parts := strings.Split(m, "/")
if len(parts) != 2 {
return parts[0], ""
}
return parts[0], parts[1]
}
func parseEntityStructure(e *message.Entity) (*models.BodyStructure, error) {
var body models.BodyStructure
contentType, ctParams, err := e.Header.ContentType()
if err != nil {
return nil, fmt.Errorf("could not parse content type: %v", err)
}
mimeType, mimeSubType := splitMIME(contentType)
body.MIMEType = mimeType
body.MIMESubType = mimeSubType
body.Params = ctParams
body.Description = e.Header.Get("content-description")
body.Encoding = e.Header.Get("content-transfer-encoding")
if cd := e.Header.Get("content-disposition"); cd != "" {
contentDisposition, cdParams, err := e.Header.ContentDisposition()
if err != nil {
return nil, fmt.Errorf("could not parse content disposition: %v", err)
}
body.Disposition = contentDisposition
body.DispositionParams = cdParams
}
body.Parts = []*models.BodyStructure{}
if mpr := e.MultipartReader(); mpr != nil {
for {
part, err := mpr.NextPart()
if err == io.EOF {
return &body, nil
} else if err != nil {
return nil, err
}
ps, err := parseEntityStructure(part)
if err != nil {
return nil, fmt.Errorf("could not parse child entity structure: %v", err)
}
body.Parts = append(body.Parts, ps)
}
}
return &body, nil
}
func parseEnvelope(h *message.Header) (*models.Envelope, error) {
date, err := gomail.ParseDate(h.Get("date"))
if err != nil {
return nil, fmt.Errorf("could not parse date header: %v", err)
}
from, err := parseAddressList(h, "from")
if err != nil {
return nil, fmt.Errorf("could not read from address: %v", err)
}
to, err := parseAddressList(h, "to")
if err != nil {
return nil, fmt.Errorf("could not read to address: %v", err)
}
cc, err := parseAddressList(h, "cc")
if err != nil {
return nil, fmt.Errorf("could not read cc address: %v", err)
}
bcc, err := parseAddressList(h, "bcc")
if err != nil {
return nil, fmt.Errorf("could not read bcc address: %v", err)
}
return &models.Envelope{
Date: date,
Subject: h.Get("subject"),
MessageId: h.Get("message-id"),
From: from,
To: to,
Cc: cc,
Bcc: bcc,
}, nil
}
func parseAddressList(h *message.Header, key string) ([]*models.Address, error) {
var converted []*models.Address
hdr := h.Get(key)
if strings.TrimSpace(hdr) == "" {
return converted, nil
}
addrs, err := gomail.ParseAddressList(hdr)
if err != nil {
if strings.Index(hdr, "@") < 0 {
return []*models.Address{&models.Address{
Name: hdr,
}}, nil
}
return nil, err
}
for _, addr := range addrs {
parts := strings.Split(addr.Address, "@")
var mbox, host string
if len(parts) > 1 {
mbox = strings.Join(parts[0:len(parts)-1], "@")
host = parts[len(parts)-1]
} else {
mbox = addr.Address
}
converted = append(converted, &models.Address{
Name: addr.Name,
Mailbox: mbox,
Host: host,
})
}
return converted, nil
}
var flagMap = map[maildir.Flag]models.Flag{
maildir.FlagReplied: models.AnsweredFlag,
maildir.FlagSeen: models.SeenFlag,
maildir.FlagTrashed: models.DeletedFlag,
maildir.FlagFlagged: models.FlaggedFlag,
// maildir.FlagDraft Flag = 'D'
// maildir.FlagPassed Flag = 'P'
}
func translateFlags(maildirFlags []maildir.Flag) []models.Flag {
var flags []models.Flag
for _, maildirFlag := range maildirFlags {
if flag, ok := flagMap[maildirFlag]; ok {
flags = append(flags, flag)
}
}
return flags
}

353
worker/maildir/worker.go Normal file
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@ -0,0 +1,353 @@
package maildir
import (
"fmt"
"io"
"net/url"
"os"
"path/filepath"
"github.com/emersion/go-maildir"
"git.sr.ht/~sircmpwn/aerc/models"
"git.sr.ht/~sircmpwn/aerc/worker/types"
)
var errUnsupported = fmt.Errorf("unsupported command")
// A Worker handles interfacing between aerc's UI and a group of maildirs.
type Worker struct {
c *Container
selected *maildir.Dir
worker *types.Worker
}
// NewWorker creates a new maildir worker with the provided worker.
func NewWorker(worker *types.Worker) *Worker {
return &Worker{worker: worker}
}
// Run starts the worker's message handling loop.
