Feat 0.15.0 sort relays

lib/api/get-relays-meta.dart

@@ -0,0 +1,185 @@
+import 'dart:convert';
+
+import 'package:collection/collection.dart';
+import 'package:flutter_animate/flutter_animate.dart';
+import 'package:locus/utils/access-deeply-nested-key.dart';
+import 'package:locus/utils/nostr_fetcher/BasicNostrFetchSocket.dart';
+import 'package:locus/utils/nostr_fetcher/NostrSocket.dart';
+import 'package:nostr/nostr.dart';
+
+const MIN_LENGTH = 5000;
+
+class RelaysMetaFetcher extends BasicNostrFetchSocket {
+  List<RelayMeta> meta = [];
+
+  RelaysMetaFetcher({
+    required super.relay,
+    super.timeout,
+  });
+
+  @override
+  void onEndOfStream() {
+    closeConnection();
+  }
+
+  @override
+  void onNostrEvent(final Message message) {
+    // Relay URL, canWrite and canRead are in message.tags
+    // Latencies are saved in content, separated per region
+    // with the following schema:
+    //  [
+    //    [<connection speed>],
+    //    [<read speed>],
+    //    [<write speed>],
+    //  ]
+    final event = message.message as Event;
+
+    final relayMeta = RelayMeta.fromFetchedContent(
+      canWrite: event.tags[1][1] == "true",
+      canRead: event.tags[2][1] == "true",
+      relay: event.tags[0][1],
+      content: jsonDecode(event.content),
+      worldRegion: "eu-west",
+    );
+
+    meta.add(relayMeta);
+  }
+
+  @override
+  void onError(error) {
+    closeConnection();
+  }
+}
+
+class RelayMeta {
+  final String relay;
+  final bool canWrite;
+  final bool canRead;
+  final String contactInfo;
+  final String description;
+  final String name;
+
+  final List<int> connectionLatencies;
+  final List<int> readLatencies;
+  final List<int> writeLatencies;
+
+  final int maxMessageLength;
+  final int maxContentLength;
+
+  final int minPowDifficulty;
+  final bool requiresPayment;
+
+  const RelayMeta({
+    required this.relay,
+    required this.canWrite,
+    required this.canRead,
+    required this.contactInfo,
+    required this.description,
+    required this.name,
+    required this.connectionLatencies,
+    required this.readLatencies,
+    required this.writeLatencies,
+    required this.maxMessageLength,
+    required this.maxContentLength,
+    required this.minPowDifficulty,
+    required this.requiresPayment,
+  });
+
+  factory RelayMeta.fromFetchedContent({
+    required final Map<String, dynamic> content,
+    required final String relay,
+    required final bool canRead,
+    required final bool canWrite,
+    required final String worldRegion,
+  }) =>
+      RelayMeta(
+          relay: relay,
+          canRead: canRead,
+          canWrite: canWrite,
+          name: adnk<dynamic>(content, "info.name") ?? relay,
+          contactInfo: adnk<dynamic>(content, "info.contact") ?? "",
+          description: adnk<dynamic>(content, "info.description") ?? "",
+          connectionLatencies: List<int?>.from(
+                  adnk<dynamic>(content, "latency.$worldRegion.0") ?? [])
+              .where((value) => value != null)
+              .toList()
+              .cast<int>(),
+          readLatencies:
+              List<int?>.from(adnk<dynamic>(content, "latency.$worldRegion.1") ?? [])
+                  .where((value) => value != null)
+                  .toList()
+                  .cast<int>(),
+          writeLatencies:
+              List<int?>.from(adnk<dynamic>(content, "latency.$worldRegion.2") ?? [])
+                  .where((value) => value != null)
+                  .toList()
+                  .cast<int>(),
+          maxContentLength:
+              adnk<dynamic>(content, "info.limitations.max_content_length") ??
+                  MIN_LENGTH,
+          maxMessageLength:
+              adnk<dynamic>(content, "info.limitations.max_message_length") ??
+                  MIN_LENGTH,
+          requiresPayment:
+              adnk<dynamic>(content, "info.limitations.payment_required") ??
+                  false,
+          minPowDifficulty:
+              adnk<dynamic>(content, "info.limitations.min_pow_difficulty") ??
+                  0);
+
+  bool get isSuitable =>
+      canWrite &&
+      canRead &&
+      !requiresPayment &&
+      minPowDifficulty == 0 &&
+      maxContentLength >= MIN_LENGTH;
+
+  // Calculate average latency, we use the average as we want extreme highs
+  // to be taken into account.
+  double get score {
+    if (connectionLatencies.isEmpty ||
+        readLatencies.isEmpty ||
+        writeLatencies.isEmpty) {
+      // If there is no data available, we don't know if the relay is fully intact
+      return double.infinity;
+    }
+
+    // Each latency has it's own factor to give each of them a different weight
+    // Lower latency = better - Because of this
+    // a factor closer to 0 resembles a HIGHER weight
+    // We prioritize read latency as we want to be able to provide a fast app
+    // Lower score = better
+    return (connectionLatencies.average * 0.9 +
+            readLatencies.average * 0.5 +
+            writeLatencies.average) +
+        (maxContentLength - MIN_LENGTH) * 0.0001;
+  }
+}
+
+// Values taken from https://github.com/dskvr/nostr-watch/blob/develop/src/components/relays/jobs/LoadSeed.vue#L91
+final REQUEST_DATA = NostrSocket.createNostrRequestData(
+  kinds: [30304],
+  limit: 1000,
+  from: DateTime.now().subtract(2.hours),
+  authors: ["b3b0d247f66bf40c4c9f4ce721abfe1fd3b7529fbc1ea5e64d5f0f8df3a4b6e6"],
+);
+
+Future<Map<String, List<RelayMeta>>> fetchRelaysMeta() async {
+  final fetcher = RelaysMetaFetcher(
+    relay: "wss://history.nostr.watch",
+  );
+  await fetcher.connect();
+  fetcher.addData(
+    Request(
+      generate64RandomHexChars(),
+      [
+        REQUEST_DATA,
+      ],
+    ).serialize(),
+  );
+  await fetcher.onComplete;
+
+  return {
+    "meta": fetcher.meta,
+  };
+}

