NIP-65 relay list models and definitions

This commit adds the base models needed for the NIP-65 relay list support.

This introduces no user-facing changes.

Changelog-None
Signed-off-by: Daniel D’Aquino <daniel@daquino.me>

damus.xcodeproj/project.pbxproj

@@ -1649,6 +1649,9 @@
 		D7DB93052D66A44100DA1EE5 /* Undistractor.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7DB93042D66A43B00DA1EE5 /* Undistractor.swift */; };
 		D7DB93062D66A44100DA1EE5 /* Undistractor.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7DB93042D66A43B00DA1EE5 /* Undistractor.swift */; };
 		D7DB93072D66A44100DA1EE5 /* Undistractor.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7DB93042D66A43B00DA1EE5 /* Undistractor.swift */; };
+		D7DB930A2D69486700DA1EE5 /* NIP65.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7DB93092D69485A00DA1EE5 /* NIP65.swift */; };
+		D7DB930B2D69486700DA1EE5 /* NIP65.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7DB93092D69485A00DA1EE5 /* NIP65.swift */; };
+		D7DB930C2D69486700DA1EE5 /* NIP65.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7DB93092D69485A00DA1EE5 /* NIP65.swift */; };
 		D7DBD41F2B02F15E002A6197 /* NostrKind.swift in Sources */ = {isa = PBXBuildFile; fileRef = 4C3BEFD32819DE8F00B3DE84 /* NostrKind.swift */; };
 		D7DEEF2F2A8C021E00E0C99F /* NostrEventTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7DEEF2E2A8C021E00E0C99F /* NostrEventTests.swift */; };
 		D7EB00B02CD59C8D00660C07 /* PresentFullScreenItemNotify.swift in Sources */ = {isa = PBXBuildFile; fileRef = D7EB00AF2CD59C8300660C07 /* PresentFullScreenItemNotify.swift */; };
@@ -2537,6 +2540,7 @@
 		D7DB1FF02D5AC5D700CF06DA /* nip44.vectors.json */ = {isa = PBXFileReference; lastKnownFileType = text.json; path = nip44.vectors.json; sourceTree = "<group>"; };
 		D7DB1FF22D5AC5E400CF06DA /* LICENSES */ = {isa = PBXFileReference; lastKnownFileType = text; path = LICENSES; sourceTree = "<group>"; };
 		D7DB93042D66A43B00DA1EE5 /* Undistractor.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Undistractor.swift; sourceTree = "<group>"; };
+		D7DB93092D69485A00DA1EE5 /* NIP65.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NIP65.swift; sourceTree = "<group>"; };
 		D7DEEF2E2A8C021E00E0C99F /* NostrEventTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NostrEventTests.swift; sourceTree = "<group>"; };
 		D7EB00AF2CD59C8300660C07 /* PresentFullScreenItemNotify.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PresentFullScreenItemNotify.swift; sourceTree = "<group>"; };
 		D7EDED1B2B1178FE0018B19C /* NoteContent.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NoteContent.swift; sourceTree = "<group>"; };
@@ -3646,6 +3650,7 @@
 		4CE6DEE527F7A08100C66700 /* damus */ = {
 			isa = PBXGroup;
 			children = (
+				D7DB93082D69478400DA1EE5 /* NIP65 */,
 				D7DB1FDC2D5A77E500CF06DA /* NIP44 */,
 				D755B28B2D3E7D6500BBEEFA /* NIP37 */,
 				D78F08152D7F7F5F00FC6C75 /* NIP04 */,
@@ -4044,6 +4049,14 @@
 			path = NIP44;
 			sourceTree = "<group>";
 		};
+		D7DB93082D69478400DA1EE5 /* NIP65 */ = {
+			isa = PBXGroup;
+			children = (
+				D7DB93092D69485A00DA1EE5 /* NIP65.swift */,
+			);
+			path = NIP65;
+			sourceTree = "<group>";
+		};
 		E06336A72B7582D600A88E6B /* Assets */ = {
 			isa = PBXGroup;
 			children = (
@@ -4480,6 +4493,7 @@
 				F757933A29D7AECD007DEAC1 /* MediaPicker.swift in Sources */,
 				4CF0ABEE29844B5500D66079 /* AnyEncodable.swift in Sources */,
 				B57B4C662B312C3700A232C0 /* NostrAuth.swift in Sources */,
+				D7DB930B2D69486700DA1EE5 /* NIP65.swift in Sources */,
 				4CB8838D296F710400DC99E7 /* Reposted.swift in Sources */,
 				4C3EA67728FF7A9800C48A62 /* talstr.c in Sources */,
 				4CE6DEE927F7A08100C66700 /* ContentView.swift in Sources */,
@@ -5311,6 +5325,7 @@
 				82D6FBE02CD99F7900C925F4 /* ReactionsSettingsView.swift in Sources */,
 				82D6FBE12CD99F7900C925F4 /* NotificationSettingsView.swift in Sources */,
 				82D6FBE22CD99F7900C925F4 /* AppearanceSettingsView.swift in Sources */,
+				D7DB930A2D69486700DA1EE5 /* NIP65.swift in Sources */,
 				82D6FBE32CD99F7900C925F4 /* KeySettingsView.swift in Sources */,
 				82D6FBE42CD99F7900C925F4 /* ZapSettingsView.swift in Sources */,
 				82D6FBE52CD99F7900C925F4 /* TranslationSettingsView.swift in Sources */,
@@ -5715,6 +5730,7 @@
 				D73E5F012C6A97F4007EB227 /* ZapTypePicker.swift in Sources */,
 				D73E5F022C6A97F4007EB227 /* ZapUserView.swift in Sources */,
 				D73E5F032C6A97F4007EB227 /* ProfileZapLinkView.swift in Sources */,
+				D7DB930C2D69486700DA1EE5 /* NIP65.swift in Sources */,
 				D73E5F042C6A97F4007EB227 /* AboutView.swift in Sources */,
 				D73E5F052C6A97F4007EB227 /* ProfileName.swift in Sources */,
 				D73E5F062C6A97F4007EB227 /* ProfilePictureSelector.swift in Sources */,

