Move try/except from connectBroker to runConnect, so vanilla connect()

will throw an exception on error. We change the initial state for
new contexts to Disconnected to simplify the logic in runConnect()
slightly

Author: srd424

nmqtt.nim

@@ -1062,36 +1062,40 @@ proc connectBroker(ctx: MqttCtx) {.async.} =
 
   if ctx.verbosity >= 1:
     ctx.dbg "Connecting to " & ctx.host & ":" & $ctx.port
-  try:
-    ctx.s = await asyncnet.dial(ctx.host, ctx.port)
-    if ctx.sslOn:
-      when defined(ssl):
-        ctx.ssl = newContext(protSSLv23, CVerifyNone, ctx.sslCert, ctx.sslKey)
-        wrapConnectedSocket(ctx.ssl, ctx.s, handshakeAsClient)
-      else:
-        ctx.wrn "Requested SSL session but ssl is not enabled"
-        await ctx.close("SSL not enabled")
-        ctx.state = Error
-    let ok = await ctx.sendConnect()
-    if ok:
-      asyncCheck ctx.runRx()
-      asyncCheck ctx.runPing()
-  except OSError as e:
-    if ctx.verbosity >= 1 or not ctx.beenConnected:
-      ctx.dbg "Error connecting to " & ctx.host
-    if ctx.verbosity >= 2:
-      echo e.msg
-    ctx.state = Error
+
+  ctx.state = Error # set to Connecting by sendConnect
+
+  ctx.s = await asyncnet.dial(ctx.host, ctx.port)
+  if ctx.sslOn:
+    when defined(ssl):
+      ctx.ssl = newContext(protSSLv23, CVerifyNone, ctx.sslCert, ctx.sslKey)
+      wrapConnectedSocket(ctx.ssl, ctx.s, handshakeAsClient)
+    else:
+      ctx.wrn "Requested SSL session but ssl is not enabled"
+      await ctx.close("SSL not enabled")
+
+  let ok = await ctx.sendConnect()
+  if ok:
+    asyncCheck ctx.runRx()
+    asyncCheck ctx.runPing()
+
 
 proc runConnect(ctx: MqttCtx) {.async.} =
   ## Auto-connect and reconnect to broker
-  await ctx.connectBroker()
 
   while true:
     if ctx.state == Disabled:
       break
     elif ctx.state in [Disconnected, Error]:
-      await ctx.connectBroker()
+      try:
+        await ctx.connectBroker()
+      except OSError as e:
+        if ctx.verbosity >= 1 or not ctx.beenConnected:
+          ctx.dbg "Error connecting to " & ctx.host
+        if ctx.verbosity >= 2:
+          echo e.msg
+        ctx.state = Error
+
       # If the client has been disconnect, it is necessary to tell the broker,
       # that we still want to be Subscribed. PubCallbacks still holds the
       # callbacks, but we need to re-Subscribe to the broker.
@@ -1111,7 +1115,7 @@ proc runConnect(ctx: MqttCtx) {.async.} =
 
 proc newMqttCtx*(clientId: string): MqttCtx =
   ## Initiate a new MQTT client
-  MqttCtx(clientId: clientId)
+  MqttCtx(clientId: clientId, state: Disconnected)
 
 proc set_ping_interval*(ctx: MqttCtx, txInterval: int = 60) =
   ## Set the clients ping interval in seconds. Default is 60 seconds.