Add wifi roaming #294 #270

ConfigSettings.cpp

@@ -522,11 +522,13 @@ bool WifiSettings::begin() {
 bool WifiSettings::fromJSON(JsonObject &obj) {
   this->parseValueString(obj, "ssid", this->ssid, sizeof(this->ssid));
   this->parseValueString(obj, "passphrase", this->passphrase, sizeof(this->passphrase));
+  if(obj.containsKey("roaming")) this->roaming = obj["roaming"];
   return true;
 }
 bool WifiSettings::toJSON(JsonObject &obj) {
   obj["ssid"] = this->ssid;
   obj["passphrase"] = this->passphrase;
+  obj["roaming"] = this->roaming;
   return true;
 }
 bool WifiSettings::save() {
@@ -534,6 +536,7 @@ bool WifiSettings::save() {
   pref.clear();
   pref.putString("ssid", this->ssid);
   pref.putString("passphrase", this->passphrase);
+  pref.putBool("roaming", this->roaming);
   pref.end();
   return true;
 }
@@ -543,6 +546,7 @@ bool WifiSettings::load() {
   pref.getString("passphrase", this->passphrase, sizeof(this->passphrase));
   this->ssid[sizeof(this->ssid) - 1] = '\0';
   this->passphrase[sizeof(this->passphrase) - 1] = '\0';
+  this->roaming = pref.getBool("roaming", true);
   pref.end();
   return true;
 }

ConfigSettings.h

@@ -59,6 +59,7 @@ class NTPSettings: BaseSettings {
 class WifiSettings: BaseSettings {
   public:
     WifiSettings();
+    bool roaming = true;
     char ssid[65] = "";
     char passphrase[65] = "";
     //bool ssdpBroadcast = true;

Network.cpp

@@ -16,6 +16,7 @@ extern MQTTClass mqtt;
 extern rebootDelay_t rebootDelay;
 extern Network net;
 