damus/Models/HomeModel.swift

@@ -225,6 +225,8 @@ class HomeModel: ContactsDelegate {
             // TODO: Implement draft syncing with relays. We intentionally do not support that as of writing. See `DraftsModel.swift` for other details
             // try? damus_state.drafts.load(wrapped_draft_note: ev, with: damus_state)
             break
+        case .relay_list:
+            break   // This will be handled by `UserRelayListManager`
         }
     }
 

damus/Models/UserSettingsStore.swift

@@ -336,6 +336,10 @@ class UserSettingsStore: ObservableObject {
     @Setting(key: "draft_event_ids", default_value: nil)
     var draft_event_ids: [String]?
     
+    // TODO: Get rid of this once we have NostrDB query capabilities integrated
+    @Setting(key: "latest_relay_list_event_id", default_value: nil)
+    var latestRelayListEventIdHex: String?
+    
     // MARK: Helper types
     
     enum NotificationsMode: String, CaseIterable, Identifiable, StringCodable, Equatable {

damus/NIP65/NIP65.swift

@@ -0,0 +1,167 @@
+//
+//  NIP65.swift
+//  damus
+//
+//  Created by Daniel D’Aquino on 2025-02-21.
+//
+//  Some text excerpts taken from the Nostr Protocol itself (which are public domain)
+
+import OrderedCollections
+import Foundation
+
+/// Includes models and functions for working with NIP-65
+struct NIP65: Sendable {}
+
+extension NIP65 {
+    /// Models a NIP-65 relay list
+    struct RelayList: NostrEventConvertible, Sendable {
+        let relays: OrderedDictionary<RelayURL, RelayItem>
+
+        // MARK: - Initialization
+
+        init(event: NdbNote) throws(NIP65DecodingError) {
+            guard event.known_kind == .relay_list else { throw .notRelayList }
+            var relays: [RelayItem] = []
+            for tag in event.tags {
+                guard let relay = try RelayItem.fromTag(tag: tag) else { continue }
+                relays.append(relay)
+            }
+            self.relays = Self.relayOrderedDictionary(from: relays)
+        }
+        
+        init?(event: NdbNote?) throws(NIP65DecodingError) {
+            guard let event else { return nil }
+            try self.init(event: event)
+        }
+        
+        init(relays: [RelayItem]) {
+            self.relays = Self.relayOrderedDictionary(from: relays)
+        }
+        
+        init(relays: [RelayURL]) {
+            let relayItemList = relays.map({ RelayItem(url: $0, rwConfiguration: .readWrite) })
+            self.relays = Self.relayOrderedDictionary(from: relayItemList)
+        }
+        
+        private static func relayOrderedDictionary(from relayList: [RelayItem]) -> OrderedDictionary<RelayURL, RelayItem> {
+            var seenUrls: Set<RelayURL> = []
+            return OrderedDictionary(uniqueKeysWithValues: relayList.compactMap({
+                // We need to ensure the keys are unique to avoid assertion errors from OrderedDictionary
+                guard !seenUrls.contains($0.url) else { return nil }
+                seenUrls.insert($0.url)
+                return ($0.url, $0)
+            }))
+        }
+        
+        
+        // MARK: - Conversion to a Nostr Event
+        
+        func toNostrEvent(keypair: FullKeypair, timestamp: UInt32? = nil) -> NostrEvent? {
+            return NdbNote(
+                content: "",
+                keypair: keypair.to_keypair(),
+                kind: NostrKind.relay_list.rawValue,
+                tags: self.relays.values.map({ $0.tag }),
+                createdAt: timestamp ?? UInt32(Date.now.timeIntervalSince1970)
