From 47342abc998432e6e0b4dd74e4c86d3e09eeaaff Mon Sep 17 00:00:00 2001
From: n30nex <blushellneon@outlook.com>
Date: Sat, 26 Sep 2026 22:34:58 -0400
Subject: [PATCH] fix(observers): keep non-finite signal samples out of JSON

---
 db/observer_metrics_integration_test.go |  6 +++++-
 db/observers.go                         | 15 +++++++++++++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/db/observer_metrics_integration_test.go b/db/observer_metrics_integration_test.go
index 868ce6c..f4e114e 100644
--- a/db/observer_metrics_integration_test.go
+++ b/db/observer_metrics_integration_test.go
@@ -3,6 +3,7 @@
 package db
 
 import (
+	"encoding/json"
 	sqlc "github.com/MeshCore-Beacon/beacon-server/db/sqlc"
 	"github.com/google/uuid"
 	"github.com/jackc/pgx/v5/pgtype"
@@ -30,7 +31,7 @@ func TestObserverMetricsPostgres(t *testing.T) {
  INSERT INTO observers (id,public_key) VALUES ('00000000-0000-0000-0000-000000000001','\x01');
  INSERT INTO packets(packet_hash,payload_type,last_heard_at,first_heard_at) SELECT int4send(i),4,NOW()-interval '5 days',NOW()-interval '5 days' FROM generate_series(1,3) i;
  INSERT INTO packet_observations(packet_hash,observer_id,iata,heard_at,path_length_byte,hash_size,hop_count,payload_type,snr,rssi)
- SELECT packet_hash,'00000000-0000-0000-0000-000000000001','YOW',date_trunc('hour',NOW())-interval '5 days',0,1,0,CASE WHEN packet_hash=int4send(1) THEN 4 END,0,-100 FROM packets;
+ SELECT packet_hash,'00000000-0000-0000-0000-000000000001','YOW',date_trunc('hour',NOW())-interval '5 days',0,1,0,CASE WHEN packet_hash=int4send(1) THEN 4 END,CASE WHEN packet_hash=int4send(2) THEN 'NaN'::real ELSE 0 END,-100 FROM packets;
  `); err != nil {
 		t.Fatal(err)
 	}
@@ -48,6 +49,9 @@ func TestObserverMetricsPostgres(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	if _, err := json.Marshal(activity); err != nil {
+		t.Fatalf("non-finite sample leaked into JSON: %v", err)
+	}
 	if activity.Summary.RecordedPackets != 3 || len(activity.PayloadTypes) != 2 || activity.Summary.LatestRecordedAt != nil || activity.Summary.LastCompleteHour != 0 {
 		t.Fatalf("archive summary: %+v types=%+v", activity.Summary, activity.PayloadTypes)
 	}
diff --git a/db/observers.go b/db/observers.go
index 1735042..09a377a 100644
--- a/db/observers.go
+++ b/db/observers.go
@@ -8,6 +8,7 @@ import (
 	"encoding/hex"
 	"fmt"
 	"log/slog"
+	"math"
 	"time"
 
 	sqlc "github.com/MeshCore-Beacon/beacon-server/db/sqlc"
@@ -296,7 +297,12 @@ func (s *Store) GetObserverActivity(ctx context.Context, observerID uuid.UUID, w
 			if r.SnrN > 0 {
 				avg := r.SnrSum / float32(r.SnrN)
 				min := r.SnrMin
-				p.SNRAvg, p.SNRMin = &avg, &min
+				if !math.IsNaN(float64(avg)) && !math.IsInf(float64(avg), 0) {
+					p.SNRAvg = &avg
+				}
+				if !math.IsNaN(float64(min)) && !math.IsInf(float64(min), 0) {
+					p.SNRMin = &min
+				}
 			}
 			if r.RssiN > 0 {
 				avg := float32(r.RssiSum) / float32(r.RssiN)
@@ -346,7 +352,12 @@ func (s *Store) GetObserverActivity(ctx context.Context, observerID uuid.UUID, w
 		}
 		if r.SnrN > 0 {
 			avg, min := r.SnrAvg, r.SnrMin
-			p.SNRAvg, p.SNRMin = &avg, &min
+			if !math.IsNaN(float64(avg)) && !math.IsInf(float64(avg), 0) {
+				p.SNRAvg = &avg
+			}
+			if !math.IsNaN(float64(min)) && !math.IsInf(float64(min), 0) {
+				p.SNRMin = &min
+			}
 		}
 		if r.RssiN > 0 {
 			avg := r.RssiAvg