+static bool _apScanning = false;
 int connectRetries = 0;
 void Network::end() {
   sockEmit.end();
@@ -24,9 +25,11 @@ void Network::end() {
   delay(100);
 }
 bool Network::setup() {
+  WiFi.setScanMethod(WIFI_ALL_CHANNEL_SCAN);
+  WiFi.setSortMethod(WIFI_CONNECT_AP_BY_SIGNAL);
   WiFi.persistent(false);
   WiFi.onEvent(this->networkEvent);
-  if(WiFi.status() == WL_CONNECTED) WiFi.disconnect(true);
+  if(WiFi.status() == WL_CONNECTED) WiFi.disconnect(true, true);
   if(settings.connType == conn_types::wifi || settings.connType == conn_types::unset) {
     WiFi.persistent(false);
     if(settings.hostname[0] != '\0') WiFi.setHostname(settings.hostname);
@@ -63,8 +66,36 @@ void Network::loop() {
     // the MDNS library.  The original library required manual updates
     // to the MDNS or it would lose its hostname after 2 minutes.
     if(this->lastMDNS != 0) MDNS.setInstanceName(settings.hostname);
+    // Every 60 seconds we are going to look at wifi connectivity
+    // to get around the roaming issues with ESP32.  We will try to do this in an async manner.  If
+    // there is a channel that is better we will stop the radio and reconnect
+    if(this->connType == conn_types::wifi && settings.WIFI.roaming && !this->softAPOpened) {
+      // If we are not already scanning then we need to start a passive scan
+      // and only respond if there is a better connection. 
+      // 1. If there is currently a waiting scan don't do anything
+      if(!_apScanning && WiFi.scanNetworks(true, false, true, 300, 0, settings.WIFI.ssid) == -1) {
+        _apScanning = true;
+      }
+    }
     this->lastMDNS = millis();
   }
+  if(_apScanning) {
+    if(!settings.WIFI.roaming || this->connType != conn_types::wifi || this->softAPOpened) _apScanning = false;
+    else {
+      uint16_t n = WiFi.scanComplete();
+      if( n > 0) {
+        _apScanning = false;
+        uint8_t bssid[6];
+        int32_t channel = 0;
+        if(this->getStrongestAP(settings.WIFI.ssid, bssid, &channel)) {
+          if(memcmp(bssid, WiFi.BSSID(), sizeof(bssid)) != 0) {
+            Serial.printf("Found stronger AP %d %02X:%02X:%02X:%02X:%02X:%02X\n", channel, bssid[0], bssid[1], bssid[2], bssid[3], bssid[4], bssid[5]);
+            this->changeAP(bssid, channel);
+          }
+        }
+      }
+    }
+  }
   if(settings.ssdpBroadcast) {
     if(!SSDP.isStarted) SSDP.begin();
     if(SSDP.isStarted) SSDP.loop();
@@ -72,6 +103,47 @@ void Network::loop() {
   else if(!settings.ssdpBroadcast && SSDP.isStarted) SSDP.end();
   mqtt.loop();
 }
+bool Network::changeAP(const uint8_t *bssid, const int32_t channel) {
+  if(SSDP.isStarted) SSDP.end();
+  mqtt.disconnect();
+  WiFi.disconnect(false, true);
+  WiFi.begin(settings.WIFI.ssid, settings.WIFI.passphrase, channel, bssid);
+  uint8_t retries = 0;
+  while(retries < 100) {
+    wl_status_t stat = WiFi.status();
+    if(stat == WL_CONNECTED) {
+      Serial.println("WiFi module connected");
+      this->ssid = WiFi.SSID();
+      this->mac = WiFi.BSSIDstr();
+      this->strength = WiFi.RSSI();
+      this->channel = WiFi.channel();
+      return true;
+    }
+    else if(stat == WL_CONNECT_FAILED) {
+      Serial.println("WiFi Module connection failed");
+      return false;
+    }
+    else if(stat == WL_NO_SSID_AVAIL) {
+        Serial.println(" Connection failed the SSID ");
+        return false;
+    }
+    else if(stat == WL_NO_SHIELD) {
+        Serial.println("Connection failed - WiFi module not found");
+        return false;
+    }
+    else if(stat == WL_IDLE_STATUS) {
+        Serial.print("*");
+    }
+    else if(stat == WL_DISCONNECTED) {
+        Serial.print("-");
+    }
+    else {
+      Serial.printf("Unknown status %d\n", stat);
+    }
+    delay(300);
+  }
+  return false;
+}
 void Network::emitSockets() {
   if(this->needsBroadcast || 
     (this->connType == conn_types::wifi && (abs(abs(WiFi.RSSI()) - abs(this->lastRSSI)) > 1 || WiFi.channel() != this->lastChannel))) {
@@ -91,7 +163,7 @@ void Network::emitSockets(uint8_t num) {
   }
   else {
       if(WiFi.status() == WL_CONNECTED) {
-        snprintf(buf, sizeof(buf), "{\"ssid\":\"%s\",\"strength\":%d,\"channel\":%d}", WiFi.SSID().c_str(), WiFi.RSSI(), WiFi.channel());
+        snprintf(buf, sizeof(buf), "{\"ssid\":\"%s\",\"strength\":%d,\"channel\":%d}", WiFi.SSID().c_str(), WiFi.RSSI(), this->channel);
         if(num == 255)
           sockEmit.sendToClients("wifiStrength", buf);
         else
@@ -122,6 +194,10 @@ void Network::setConnected(conn_types connType) {
       WiFi.softAPdisconnect(true);
       WiFi.mode(WIFI_STA);
     }
+    this->ssid = WiFi.SSID();
+    this->mac = WiFi.BSSIDstr();
+    this->strength = WiFi.RSSI();
+    this->channel = WiFi.channel();
   }
   else if(this->connType == conn_types::ethernet) {
     if(this->softAPOpened) {
@@ -356,7 +432,14 @@ bool Network::connectWiFi() {
     WiFi.mode(WIFI_STA);
     WiFi.setScanMethod(WIFI_ALL_CHANNEL_SCAN);
     WiFi.setSortMethod(WIFI_CONNECT_AP_BY_SIGNAL);
-    WiFi.begin(settings.WIFI.ssid, settings.WIFI.passphrase);
+    uint8_t bssid[6];
+    int32_t channel = 0;
+    if(this->getStrongestAP(settings.WIFI.ssid, bssid, &channel)) {
+      Serial.printf("Found strongest AP %d %02X:%02X:%02X:%02X:%02X:%02X\n", channel, bssid[0], bssid[1], bssid[2], bssid[3], bssid[4], bssid[5]);
+      WiFi.begin(settings.WIFI.ssid, settings.WIFI.passphrase, channel, bssid);
+    }
+    else
+      WiFi.begin(settings.WIFI.ssid, settings.WIFI.passphrase);
     delay(100);
     int retries = 0;
     while(retries < 100) {
@@ -439,6 +522,25 @@ uint32_t Network::getChipId() {
   }
   return chipId;
 }
+
+bool Network::getStrongestAP(const char *ssid, uint8_t *bssid, int32_t *channel) {
+  // The new AP must be at least 10dbm greater.
+  int32_t strength = this->connected() ? WiFi.RSSI() + 10 : -127;
+  int32_t chan = -1;
+  memset(bssid, 0x00, 6);
+  uint8_t n = this->connected() ? WiFi.scanComplete() : WiFi.scanNetworks(false, false, false, 300, 0, ssid);
+  for(uint8_t i = 0; i < n; i++) {
+    if(WiFi.SSID(i).compareTo(ssid) == 0) {
+      if(WiFi.RSSI(i) > strength) { 
+        strength = WiFi.RSSI(i); 
+        memcpy(bssid, WiFi.BSSID(i), 6); 
+        *channel = chan = WiFi.channel(i);
+      }
+    }
+  }  
+  WiFi.scanDelete();
+  return chan > 0;
+}
 int Network::getStrengthBySSID(const char *ssid) {
   int32_t strength = -100;
   int n = WiFi.scanNetworks(false, false);

