Be more judicious about responding to want_response in existing meshes (#9014)

* Be more judicious about sending want_response in existing meshes and responding to nodes we already heard from

* Turns out we don't actually use this

src/modules/NodeInfoModule.cpp

@@ -7,17 +7,41 @@
 #include "configuration.h"
 #include "main.h"
 #include <Throttle.h>
+#include <algorithm>
+
+#ifndef USERPREFS_NODEINFO_REPLY_SUPPRESS_SECS
+#define USERPREFS_NODEINFO_REPLY_SUPPRESS_SECS (12 * 60 * 60)
+#endif
 
 NodeInfoModule *nodeInfoModule;
 
+static constexpr uint32_t NodeInfoReplySuppressSeconds = USERPREFS_NODEINFO_REPLY_SUPPRESS_SECS;
+
 bool NodeInfoModule::handleReceivedProtobuf(const meshtastic_MeshPacket &mp, meshtastic_User *pptr)
 {
+    suppressReplyForCurrentRequest = false;
+
     if (mp.from == nodeDB->getNodeNum()) {
         LOG_WARN("Ignoring packet supposed to be from our own node: %08x", mp.from);
         return false;
     }
 
     auto p = *pptr;
+
+    if (mp.decoded.want_response) {
+        const NodeNum sender = getFrom(&mp);
+        const uint32_t now = mp.rx_time ? mp.rx_time : getTime();
+        auto it = lastNodeInfoSeen.find(sender);
+        if (it != lastNodeInfoSeen.end()) {
+            uint32_t sinceLast = now >= it->second ? now - it->second : 0;
+            if (sinceLast < NodeInfoReplySuppressSeconds) {
+                suppressReplyForCurrentRequest = true;
+            }
+        }
+        lastNodeInfoSeen[sender] = now;
+        pruneLastNodeInfoCache();
+    }
+
     if (p.is_licensed != owner.is_licensed) {
         LOG_WARN("Invalid nodeInfo detected, is_licensed mismatch!");
         return true;
@@ -42,6 +66,8 @@ bool NodeInfoModule::handleReceivedProtobuf(const meshtastic_MeshPacket &mp, mes
         service->sendToPhone(packetCopy);
     }
 
+    pruneLastNodeInfoCache();
+
     // LOG_DEBUG("did handleReceived");
     return false; // Let others look at this message also if they want
 }
@@ -68,9 +94,11 @@ void NodeInfoModule::sendOurNodeInfo(NodeNum dest, bool wantReplies, uint8_t cha
 
     if (p) { // Check whether we didn't ignore it
         p->to = dest;
-        p->decoded.want_response = (config.device.role != meshtastic_Config_DeviceConfig_Role_TRACKER &&
+        bool requestWantResponse = (config.device.role != meshtastic_Config_DeviceConfig_Role_TRACKER &&
                                     config.device.role != meshtastic_Config_DeviceConfig_Role_SENSOR) &&
                                    wantReplies;
+
+        p->decoded.want_response = requestWantResponse;
         if (_shorterTimeout)
             p->priority = meshtastic_MeshPacket_Priority_DEFAULT;
         else
@@ -89,6 +117,13 @@ void NodeInfoModule::sendOurNodeInfo(NodeNum dest, bool wantReplies, uint8_t cha
 
 meshtastic_MeshPacket *NodeInfoModule::allocReply()
 {
+    if (suppressReplyForCurrentRequest) {
+        LOG_DEBUG("Skip send NodeInfo since we heard the requester <12h ago");
+        ignoreRequest = true;
+        suppressReplyForCurrentRequest = false;
+        return NULL;
+    }
+
     if (!airTime->isTxAllowedChannelUtil(false)) {
         ignoreRequest = true; // Mark it as ignored for MeshModule
         LOG_DEBUG("Skip send NodeInfo > 40%% ch. util");
@@ -125,6 +160,29 @@ meshtastic_MeshPacket *NodeInfoModule::allocReply()
     }
 }
 
+void NodeInfoModule::pruneLastNodeInfoCache()
+{
+    if (!nodeDB || !nodeDB->meshNodes)
+        return;
+
+    const size_t maxEntries = nodeDB->meshNodes->size();
+
+    for (auto it = lastNodeInfoSeen.begin(); it != lastNodeInfoSeen.end();) {
+        if (!nodeDB->getMeshNode(it->first)) {
+            it = lastNodeInfoSeen.erase(it);
+        } else {
+            ++it;
+        }
+    }
+
+    while (!lastNodeInfoSeen.empty() && lastNodeInfoSeen.size() > maxEntries) {
+        auto oldestIt = std::min_element(lastNodeInfoSeen.begin(), lastNodeInfoSeen.end(),
+                                         [](const std::pair<const NodeNum, uint32_t> &lhs,
+                                            const std::pair<const NodeNum, uint32_t> &rhs) { return lhs.second < rhs.second; });
+        lastNodeInfoSeen.erase(oldestIt);
+    }
+}
+
 NodeInfoModule::NodeInfoModule()
     : ProtobufModule("nodeinfo", meshtastic_PortNum_NODEINFO_APP, &meshtastic_User_msg), concurrency::OSThread("NodeInfo")
 {

src/modules/NodeInfoModule.h

@@ -1,5 +1,6 @@
 #pragma once
 #include "ProtobufModule.h"
+#include <map>
 
 /**
  * NodeInfo module for sending/receiving NodeInfos into the mesh
@@ -43,6 +44,10 @@ class NodeInfoModule : public ProtobufModule<meshtastic_User>, private concurren
   private:
     uint32_t lastSentToMesh = 0; // Last time we sent our NodeInfo to the mesh
     bool shorterTimeout = false;
+    bool suppressReplyForCurrentRequest = false;
+    std::map<NodeNum, uint32_t> lastNodeInfoSeen;
+
+    void pruneLastNodeInfoCache();
 };
 
 extern NodeInfoModule *nodeInfoModule;

userPrefs.jsonc

@@ -55,6 +55,7 @@
   // "USERPREFS_MQTT_TLS_ENABLED": "false",
   // "USERPREFS_MQTT_ROOT_TOPIC": "event/REPLACEME",
   // "USERPREFS_RINGTONE_NAG_SECS": "60",
+  // "USERPREFS_NODEINFO_REPLY_SUPPRESS_SECS": "43200",
   "USERPREFS_RINGTONE_RTTTL": "24:d=32,o=5,b=565:f6,p,f6,4p,p,f6,p,f6,2p,p,b6,p,b6,p,b6,p,b6,p,b,p,b,p,b,p,b,p,b,p,b,p,b,p,b,1p.,2p.,p",
   // "USERPREFS_NETWORK_IPV6_ENABLED": "1",
   "USERPREFS_TZ_STRING": "tzplaceholder                                         "