relay/main.go

@@ -252,7 +252,7 @@ func main() {
 	mux.HandleFunc("/api/trending/kind20", func(w http.ResponseWriter, r *http.Request) {
 		w.Header().Set("Content-Type", "application/json")
 
-		trendingPosts, err := trending.GetTrendingKind20(db.DB.DB)
+		trendingPosts, err := trending.GetTrendingScoreKind20(db.DB.DB)
 		if err != nil {
 			http.Error(w, fmt.Sprintf("Error getting trending posts: %v", err), http.StatusInternalServerError)
 			return

relay/trending/README.md

@@ -0,0 +1,15 @@
+## Basic
+
+A trending algo over simplified based on reactions
+
+## Score
+
+Add a trending score calculation that considers time decay and multiple engagement types.
+
+Key improvements:
+
+Considers multiple engagement types with different weights
+Implements time decay using a power law function
+Adds a base time offset (7200 seconds = 2 hours) to smooth out early scoring
+More comprehensive trending score instead of just raw counts
+The time decay formula is similar to HackerNews' algorithm but adjusted for shorter-term trending content. You might want to tune the weights and decay factors based on your specific needs.

relay/trending/basic.go

@@ -24,7 +24,7 @@ var (
 )
 
 // GetTrendingKind20 returns the top 20 trending posts of kind 20 from the last 24 hours
-func GetTrendingKind20(db *sql.DB) ([]Post, error) {
+func GetTrendingBasicKind20(db *sql.DB) ([]Post, error) {
 	if cached, ok := trendingCache.Get("trending_kind_20"); ok {
 		return cached.([]Post), nil
 	}

relay/trending/score.go

@@ -0,0 +1,78 @@
+package trending
+
+import (
+	"database/sql"
+	"encoding/json"
+)
+
+// GetTrendingKind20 returns the top 20 trending posts of kind 20 from the last 24 hours
+func GetTrendingScoreKind20(db *sql.DB) ([]Post, error) {
+	if cached, ok := trendingCache.Get("trending_kind_20"); ok {
+		return cached.([]Post), nil
+	}
+
+	query := `
+		WITH engagement AS (
+			SELECT 
+				tags_expanded.value->1 #>> '{}' AS original_event_id,
+				e.kind::text,
+				extract(epoch from now()) - e.created_at as seconds_ago,
+				COUNT(*) as count
+			FROM event e
+			CROSS JOIN LATERAL jsonb_array_elements(tags) as tags_expanded(value)
+			WHERE e.kind::text IN ('1', '6', '7')  -- replies, reposts, reactions
+			AND e.created_at >= extract(epoch from now() - interval '24 hours')::bigint
+			AND tags_expanded.value->0 #>> '{}' = 'e'
+			GROUP BY tags_expanded.value->1 #>> '{}', e.kind::text, e.created_at
+		),
+		scores AS (
+			SELECT 
+				original_event_id,
+				SUM(
+					CASE 
+						WHEN kind = '7' THEN count * 1.0  -- reactions weight
+						WHEN kind = '6' THEN count * 2.0  -- reposts weight
+						WHEN kind = '1' THEN count * 1.5  -- replies weight
+					END / power((seconds_ago + 7200) / 3600, 1.8)  -- time decay
+				) as trending_score
+			FROM engagement
+			GROUP BY original_event_id
+		)
+		SELECT 
+			e.id,
+			e.pubkey,
+			to_timestamp(e.created_at) as created_at,
+			e.kind,
+			e.content,
+			e.tags,
+			COALESCE(s.trending_score, 0) as reaction_count
+		FROM event e
+		LEFT JOIN scores s ON e.id = s.original_event_id
+		WHERE e.kind::text = '20'
+		AND e.created_at >= extract(epoch from now() - interval '24 hours')::bigint
+		ORDER BY reaction_count DESC, e.created_at DESC
+		LIMIT 20
+	`
+
+	rows, err := db.Query(query)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var trendingPosts []Post
+	for rows.Next() {
+		var post Post
+		var tagsJSON []byte
+		if err := rows.Scan(&post.ID, &post.PubKey, &post.CreatedAt, &post.Kind, &post.Content, &tagsJSON, &post.ReactionCount); err != nil {
+			return nil, err
+		}
+		if err := json.Unmarshal(tagsJSON, &post.Tags); err != nil {
+			return nil, err
+		}
+		trendingPosts = append(trendingPosts, post)
+	}
+
+	trendingCache.Set("trending_kind_20", trendingPosts, cacheDuration)
+	return trendingPosts, nil
+}