Fix some bugs and problems in gossip (#3527)

* Allow configuration of debugOutput to be performed

* don't send to own IP or update own data

* Use same socket to send and receive. Avoid problems in many opened and closed sockets to send

* Add callback for REMOVEed hosts

* Send broascast messages if seedList is empty

* Adapt yeelink to new luacheck rules

* Fix building of luac.cross for win to win2019 and VS 2019

Author: HHHartmann

.github/workflows/build.yml

@@ -58,7 +58,7 @@ jobs:
 
   build_luac_cross_win:
 
-    runs-on: windows-latest
+    runs-on: windows-2019
 
     steps:
     - uses: actions/checkout@v2

.gitignore

@@ -28,6 +28,8 @@ uz_zip
 
 # ignore VS Code files
 .vscode/**
+# ignore VS files
+.vs/**
 
 # ignore IDEA files
 .idea

docs/lua-modules/gossip.md

@@ -68,7 +68,7 @@ gossip.setConfig(config)
 
 Sets the configuration for gossip. The available options are:
 
-`seedList` : the list of seeds gossip will start with; this will be updated as new nodes are discovered. Note that it's enough for all nodes to start with the same IP in the seedList, as once they have one seed in common, the data will propagate
+`seedList` : the list of seeds gossip will start with; this will be updated as new nodes are discovered. Note that it's enough for all nodes to start with the same IP in the seedList, as once they have one seed in common, the data will propagate. If the seedList is empty a broadcast is sent, so this can be used for automatic discovery of nodes.
 
 `roundInterval`: interval in milliseconds at which gossip will pick a random node from the seed list and send a `SYN` request
 

lua_modules/gossip/gossip.lua

@@ -15,11 +15,7 @@ end
 
 utils.debug = function(message)
   if gossip.config.debug then
-    if gossip.config.debugOutput then
-      gossip.config.debugOutput(message);
-    else
-      print(message);
-    end
+    gossip.config.debugOutput(message);
   end
 end
 
@@ -105,15 +101,23 @@ state.start = function()
     return;
   end
 
+  -- sending to own IP makes no sense
+  for index, value in ipairs(gossip.config.seedList) do
+      if value == gossip.ip then
+          table.remove(gossip.config.seedList, index)
+          utils.debug('removing own ip from seed list')
+      end
+  end
+
   gossip.networkState[gossip.ip] = {};
   local localState = gossip.networkState[gossip.ip];
   localState.revision = state.setRev();
   localState.heartbeat = tmr.time();
   localState.state = constants.nodeState.UP;
 
-  gossip.inboundSocket = net.createUDPSocket();
-  gossip.inboundSocket:listen(gossip.config.comPort);
-  gossip.inboundSocket:on('receive', network.receiveData);
+  gossip.socket = net.createUDPSocket();
+  gossip.socket:listen(gossip.config.comPort);
+  gossip.socket:on('receive', network.receiveData);
 
   gossip.started = true;
 
@@ -128,27 +132,38 @@ end
 state.tickNodeState = function(ip)
   if gossip.networkState[ip] then
     local nodeState = gossip.networkState[ip].state;
+    local oldNodeState = nodeState;
     if nodeState < constants.nodeState.REMOVE then
       nodeState = nodeState + constants.nodeState.TICK;
       gossip.networkState[ip].state = nodeState;
     end
+    if oldNodeState == constants.nodeState.DOWN then
+      if gossip.updateCallback then gossip.updateCallback(gossip.networkState[ip]); end
+    end
   end
 end
 
 -- Network
+network.broadcastIp = "255.255.255.255"
 
 network.pushGossip = function(data, ip)
+  if not gossip.started then
+    utils.debug('Gossip not started.');
+    return;
+  end
   gossip.networkState[gossip.ip].data = data;
   network.sendSyn(nil, ip);
 end
 
 network.updateNetworkState = function(updateData)
   if gossip.updateCallback then gossip.updateCallback(updateData); end
   for ip, data in pairs(updateData) do
-    if not utils.contains(gossip.config.seedList, ip) then
+    if not utils.contains(gossip.config.seedList, ip) and ip ~= network.broadcastIp and ip ~= gossip.ip then
       table.insert(gossip.config.seedList, ip);
     end
-    gossip.networkState[ip] = data;
+    if ip ~= gossip.ip then
+      gossip.networkState[ip] = data;
+    end
   end
 end
 