+            )
+        }
+    }
+}
+
+extension NIP65 {
+    /// An error thrown when decoding an item into a NIP-65 relay list
+    enum NIP65DecodingError: Error {
+        /// The Nostr event being converted is not a NIP-65 relay list
+        case notRelayList
+        /// The relay URL is invalid
+        case invalidRelayURL
+        ///The relay RW marker is invalid
+        case invalidRelayMarker
+    }
+}
+
+extension NIP65.RelayList {
+    /// An item referencing a relay and its configuration inside a relay list
+    struct RelayItem: ThrowingTagConvertible, Sendable {
+        typealias E = NIP65.NIP65DecodingError
+        
+        let url: RelayURL
+        let rwConfiguration: RWConfiguration
+
+        /// The raw tag sequence in a Nostr event
+        var tag: [String] {
+            var tag = ["r", url.absoluteString]
+            if let rwMarker = rwConfiguration.tagItem { tag.append(rwMarker) }
+            return tag
+        }
+
+        /// Initialize a new relay item from a Nostr event's tag sequence
+        static func fromTag(tag: TagSequence) throws(E) -> NIP65.RelayList.RelayItem? {
+            var i = tag.makeIterator()
+
+            guard tag.count >= 2,
+                  let t0 = i.next(),
+                  let key = t0.single_char,
+                  let rkey = RefId.RefKey(rawValue: key),
+                  let t1 = i.next()
+            else { return nil }
+            
+            let t2 = i.next()
+
+            switch rkey {
+            case .r: return try self.fromRawInfo(urlString: t1.string(), rwMarker: t2?.string())
+            // Keep options explicit to make compiler prompt developer on whether to ignore or handle new future options
+            case .e, .p, .q, .t, .d, .a: return nil
+            }
+        }
+
+        /// Initializes a Relay Item based on raw information
+        static func fromRawInfo(urlString: String, rwMarker: String?) throws(NIP65.NIP65DecodingError) -> NIP65.RelayList.RelayItem? {
+            guard let relayUrl = RelayURL(urlString) else { throw .invalidRelayURL }
+            guard let rwConfiguration = RWConfiguration.fromTagItem(rwMarker) else { throw .invalidRelayMarker }
+            return NIP65.RelayList.RelayItem(url: relayUrl, rwConfiguration: rwConfiguration)
+        }
+    }
+}
+
+extension NIP65.RelayList.RelayItem {
+    /// The read/write configuration for a relay item
+    enum RWConfiguration: TagItemConvertible {
+        case read
+        case write
+        case readWrite
+        
+        static let READ_MARKER: String = "read"
+        static let WRITE_MARKER: String = "write"
+        
+        var canRead: Bool {
+            switch self {
+            case .read, .readWrite: return true
+            case .write: return false
+            }
+        }
+        
+        var canWrite: Bool {
+            switch self {
+            case .write, .readWrite: return true
+            case .read: return false
+            }
+        }
+        
+        /// A raw Nostr Event tag item
+        var tagItem: String? {
+            switch self {
+            case .read: Self.READ_MARKER
+            case .write: Self.WRITE_MARKER
+            case .readWrite: nil
+            }
+        }
+        
+        /// Initialize this from a raw Nostr Event tag item
+        static func fromTagItem(_ item: String?) -> Self? {
+            if item == READ_MARKER { return .read }
+            if item == WRITE_MARKER { return .write }
+            return .readWrite
+        }
+    }
+}

