feat: implement message retry handling

so if a message fails to decrypt on the other user's end -- it can be retried

src/Socket/messages-recv.ts

@@ -6,6 +6,7 @@ import { proto } from "../../WAProto"
 import { KEY_BUNDLE_TYPE } from "../Defaults"
 import { makeChatsSocket } from "./chats"
 import { extractGroupMetadata } from "./groups"
+import { Boom } from "@hapi/boom"
 
 const getStatusFromReceiptType = (type: string | undefined) => {
     if(type === 'read' || type === 'read-self') {
@@ -24,6 +25,7 @@ export const makeMessagesRecvSocket = (config: SocketConfig) => {
 		ev,
         authState,
 		ws,
+        assertSession,
         assertingPreKeys,
 		sendNode,
         relayMessage,
@@ -464,30 +466,64 @@ export const makeMessagesRecvSocket = (config: SocketConfig) => {
         }
     })
 
+    const sendMessagesAgain = async(key: proto.IMessageKey, ids: string[]) => {
+        const participant = key.participant || key.remoteJid
+        await assertSession(participant, true)
+
+        logger.debug({ key, ids }, 'recv retry request, forced new session')
+
+        const msgs = await Promise.all(
+            ids.map(id => (
+                config.getMessage({ ...key, id })
+            ))
+        )
+        const missingMsgIdx = msgs.findIndex(m => !m)
+        if(missingMsgIdx >= 0) {
+            throw new Boom(
+                `recv request to retry message, but message "${ids[missingMsgIdx]}" not available`, 
+                { statusCode: 404, data: { key } }
+            )
+        }
+
+        for(let i = 0; i < msgs.length;i++) {
+            await relayMessage(key.remoteJid, msgs[i], {
+                messageId: ids[i],
+                participant
+            })
+        }
+        
+    }
+
     const handleReceipt = async(node: BinaryNode) => {
         const { attrs, content } = node
-        const status = getStatusFromReceiptType(attrs.type)
+        const remoteJid = attrs.recipient || attrs.from 
+        const fromMe = attrs.recipient ? false : true
 
+        const ids = [attrs.id]
+        if(Array.isArray(content)) {
+            const items = getBinaryNodeChildren(content[0], 'item')
+            ids.push(...items.map(i => i.attrs.id))
+        }
+
+        const key: proto.IMessageKey = {
+            remoteJid,
+            id: '',
+            fromMe,
+            participant: attrs.participant
+        }
+
+        const status = getStatusFromReceiptType(attrs.type)
         if(typeof status !== 'undefined' && !areJidsSameUser(attrs.from, authState.creds.me?.id)) {
-            const ids = [attrs.id]
-            if(Array.isArray(content)) {
-                const items = getBinaryNodeChildren(content[0], 'item')
-                ids.push(...items.map(i => i.attrs.id))
-            }
-            
-            const remoteJid = attrs.recipient || attrs.from 
-            const fromMe = attrs.recipient ? false : true
             ev.emit('messages.update', ids.map(id => ({
-                key: {
-                    remoteJid,
-                    id: id,
-                    fromMe,
-                    participant: attrs.participant
-                },
+                key: { ...key, id },
                 update: { status }
             })))
         }
 
+        if(attrs.type === 'retry') {
+            await sendMessagesAgain(key, ids)
+        }
+
         await sendMessageAck(node, { class: 'receipt', type: attrs.type })
     }
 

src/Socket/messages-send.ts

@@ -238,8 +238,10 @@ export const makeMessagesSocket = (config: SocketConfig) => {
     const relayMessage = async(
         jid: string, 
         message: proto.IMessage, 
-        { messageId: msgId, additionalAttributes, cachedGroupMetadata }: MessageRelayOptions
+        { messageId: msgId, participant, additionalAttributes, cachedGroupMetadata }: MessageRelayOptions
     ) => {
+        const meId = authState.creds.me!.id
+
         const { user, server } = jidDecode(jid)
         const isGroup = server === 'g.us'
         msgId = msgId || generateMessageID()
@@ -250,16 +252,23 @@ export const makeMessagesSocket = (config: SocketConfig) => {
 
         const destinationJid = jidEncode(user, isGroup ? 'g.us' : 's.whatsapp.net')
 
+        const devices: JidWithDevice[] = []
+        if(participant) {
+            const { user, device } = jidDecode(participant)
+            devices.push({ user, device })
+        }
+
         if(isGroup) {
-            const { ciphertext, senderKeyDistributionMessageKey } = await encryptSenderKeyMsgSignalProto(destinationJid, encodedMsg, authState.creds.me!.id, authState)
+            const { ciphertext, senderKeyDistributionMessageKey } = await encryptSenderKeyMsgSignalProto(destinationJid, encodedMsg, meId, authState)
             
             let groupData = cachedGroupMetadata ? await cachedGroupMetadata(jid) : undefined 
             if(!groupData) groupData = await groupMetadata(jid)
 
-            const participantsList = groupData.participants.map(p => p.id)
-            const devices = await getUSyncDevices(participantsList, false)
-
-            logger.debug(`got ${devices.length} additional devices`)
+            if(!participant) {
+                const participantsList = groupData.participants.map(p => p.id)
+                const devices = await getUSyncDevices(participantsList, false)
+                devices.push(...devices)
+            }
 
             const encSenderKeyMsg = encodeWAMessage({
                 senderKeyDistributionMessage: {
@@ -304,7 +313,7 @@ export const makeMessagesSocket = (config: SocketConfig) => {
                 content: binaryNodeContent
             }
         } else {
-            const { user: meUser } = jidDecode(authState.creds.me!.id!)
+            const { user: meUser } = jidDecode(meId)
             
             const messageToMyself: proto.IMessage = {
                 deviceSentMessage: {
@@ -314,15 +323,13 @@ export const makeMessagesSocket = (config: SocketConfig) => {
             }
             const encodedMeMsg = encodeWAMessage(messageToMyself)
 
-            participants.push(
-                await createParticipantNode(jidEncode(user, 's.whatsapp.net'), encodedMsg)
-            )
-            participants.push(
-                await createParticipantNode(jidEncode(meUser, 's.whatsapp.net'), encodedMeMsg)
-            )
-            const devices = await getUSyncDevices([ authState.creds.me!.id!, jid ], true)
-
-            logger.debug(`got ${devices.length} additional devices`)
+            if(!participant) {
+                devices.push({ user })
+                devices.push({ user: meUser })
+                
+                const additionalDevices = await getUSyncDevices([ meId, jid ], true)
+                devices.push(...additionalDevices)
+            }
 
             for(const { user, device } of devices) {
                 const isMe = user === meUser
@@ -363,7 +370,8 @@ export const makeMessagesSocket = (config: SocketConfig) => {
                 content: proto.ADVSignedDeviceIdentity.encode(authState.creds.account).finish()
             })
         }
-        logger.debug({ msgId }, 'sending message')
+
+        logger.debug({ msgId }, `sending message to ${devices.length} devices`)
 
         await sendNode(stanza)