Update webhook messages via new endpoint (discord)

When using the webhook, the previous method to edit a message was to
delete the old one via the classical API, and to create a new message
via the webhook. While this works, this means that editing "old" messages
lead to a mess where the chronological order is no longer respected.

This uses an hidden API explained in https://support.discord.com/hc/en-us/community/posts/360034557771
to achieve a proper edition using the webhook API.

The obvious downside of this approach is that since it is an
undocumented API for now, so there is no stability guarantee :/
This commit is contained in:
Simon THOBY 2020-11-14 05:08:09 +01:00 committed by GitHub
parent 765e00c949
commit cbb46293ab
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 17 additions and 56 deletions

View File

@ -34,8 +34,6 @@ type Bdiscord struct {
membersMutex sync.RWMutex
userMemberMap map[string]*discordgo.Member
nickMemberMap map[string]*discordgo.Member
webhookCache map[string]string
webhookMutex sync.RWMutex
}
func New(cfg *bridge.Config) bridge.Bridger {
@ -43,7 +41,6 @@ func New(cfg *bridge.Config) bridge.Bridger {
b.userMemberMap = make(map[string]*discordgo.Member)
b.nickMemberMap = make(map[string]*discordgo.Member)
b.channelInfoMap = make(map[string]*config.ChannelInfo)
b.webhookCache = make(map[string]string)
if b.GetString("WebhookURL") != "" {
b.Log.Debug("Configuring Discord Incoming Webhook")
b.webhookID, b.webhookToken = b.splitURL(b.GetString("WebhookURL"))
@ -191,8 +188,6 @@ func (b *Bdiscord) JoinChannel(channel config.ChannelInfo) error {
func (b *Bdiscord) Send(msg config.Message) (string, error) {
b.Log.Debugf("=> Receiving %#v", msg)
origMsgID := msg.ID
channelID := b.getChannelID(msg.Channel)
if channelID == "" {
return "", fmt.Errorf("Could not find channelID for %v", msg.Channel)
@ -233,18 +228,6 @@ func (b *Bdiscord) Send(msg config.Message) (string, error) {
return "", nil
}
// If we are editing a message, delete the old message
if msg.ID != "" {
msg.ID = b.getCacheID(msg.ID)
b.Log.Debugf("Deleting edited webhook message")
err := b.c.ChannelMessageDelete(channelID, msg.ID)
if err != nil {
b.Log.Errorf("Could not delete edited webhook message: %s", err)
}
}
b.Log.Debugf("Broadcasting using Webhook")
// skip empty messages
if msg.Text == "" && (msg.Extra == nil || len(msg.Extra["file"]) == 0) {
b.Log.Debugf("Skipping empty message %#v", msg)
@ -257,11 +240,25 @@ func (b *Bdiscord) Send(msg config.Message) (string, error) {
if len(msg.Username) > 32 {
msg.Username = msg.Username[0:32]
}
if msg.ID != "" {
b.Log.Debugf("Editing webhook message")
uri := discordgo.EndpointWebhookToken(wID, wToken) + "/messages/" + msg.ID
_, err := b.c.RequestWithBucketID("PATCH", uri, discordgo.WebhookParams{
Content: msg.Text,
Username: msg.Username,
}, discordgo.EndpointWebhookToken("", ""))
if err == nil {
return msg.ID, nil
}
b.Log.Errorf("Could not edit webhook message: %s", err)
}
b.Log.Debugf("Broadcasting using Webhook")
// if we have a global webhook for this Discord account, and permission
// to modify webhooks (previously verified), then set its channel to
// the message channel before using it
// TODO: this isn't necessary if the last message from this webhook was
// sent to the current channel
// the message channel before using it.
if isGlobalWebhook && b.canEditWebhooks {
b.Log.Debugf("Setting webhook channel to \"%s\"", msg.Channel)
_, err := b.c.WebhookEdit(wID, "", "", channelID)
@ -280,7 +277,6 @@ func (b *Bdiscord) Send(msg config.Message) (string, error) {
return "", nil
}
b.updateCacheID(origMsgID, msg.ID)
return msg.ID, nil
}
@ -291,7 +287,6 @@ func (b *Bdiscord) Send(msg config.Message) (string, error) {
if msg.ID == "" {
return "", nil
}
msg.ID = b.getCacheID(msg.ID)
err := b.c.ChannelMessageDelete(channelID, msg.ID)
return "", err
}

View File

@ -209,40 +209,6 @@ func (b *Bdiscord) splitURL(url string) (string, string) {
return webhookURLSplit[webhookIdxID], webhookURLSplit[webhookIdxToken]
}
// getcacheID tries to find a corresponding msgID in the webhook cache.
// if not found returns the original request.
func (b *Bdiscord) getCacheID(msgID string) string {
b.webhookMutex.RLock()
defer b.webhookMutex.RUnlock()
for k, v := range b.webhookCache {
if msgID == k {
return v
}
}
return msgID
}
// updateCacheID updates the cache so that the newID takes the place of
// the original ID. This is used for edit/deletes in combination with webhooks
// as editing a message via webhook means deleting the message and creating a
// new message (with a new ID). This ID needs to be set instead of the original ID
func (b *Bdiscord) updateCacheID(origID, newID string) {
b.webhookMutex.Lock()
match := false
for k, v := range b.webhookCache {
if v == origID {
delete(b.webhookCache, k)
b.webhookCache[origID] = newID
match = true
continue
}
}
if !match && origID != "" {
b.webhookCache[origID] = newID
}
b.webhookMutex.Unlock()
}
func enumerateUsernames(s string) []string {
onlySpace := true
for _, r := range s {