v2.1.28 - Add kind-3 fallback for relay discovery (NIP-65 pre-standard relay lists in contact list r tags)

caching/src/relay_discovery.c

@@ -239,8 +239,8 @@ static void compute_covering_set(cr_relay_map_t *map, cr_config_t *cfg,
  * Returns a cJSON array of events (caller must cJSON_Delete each + free).
  * Sets *out_count to the number of events returned. */
 static cJSON **query_kind10002_batch(nostr_relay_pool_t *pool,
-                                     const char **pubkeys, int pubkey_count,
-                                     int *out_count) {
+                                      const char **pubkeys, int pubkey_count,
+                                      int *out_count) {
     cJSON *filter = cJSON_CreateObject();
     cJSON *authors = cJSON_CreateArray();
     for (int i = 0; i < pubkey_count; i++)
@@ -276,6 +276,44 @@ static cJSON **query_kind10002_batch(nostr_relay_pool_t *pool,
     return events;
 }
 
+/* ---- batched kind-3 fallback query ---- */
+
+/* Query kind 3 (contact list) for a batch of pubkeys from a pool.
+ * Kind-3 events historically contain "r" tags with relay URLs (pre-NIP-65).
+ * We use this as a fallback for pubkeys that don't have kind-10002.
+ * Returns a cJSON array of events (caller must cJSON_Delete each + free).
+ * Sets *out_count to the number of events returned. */
+static cJSON **query_kind3_batch(nostr_relay_pool_t *pool,
+                                  const char **pubkeys, int pubkey_count,
+                                  int *out_count) {
+    cJSON *filter = cJSON_CreateObject();
+    cJSON *authors = cJSON_CreateArray();
+    for (int i = 0; i < pubkey_count; i++)
+        cJSON_AddItemToArray(authors, cJSON_CreateString(pubkeys[i]));
+    cJSON_AddItemToObject(filter, "authors", authors);
+    cJSON *kinds = cJSON_CreateArray();
+    cJSON_AddItemToArray(kinds, cJSON_CreateNumber(3));
+    cJSON_AddItemToObject(filter, "kinds", kinds);
+    /* limit=1 per author: we only need the most recent kind-3.
+     * The relay pool query_sync returns the most recent events. */
+    cJSON_AddItemToObject(filter, "limit", cJSON_CreateNumber(pubkey_count));
+
+    const char **urls = NULL;
+    int n = get_pool_urls(pool, &urls);
+
+    DEBUG_TRACE("query_kind3_batch: querying %d relays for %d pubkeys", n, pubkey_count);
+
+    int ev_count = 0;
+    cJSON **events = nostr_relay_pool_query_sync(pool, urls, n, filter, &ev_count, 30000);
+    free(urls);
+    cJSON_Delete(filter);
+
+    DEBUG_TRACE("query_kind3_batch: returned %d events", ev_count);
+
+    *out_count = ev_count;
+    return events;
+}
+
 /* Process a batch of kind-10002 events: parse r-tags, populate outbox entries,
  * publish to local relay. Returns count of events processed. */
 static int process_10002_batch(cJSON **events, int ev_count,
@@ -438,9 +476,61 @@ int cr_relay_discovery_run(cr_relay_map_t *map, cr_config_t *cfg,
         free(remaining_pk);
     }
 
+    /* Phase 3: Kind-3 fallback for pubkeys still without relay lists.
+     * Kind-3 (contact list) events historically contain "r" tags with relay
+     * URLs (pre-NIP-65). This catches older users who never published kind-10002. */
+    int remaining_k3 = 0;
+    for (int i = 0; i < followed->count; i++) if (!found[i]) remaining_k3++;
+
+    if (remaining_k3 > 0) {
+        DEBUG_INFO("relay_discovery: querying bootstrap relays for kind-3 fallback (%d pubkeys)...",
+                    remaining_k3);
+
+        const char **remaining_pk = malloc(remaining_k3 * sizeof(char *));
+        int ridx = 0;
+        for (int i = 0; i < followed->count; i++) {
+            if (!found[i]) remaining_pk[ridx++] = followed->items[i];
+        }
+
+        int found_k3 = 0;
+        for (int start = 0; start < remaining_k3 && !g_shutdown; start += CR_10002_BATCH_SIZE) {
+            int batch = remaining_k3 - start;
+            if (batch > CR_10002_BATCH_SIZE) batch = CR_10002_BATCH_SIZE;
+
+            int ev_count = 0;
+            cJSON **events = query_kind3_batch(upstream,
+                                                &remaining_pk[start],
+                                                batch, &ev_count);
+            if (events && ev_count > 0) {
+                for (int k = 0; k < ev_count; k++) {
+                    cJSON *pk = cJSON_GetObjectItem(events[k], "pubkey");
+                    if (pk && cJSON_IsString(pk)) {
+                        const char *hex = cJSON_GetStringValue(pk);
+                        for (int i = 0; i < followed->count; i++) {
+                            if (strcmp(followed->items[i], hex) == 0) {
+                                if (!found[i]) { found[i] = 1; found_k3++; }
+                                break;
+                            }
+                        }
+                    }
+                }
+                /* process_10002_batch works for kind-3 too — same r-tag format */
+                process_10002_batch(events, ev_count, map, sink, "bootstrap");
+                cr_sink_pump(sink, 500);
+            } else {
+                free(events);
+            }
+        }
+        free(remaining_pk);
+        DEBUG_INFO("relay_discovery: kind-3 fallback found %d additional pubkeys with relays", found_k3);
+    }
+
     found_none = followed->count - found_local - found_bootstrap;
+    /* Recalculate found_none after kind-3 fallback */
+    int still_none = 0;
+    for (int i = 0; i < followed->count; i++) if (!found[i]) still_none++;
     DEBUG_INFO("relay_discovery: %d local, %d bootstrap, %d none",
-                found_local, found_bootstrap, found_none);
+                found_local, found_bootstrap, still_none);
 
     free(found);
 

src/main.h

@@ -13,8 +13,8 @@
 // Using CRELAY_ prefix to avoid conflicts with nostr_core_lib VERSION macros
 #define CRELAY_VERSION_MAJOR 2
 #define CRELAY_VERSION_MINOR 1
-#define CRELAY_VERSION_PATCH 27
-#define CRELAY_VERSION "v2.1.27"
+#define CRELAY_VERSION_PATCH 28
+#define CRELAY_VERSION "v2.1.28"
 
 // Relay metadata (authoritative source for NIP-11 information)
 #define RELAY_NAME "C-Relay-PG"