func (w *Worker) Run() {
for {
action := <-w.worker.Actions
msg := w.worker.ProcessAction(action)
if err := w.handleMessage(msg); err == errUnsupported {
w.worker.PostMessage(&types.Unsupported{
Message: types.RespondTo(msg),
}, nil)
} else if err != nil {
w.worker.PostMessage(&types.Error{
Message: types.RespondTo(msg),
Error: err,
}, nil)
}
}
}
func (w *Worker) done(msg types.WorkerMessage) {
w.worker.PostMessage(&types.Done{types.RespondTo(msg)}, nil)
}
func (w *Worker) err(msg types.WorkerMessage, err error) {
w.worker.PostMessage(&types.Error{
Message: types.RespondTo(msg),
Error: err,
}, nil)
}
func (w *Worker) handleMessage(msg types.WorkerMessage) error {
switch msg := msg.(type) {
case *types.Unsupported:
// No-op
case *types.Configure:
return w.handleConfigure(msg)
case *types.Connect:
return w.handleConnect(msg)
case *types.ListDirectories:
return w.handleListDirectories(msg)
case *types.OpenDirectory:
return w.handleOpenDirectory(msg)
case *types.FetchDirectoryContents:
return w.handleFetchDirectoryContents(msg)
case *types.CreateDirectory:
return w.handleCreateDirectory(msg)
case *types.FetchMessageHeaders:
return w.handleFetchMessageHeaders(msg)
case *types.FetchMessageBodyPart:
return w.handleFetchMessageBodyPart(msg)
case *types.FetchFullMessages:
return w.handleFetchFullMessages(msg)
case *types.DeleteMessages:
return w.handleDeleteMessages(msg)
case *types.ReadMessages:
return w.handleReadMessages(msg)
case *types.CopyMessages:
return w.handleCopyMessages(msg)
case *types.AppendMessage:
return w.handleAppendMessage(msg)
case *types.SearchDirectory:
return w.handleSearchDirectory(msg)
}
return errUnsupported
}
func (w *Worker) handleConfigure(msg *types.Configure) error {
defer w.done(msg)
u, err := url.Parse(msg.Config.Source)
if err != nil {
w.worker.Logger.Printf("error configuring maildir worker: %v", err)
return err
}
dir := u.Path
if u.Host == "~" {
home, err := os.UserHomeDir()
if err != nil {
return fmt.Errorf("could not resolve home directory: %v", err)
}
dir = filepath.Join(home, u.Path)
}
w.c = NewContainer(dir, w.worker.Logger)
w.worker.Logger.Printf("configured base maildir: %s", dir)
return nil
}
func (w *Worker) handleConnect(msg *types.Connect) error {
w.done(msg)
return nil
}
func (w *Worker) handleListDirectories(msg *types.ListDirectories) error {
defer w.done(msg)
dirs, err := w.c.ListFolders()
if err != nil {
w.worker.Logger.Printf("error listing directories: %v", err)
return err
}
for _, name := range dirs {
w.worker.PostMessage(&types.Directory{
Message: types.RespondTo(msg),
Dir: &models.Directory{
Name: name,
Attributes: []string{},
},
}, nil)
}
return nil
}
func (w *Worker) handleOpenDirectory(msg *types.OpenDirectory) error {
defer w.done(msg)
w.worker.Logger.Printf("opening %s", msg.Directory)
dir, err := w.c.OpenDirectory(msg.Directory)
if err != nil {
return err
}
w.selected = &dir
// TODO: why does this need to be sent twice??
info := &types.DirectoryInfo{
Info: &models.DirectoryInfo{
Name: msg.Directory,
Flags: []string{},
ReadOnly: false,
// total messages
Exists: 0,
// new messages since mailbox was last opened
Recent: 0,
// total unread
Unseen: 0,
},
}
w.worker.PostMessage(info, nil)
w.worker.PostMessage(info, nil)
return nil
}
func (w *Worker) handleFetchDirectoryContents(
msg *types.FetchDirectoryContents) error {
defer w.done(msg)
uids, err := w.c.UIDs(*w.selected)
if err != nil {
w.worker.Logger.Printf("error scanning uids: %v", err)
return err
}
w.worker.PostMessage(&types.DirectoryContents{
Message: types.RespondTo(msg),
Uids: uids,
}, nil)
return nil
}
func (w *Worker) handleCreateDirectory(msg *types.CreateDirectory) error {
dir := w.c.Dir(msg.Directory)
defer w.done(msg)
if err := dir.Create(); err != nil {
w.worker.Logger.Printf("could not create directory %s: %v",
msg.Directory, err)
return err
}
return nil
}
func (w *Worker) handleFetchMessageHeaders(
msg *types.FetchMessageHeaders) error {
defer w.done(msg)
for _, uid := range msg.Uids {
