Use time ms for timespan in redis

API/Controller/Admin/GetOnlineDevices.cs

@@ -73,7 +73,9 @@ public sealed class AdminOnlineDeviceResponse
         public required DateTimeOffset ConnectedAt { get; init; }
 
         public required string? UserAgent { get; init; }
+        [JsonConverter(typeof(TimeSpanToMillisecondsConverter))]
         public required TimeSpan? Uptime { get; init; }
+        [JsonConverter(typeof(TimeSpanToMillisecondsConverter))]
         public required TimeSpan? Latency { get; init; }
     }
 }

Common/JsonSerialization/TimeSpanToMillisecondsConverter.cs

@@ -0,0 +1,28 @@
+namespace OpenShock.Common.JsonSerialization;
+
+using System;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+public class TimeSpanToMillisecondsConverter : JsonConverter<TimeSpan>
+{
+    // Converts TimeSpan to JSON
+    public override void Write(Utf8JsonWriter writer, TimeSpan value, JsonSerializerOptions options)
+    {
+        // Convert TimeSpan to total milliseconds and write it as a JSON number
+        writer.WriteNumberValue(value.TotalMilliseconds);
+    }
+
+    // Converts JSON to TimeSpan
+    public override TimeSpan Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+    {
+        if (reader.TokenType != JsonTokenType.Number)
+        {
+            throw new JsonException("Expected number representing milliseconds.");
+        }
+
+        // Read the milliseconds as a double and convert to TimeSpan
+        var milliseconds = reader.GetDouble();
+        return TimeSpan.FromMilliseconds(milliseconds);
+    }
+}

Common/Redis/DeviceOnline.cs

@@ -15,6 +15,9 @@ public sealed class DeviceOnline
     public required string Gateway { get; set; }
     public required DateTimeOffset ConnectedAt { get; set; }
     public string? UserAgent { get; set; } = null;
+
+    [JsonConverter(typeof(TimeSpanToMillisecondsConverter))]
     public TimeSpan? Uptime { get; set; }
+    [JsonConverter(typeof(TimeSpanToMillisecondsConverter))]
     public TimeSpan? Latency { get; set; }
 }