@@ -170,17 +185,16 @@ network.pickRandomNode = function()
     return gossip.config.seedList[randomListPick];
   end
   utils.debug(
-      'Seedlist is empty. Please provide one or wait for node to be contacted.');
-  return nil;
+      'Seedlist is empty. Using broadcast IP '..network.broadcastIp..' to discover.');
+  return network.broadcastIp;
 end
 
 network.sendData = function(ip, data, sendType)
-  local outboundSocket = net.createUDPSocket();
-  data.type = sendType;
-  local dataToSend = sjson.encode(data);
-  data.type = nil;
-  outboundSocket:send(gossip.config.comPort, ip, dataToSend);
-  outboundSocket:close();
+  data.type = sendType
+  local dataToSend = sjson.encode(data)
+  data.type = nil
+  gossip.socket:send(gossip.config.comPort, ip, dataToSend)
+  utils.debug("Sent "..#dataToSend.." bytes")
 end
 
 network.receiveSyn = function(ip, synData)
@@ -235,7 +249,8 @@ constants.defaultConfig = {
   seedList = {},
   roundInterval = 15000,
   comPort = 5000,
-  debug = false
+  debug = false,
+  debugOutput = print
 };
 
 constants.comparisonFields = {'revision', 'heartbeat', 'state'};

lua_modules/gossip/gossip_tests.lua

@@ -24,6 +24,7 @@ file.putcontents = dummy
 
 local Ip_1 = '192.168.0.1';
 local Ip_2 = '192.168.0.2';
+local Ip_own = '192.168.0.3';
 
 -- test runner
 
@@ -186,20 +187,19 @@ function Test.utils_getMinus()
     state = constants.nodeState.SUSPECT;
   };
 
-  --local diff1 = utils.getMinus(data1, data2);
+  local diff1 = utils.getMinus(data1, data2);
   local diff2 = utils.getMinus(data2, data1);
 
-  --assert(diff1[Ip_1] ~= nil and diff1[Ip_2] == nil);
+  assert(diff1[Ip_1] ~= nil and diff1[Ip_2] == nil);
   assert(diff2[Ip_1] == nil and diff2[Ip_2] ~= nil);
-
 end
 
 -- state
 
 function Test.state_setRev()
-  gossip.ip = Ip_1;
-  gossip.networkState[Ip_1] = {};
-  gossip.networkState[Ip_1].revision = -1;
+  gossip.ip = Ip_own;
+  gossip.networkState[Ip_own] = {};
+  gossip.networkState[Ip_own].revision = -1;
   assert(state.setRev() == 0, 'Revision not initialized to 0.');
 end
 
@@ -223,6 +223,7 @@ end
 -- network
 
 function Test.network_updateNetworkState_no_callback()
+  gossip.ip = Ip_own;
   local updateData = {}
   updateData[Ip_1] = {
     revision = 1,
@@ -232,7 +233,12 @@ function Test.network_updateNetworkState_no_callback()
   updateData[Ip_2] = {
     revision = 1,
     heartbeat = 700,
-    state = constants.nodeState.UP
+    state = constants.nodeState.DOWN
+  };
+  updateData[Ip_own] = {
+    revision = 1,
+    heartbeat = 800,
+    state = constants.nodeState.DOWN
   };
   network.updateNetworkState(updateData);
   -- send duplicate data

lua_modules/yeelink/yeelink_lib.lua

@@ -54,10 +54,10 @@ end)
 -- apikey must be -> string <-
 -- e.g. xxx.init(00000,00000,"123j12b3jkb12k4b23bv54i2b5b3o4")
 --========================================
-function M.init(_device, _sensor, _apikey)
-    device = tostring(_device)
-    sensor = tostring(_sensor)
-    apikey = _apikey
+function M.init(device_, sensor_, apikey_)
+    device = tostring(device_)
+    sensor = tostring(sensor_)
+    apikey = apikey_
     if dns == "0.0.0.0" then
       tmr.create():alarm(5000,tmr.ALARM_AUTO,function ()
         if dns == "0.0.0.0" then
@@ -90,9 +90,9 @@ end
 --
 --e.g. xxx.update(233.333)
 --============================================================
-function M.update(_datapoint)
+function M.update(datapoint_)
 
-    datapoint = tostring(_datapoint)
+    datapoint = tostring(datapoint_)
 
     sk:on("connection", function()