m, err := w.c.Message(*w.selected, uid)
if err != nil {
w.worker.Logger.Printf("could not get message: %v", err)
w.err(msg, err)
continue
}
info, err := m.MessageInfo()
if err != nil {
w.worker.Logger.Printf("could not get message info: %v", err)
w.err(msg, err)
continue
}
w.worker.PostMessage(&types.MessageInfo{
Message: types.RespondTo(msg),
Info: info,
}, nil)
}
return nil
}
func (w *Worker) handleFetchMessageBodyPart(
msg *types.FetchMessageBodyPart) error {
defer w.done(msg)
// get reader
m, err := w.c.Message(*w.selected, msg.Uid)
if err != nil {
w.worker.Logger.Printf("could not get message %d: %v", msg.Uid, err)
return err
}
r, err := m.NewBodyPartReader(msg.Part)
if err != nil {
w.worker.Logger.Printf(
"could not get body part reader for message=%d, parts=%#v: %v",
msg.Uid, msg.Part, err)
return err
}
w.worker.PostMessage(&types.MessageBodyPart{
Message: types.RespondTo(msg),
Part: &models.MessageBodyPart{
Reader: r,
Uid: msg.Uid,
},
}, nil)
// mark message as read
if err := m.MarkRead(true); err != nil {
w.worker.Logger.Printf("could not mark message as read: %v", err)
return err
}
// send updated flags to ui
info, err := m.MessageInfo()
if err != nil {
w.worker.Logger.Printf("could not fetch message info: %v", err)
return err
}
w.worker.PostMessage(&types.MessageInfo{
Message: types.RespondTo(msg),
Info: info,
}, nil)
return nil
}
func (w *Worker) handleFetchFullMessages(msg *types.FetchFullMessages) error {
defer w.done(msg)
for _, uid := range msg.Uids {
m, err := w.c.Message(*w.selected, uid)
if err != nil {
w.worker.Logger.Printf("could not get message %d: %v", uid, err)
return err
}
r, err := m.NewReader()
if err != nil {
w.worker.Logger.Printf("could not get message reader: %v", err)
return err
}
w.worker.PostMessage(&types.FullMessage{
Message: types.RespondTo(msg),
Content: &models.FullMessage{
Uid: uid,
Reader: r,
},
}, nil)
}
return nil
}
func (w *Worker) handleDeleteMessages(msg *types.DeleteMessages) error {
defer w.done(msg)
deleted, err := w.c.DeleteAll(*w.selected, msg.Uids)
if len(deleted) > 0 {
w.worker.PostMessage(&types.MessagesDeleted{
Message: types.RespondTo(msg),
Uids: deleted,
}, nil)
}
if err != nil {
w.worker.Logger.Printf("error removing some messages: %v", err)
return err
}
return nil
}
func (w *Worker) handleReadMessages(msg *types.ReadMessages) error {
defer w.done(msg)
for _, uid := range msg.Uids {
m, err := w.c.Message(*w.selected, uid)
if err != nil {
w.worker.Logger.Printf("could not get message: %v", err)
w.err(msg, err)
continue
}
if err := m.MarkRead(msg.Read); err != nil {
w.worker.Logger.Printf("could not mark message as read: %v", err)
w.err(msg, err)
continue
}
info, err := m.MessageInfo()
if err != nil {
w.worker.Logger.Printf("could not get message info: %v", err)
w.err(msg, err)
continue
}
w.worker.PostMessage(&types.MessageInfo{
Message: types.RespondTo(msg),
Info: info,
}, nil)
}
return nil
}
func (w *Worker) handleCopyMessages(msg *types.CopyMessages) error {
// TODO: this.
return nil
}
func (w *Worker) handleAppendMessage(msg *types.AppendMessage) error {
defer w.done(msg)
dest := w.c.Dir(msg.Destination)
delivery, err := dest.NewDelivery()
if err != nil {
w.worker.Logger.Printf("could not deliver message to %s: %v",
msg.Destination, err)
return err
}
defer delivery.Close()
if _, err := io.Copy(delivery, msg.Reader); err != nil {
w.worker.Logger.Printf("could not write message to destination: %v", err)
return err
}
return nil
}
func (w *Worker) handleSearchDirectory(msg *types.SearchDirectory) error {
return errUnsupported
}

View File

@ -2,6 +2,7 @@ package worker
import (
"git.sr.ht/~sircmpwn/aerc/worker/imap"
"git.sr.ht/~sircmpwn/aerc/worker/maildir"
"git.sr.ht/~sircmpwn/aerc/worker/types"
"fmt"
@ -27,6 +28,8 @@ func NewWorker(source string, logger *log.Logger) (*types.Worker, error) {
fallthrough
case "imaps":
worker.Backend = imap.NewIMAPWorker(worker)
case "maildir":
worker.Backend = maildir.NewWorker(worker)
default:
return nil, fmt.Errorf("Unknown backend %s", u.Scheme)
}