damus/Nostr/Id.swift

@@ -34,6 +34,19 @@ protocol TagConvertible {
     static func from_tag(tag: TagSequence) -> Self?
 }
 
+/// Protocol for types that can be converted from/to a tag sequence with the possibilty of an error
+protocol ThrowingTagConvertible {
+    associatedtype E: Error
+    var tag: [String] { get }
+    static func fromTag(tag: TagSequence) throws(E) -> Self?
+}
+
+/// Protocol for types that can be converted from/to a tag item
+protocol TagItemConvertible {
+    var tagItem: String? { get }
+    static func fromTagItem(_ item: String?) -> Self?
+}
+
 struct QuoteId: IdType, TagKey, TagConvertible {
     let id: Data
     

damus/Nostr/NostrKind.swift

@@ -19,6 +19,7 @@ enum NostrKind: UInt32, Codable {
     case like = 7
     case chat = 42
     case mute_list = 10000
+    case relay_list = 10002
     case list_deprecated = 30000
     case draft = 31234
     case longform = 30023

damus/Nostr/Relay.swift

@@ -17,6 +17,15 @@ public struct LegacyKind3RelayRWConfiguration: Codable, Sendable {
     }
 
     static let rw = LegacyKind3RelayRWConfiguration(read: true, write: true)
+    
+    func toNIP65RWConfiguration() -> NIP65.RelayList.RelayItem.RWConfiguration? {
+        switch (self.read, self.write) {
+        case (false, true): return .write
+        case (true, false): return .read
+        case (true, true): return .readWrite
+        default: return nil
+        }
+    }
 }
 
 enum RelayVariant {
@@ -162,3 +171,26 @@ extension RelayPool {
         case RelayAlreadyExists
     }
 }
+
+
+// MARK: - Extension to bridge NIP-65 relay list structs with app-native objects
+
+extension NIP65.RelayList {
+    static func fromLegacyContactList(_ contactList: NdbNote) throws(BridgeError) -> Self {
+        guard let relayListInfo = decode_json_relays(contactList.content) else { throw .couldNotDecodeRelayListInfo }
+        let relayItems = relayListInfo.map({ url, rwConfiguration in
+            return RelayItem(url: url, rwConfiguration: rwConfiguration.toNIP65RWConfiguration() ?? .readWrite)
+        })
+        return NIP65.RelayList(relays: relayItems)
+    }
+    
+    static func fromLegacyContactList(_ contactList: NdbNote?) throws(BridgeError) -> Self? {
+        guard let contactList = contactList else { return nil }
+        return try fromLegacyContactList(contactList)
+    }
+    
+    enum BridgeError: Error {
+        case couldNotDecodeRelayListInfo
+    }
+}
+

damus/Views/LoadableNostrEventView.swift

@@ -74,7 +74,7 @@ class LoadableNostrEventViewModel: ObservableObject {
             case .zap, .zap_request:
                 guard let zap = await get_zap(from: ev, state: damus_state) else { return .not_found }
                 return .loaded(route: Route.Zaps(target: zap.target))
-            case .contacts, .metadata, .delete, .boost, .chat, .mute_list, .list_deprecated, .draft, .longform, .nwc_request, .nwc_response, .http_auth, .status:
+            case .contacts, .metadata, .delete, .boost, .chat, .mute_list, .list_deprecated, .draft, .longform, .nwc_request, .nwc_response, .http_auth, .status, .relay_list:
                 return .unknown_or_unsupported_kind
             }
         case .naddr(let naddr):