Network.h

@@ -29,6 +29,8 @@ class Network {
     bool connectWiFi();
     bool connectWired();
     void setConnected(conn_types connType);
+    bool getStrongestAP(const char *ssid, uint8_t *bssid, int32_t *channel);
+    bool changeAP(const uint8_t *bssid, const int32_t channel);
     //int getStrengthByMac(const char *mac);
     int getStrengthBySSID(const char *ssid);
     void updateHostname();

data/index.html

@@ -3,11 +3,11 @@
 <head>
     <meta name="viewport" content="width=device-width, initial-scale=1">
     <meta charset="UTF-8">
-    <link rel="stylesheet" href="main.css?v=2.4.1a" type="text/css" />
+    <link rel="stylesheet" href="main.css?v=2.4.1b" type="text/css" />
-    <link rel="stylesheet" href="widgets.css?v=2.4.1a" type="text/css" />
+    <link rel="stylesheet" href="widgets.css?v=2.4.1b" type="text/css" />
-    <link rel="stylesheet" href="icons.css?v=2.4.1a" type="text/css" />
+    <link rel="stylesheet" href="icons.css?v=2.4.1b" type="text/css" />
     <link rel="icon" type="image/png" href="favicon.png" />
-    <script type="text/javascript" src="index.js?v=2.4.1a"></script>
+    <script type="text/javascript" src="index.js?v=2.4.1b"></script>
 </head>
 <body>
     <div id="divContainer" class="container main" data-auth="false">
@@ -157,6 +157,10 @@
                         <div class="field-group" style="vertical-align:middle;color:#00bcd4;margin-top:-24px;margin-bottom:18px;">
                             <input id="cbHardwired" name="hardwired" data-bind="ethernet.hardwired" type="checkbox" style="display:inline-block;" onclick="wifi.useEthernetClicked();" />
                             <label for="cbHardwired" style="display:inline-block;cursor:pointer;">Use Ethernet</label>
+                            <div id="divRoaming" style="display:inline-block;padding-left:7px;">
+                                <input id="cbRoaming" name="roaming" data-bind="wifi.roaming" type="checkbox" style="display:inline-block;" />
+                                <label for="cbRoaming" style="display:inline-block;cursor:pointer;">Enable Roaming</label>
+                            </div>
                             <div id="divFallbackWireless" style="display:inline-block;padding-left:7px;">
                                 <input id="cbFallbackWireless" name="fallbackwireless" data-bind="ethernet.wirelessFallback" type="checkbox" style="display:inline-block;" />
                                 <label for="cbFallbackWireless" style="display:inline-block;cursor:pointer;">Fallback to Wireless</label>

data/index.js

@@ -1672,12 +1672,14 @@ class Wifi {
                 if (settings.connType >= 2) {
                     document.getElementById('divWiFiMode').style.display = 'none';
                     document.getElementById('divEthernetMode').style.display = '';
+                    document.getElementById('divRoaming').style.display = 'none';
                     document.getElementById('divFallbackWireless').style.display = 'inline-block';
                 }
                 else {
                     document.getElementById('divWiFiMode').style.display = '';
                     document.getElementById('divEthernetMode').style.display = 'none';
                     document.getElementById('divFallbackWireless').style.display = 'none';
+                    document.getElementById('divRoaming').style.display = 'inline-block';
                 }
                 document.getElementById('divETHSettings').style.display = settings.ethernet.boardType === 0 ? '' : 'none';
                 document.getElementById('divStaticIP').style.display = settings.ip.dhcp ? 'none' : '';
@@ -1691,6 +1693,7 @@ class Wifi {
         document.getElementById('divWiFiMode').style.display = useEthernet ? 'none' : '';
         document.getElementById('divEthernetMode').style.display = useEthernet ? '' : 'none';
         document.getElementById('divFallbackWireless').style.display = useEthernet ? 'inline-block' : 'none';
+        document.getElementById('divRoaming').style.display = useEthernet ? 'none' : 'inline-block';
     }
     async loadAPs() {
         if (document.getElementById('btnScanAPs').classList.contains('disabled')) return;
@@ -1878,6 +1881,7 @@ class Wifi {
     }
     procWifiStrength(strength) {
         let ssid = strength.ssid || strength.name;
+        console.log(strength);
         document.getElementById('spanNetworkSSID').innerHTML = !ssid || ssid === '' ? '-------------' : ssid;
         document.getElementById('spanNetworkChannel').innerHTML = isNaN(strength.channel) || strength.channel < 0 ? '--' : strength.channel;
         let cssClass = 'waveStrength-' + (isNaN(strength.strength) || strength > 0 ? -100 : this.calcWaveStrength(strength.strength));