Get the gateway heartbeating.

src/client.nim

@@ -1,53 +1,98 @@
 import websocket, asyncnet, asyncdispatch, json, httpClient, strformat
 
 type
+    DiscordOpCode = enum
+        opDispatch = 0,
+        opHeartbeat = 1,
+        opIdentify = 2,
+        opPresenceUpdate = 3,
+        opVoiceStateUpdate = 4,
+        opResume = 6,
+        opReconnect = 7,
+        opRequestGuildMembers = 8,
+        opInvalidSession = 9,
+        opHello = 10,
+        opHeartbeatAck = 11
+
+
+
     DiscordClient* = ref object ## Discord Client
         token*: string
         #user*: User
         #cache: Cache
         ws: AsyncWebSocket
         httpClient: AsyncHttpClient
+        heartbeatInterval: int
+        heartbeatAcked: bool
+        lastSequence: int
 
-#[ proc heartbeat() {.async.} =
+proc sendGatewayRequest*(client: DiscordClient, request: JsonNode, msg: string = "") {.async.} =
+    if (msg.len == 0):
+        echo "Sending gateway payload: ", request
+    else:
+        echo msg
+
+    discard client.ws.sendText($request)
+
+proc handleHeartbeat(client: DiscordClient) {.async.} =
     while true:
-        await sleepAsync(35000)
-        echo "heartbeat now" ]#
+        var heartbeatPayload: JsonNode
+        if (client.lastSequence == 0):
+            heartbeatPayload = %* { "d": nil, "op": ord(DiscordOpCode.opHeartbeat) }
+        else:
+            heartbeatPayload = %* { "d": client.lastSequence, "op": ord(DiscordOpCode.opHeartbeat) }
 
-proc read(client: DiscordClient) {.async.} = 
+        await client.sendGatewayRequest(heartbeatPayload, fmt("Sending heartbeat payload: {$heartbeatPayload}"))
+        client.heartbeatAcked = true
+
+        echo "Waiting ", client.heartbeatInterval, " ms until next heartbeat..."
+        await sleepAsync(client.heartbeatInterval)
+
+proc getIdentifyPacket(client: DiscordClient): JsonNode =
+    return %* { "op": ord(DiscordOpCode.opIdentify), "d": { "token": client.token, "properties": { "$os": system.hostOS, "$browser": "NimCord", "$device": "NimCord" } } }
+
+proc handleWebsocketPacket(client: DiscordClient) {.async.} = 
     while true:
         var packet: tuple[opcode: Opcode, data: string]
 
         packet = await client.ws.readData();
-        echo "(opcode: ", packet.opcode, ", data: ", packet.data, ")"
+        echo "Received gateway payload: ", packet.data
 
         var json: JsonNode = parseJson(packet.data);
 
-        case json["op"].num
-            of 10:
-                echo "Received 'HELLO' from the gateway."
-                # Start heartbeat here!
+        if (json.contains("s")):
+            client.lastSequence = json["s"].getInt()
+
+        case json["op"].getInt()
+            of ord(DiscordOpCode.opHello):
+                client.heartbeatInterval = json["d"]["heartbeat_interval"].getInt()
+                discard client.sendGatewayRequest(client.getIdentifyPacket())
+
+                asyncCheck client.handleHeartbeat()
+                client.heartbeatAcked = true
+            of ord(DiscordOpCode.opHeartbeatAck):
+                client.heartbeatAcked = true
             else:
                 discard
             
-proc Endpoint(url: string): string =
+proc endpoint*(url: string): string =
     return fmt("https://discord.com/api/v6{url}")
 
-proc startConnection(client: DiscordClient) {.async.} =
+proc startConnection*(client: DiscordClient) {.async.} =
     client.httpClient = newAsyncHttpClient()
     client.httpClient.headers = newHttpHeaders({"Authorization": fmt("Bot {client.token}")})
 
-    let result = parseJson(await client.httpClient.getContent(Endpoint("/gateway/bot")))
-    echo "Got result: ", $result
+    let urlResult = parseJson(await client.httpClient.getContent(endpoint("/gateway/bot")))
+    echo "Got result: ", $urlResult
 
-    if (result.contains("url")):
-        let url = result["url"].getStr()
+    if (urlResult.contains("url")):
+        let url = urlResult["url"].getStr()
 
         client.ws = await newAsyncWebsocketClient(url[6..url.high], Port 443 ,
             path = "/v=6&encoding=json", true)
         echo "Connected!"
 
-        asyncCheck client.read()
-        #asyncCheck heartbeat()
+        asyncCheck client.handleWebsocketPacket()
         runForever()
     else:
         var e: ref IOError
@@ -56,5 +101,5 @@ proc startConnection(client: DiscordClient) {.async.} =
         raise e
 
 var bot = DiscordClient(token: 
-    "TOKEN")
+    "NjQ4NjcwNDA4NDg4MjU1NTAw.XtCGDw.ZNaRT6kNIMyO1wlcZbbaUGSsm7g")
 waitFor bot.startConnection()