lib/l10n/app_en.arb

@@ -110,6 +110,8 @@
     }
   },
   "relaySelectSheet_selectRandomRelays": "Select {count} random Nostr Relays",
+  "relaySelectSheet_loadingRelaysMeta": "Loading Nostr Relays information...",
+  "relaySelectSheet_hint": "Relays are sorted from best to worst in ascending order. The best relays are at the top.",
   "taskAction_start": "Start Task",
   "taskAction_started_title": "Task started",
   "taskAction_started_description": "Task started at {date}",

lib/main.dart

@@ -7,6 +7,7 @@ import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:flutter_logs/flutter_logs.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 import 'package:locus/App.dart';
+import 'package:locus/api/get-relays-meta.dart';
 import 'package:locus/screens/locations_overview_screen_widgets/LocationFetchers.dart';
 import 'package:locus/services/app_update_service.dart';
 import 'package:locus/services/current_location_service.dart';

lib/screens/LocationsOverviewScreen.dart

@@ -19,6 +19,7 @@ import 'package:flutter_map_marker_popup/flutter_map_marker_popup.dart';
 import 'package:flutter_platform_widgets/flutter_platform_widgets.dart';
 import 'package:geolocator/geolocator.dart';
 import 'package:latlong2/latlong.dart';
+import 'package:locus/api/get-relays-meta.dart';
 import 'package:locus/constants/spacing.dart';
 import 'package:locus/screens/ImportTaskSheet.dart';
 import 'package:locus/screens/SettingsScreen.dart';

lib/screens/locations_overview_screen_widgets/ActiveSharesSheet.dart

@@ -460,7 +460,7 @@ class _ActiveSharesSheetState extends State<ActiveSharesSheet>
             child: SizedBox.square(),
           ),
         Expanded(
-          flex: 8,
+          flex: 6,
           child: Center(
             child: Text(
               l10n.locationsOverview_activeShares_amount(

lib/utils/access-deeply-nested-key.dart

@@ -0,0 +1,19 @@
+T? accessDeeplyNestedKey<T>(final Map<String, dynamic> obj, final String path) {
+  dynamic result = obj;
+
+  for (final subPath in path.split(".")) {
+    if (result is List) {
+      final index = int.tryParse(subPath)!;
+
+      result = result[index];
+    } else if (result.containsKey(subPath)) {
+      result = result[subPath];
+    } else {
+      return null;
+    }
+  }
+
+  return result as T;
+}
+
+const adnk = accessDeeplyNestedKey;

lib/utils/nostr_fetcher/NostrSocket.dart

@@ -3,7 +3,6 @@ import 'dart:async';
 import 'package:flutter_logs/flutter_logs.dart';
 import 'package:locus/constants/values.dart';
 import 'package:locus/services/location_point_service.dart';
-import 'package:locus/services/task_service/index.dart';
 import 'package:locus/services/task_service/mixins.dart';
 import 'package:locus/utils/nostr_fetcher/BasicNostrFetchSocket.dart';
 import 'package:locus/utils/nostr_fetcher/Socket.dart';
@@ -121,10 +120,12 @@ class NostrSocket extends BasicNostrFetchSocket {
     final int? limit,
     final DateTime? from,
     final DateTime? until,
+    final List<String>? authors,
   }) =>
       Filter(
         kinds: kinds,
         limit: limit,
+        authors: authors ?? [],
         since:
             from == null ? null : (from.millisecondsSinceEpoch / 1000).floor(),
         until: until == null

lib/utils/nostr_fetcher/Socket.dart

@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:convert';
 import 'dart:io';
 
 import 'package:flutter_logs/flutter_logs.dart';