From 1804bee912f1b01009501e31c715fbe7c072f41e Mon Sep 17 00:00:00 2001
From: Greg Heartsfield <scsibug@imap.cc>
Date: Sat, 28 Jan 2023 17:09:21 -0600
Subject: [PATCH] feat(NIP-33): parameterized replaceable events for postgres

---
 src/repo/postgres.rs | 30 +++++++++++++++++++++++++++++-
 src/repo/sqlite.rs   |  1 +
 src/server.rs        | 11 +++++++++--
 3 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/src/repo/postgres.rs b/src/repo/postgres.rs
index 1991be2..8391b89 100644
--- a/src/repo/postgres.rs
+++ b/src/repo/postgres.rs
@@ -133,7 +133,34 @@ ON CONFLICT (id) DO NOTHING"#,
                 );
             }
         }
-
+        // parameterized replaceable events
+        // check for parameterized replaceable events that would be hidden; don't insert these either.
+        if let Some(d_tag) = e.distinct_param() {
+            let update_count;
+            if is_lower_hex(&d_tag) && (d_tag.len() % 2 == 0) {
+                update_count = sqlx::query("DELETE FROM event WHERE kind=$1 AND pub_key=$2 AND id NOT IN (SELECT e.id FROM event e LEFT JOIN tag t ON e.id=t.event_id WHERE e.kind=$1 AND e.pub_key=$2 AND t.name='d' AND t.value_hex=$3 ORDER BY created_at DESC LIMIT 1);")
+                    .bind(e.kind as i64)
+                    .bind(hex::decode(&e.pubkey).ok())
+                    .bind(hex::decode(d_tag).ok())
+                    .execute(&mut tx)
+                    .await?.rows_affected();
+            } else {
+                update_count = sqlx::query("DELETE FROM event WHERE kind=$1 AND pub_key=$2 AND id NOT IN (SELECT e.id FROM event e LEFT JOIN tag t ON e.id=t.event_id WHERE e.kind=$1 AND e.pub_key=$2 AND t.name='d' AND t.value=$3 ORDER BY created_at DESC LIMIT 1);")
+                    .bind(e.kind as i64)
+                    .bind(hex::decode(&e.pubkey).ok())
+                    .bind(d_tag.as_bytes())
+                    .execute(&mut tx)
+                    .await?.rows_affected();
+            }
+            if update_count > 0 {
+                info!(
+                    "removed {} older parameterized replaceable kind {} events for author: {:?}",
+                    update_count,
+                    e.kind,
+                    e.get_author_prefix()
+                );
+            }
+        }
         // if this event is a deletion, hide the referenced events from the same author.
         if e.kind == 5 {
             let event_candidates = e.tag_values_by_name("e");
@@ -300,6 +327,7 @@ ON CONFLICT (id) DO NOTHING"#,
                 // TODO: we could use try_send, but we'd have to juggle
                 // getting the query result back as part of the error
                 // result.
+                metrics.sent_events.inc();
                 query_tx
                     .send(QueryResult {
                         sub_id: sub.get_id(),
diff --git a/src/repo/sqlite.rs b/src/repo/sqlite.rs
index bdd21ac..299f047 100644
--- a/src/repo/sqlite.rs
+++ b/src/repo/sqlite.rs
@@ -420,6 +420,7 @@ impl NostrRepo for SqliteRepo {
                     // TODO: we could use try_send, but we'd have to juggle
                     // getting the query result back as part of the error
                     // result.
+                    metrics.sent_events.inc();
                     query_tx
                         .blocking_send(QueryResult {
                             sub_id: sub.get_id(),
diff --git a/src/server.rs b/src/server.rs
index 9fffd07..e64b946 100644
--- a/src/server.rs
+++ b/src/server.rs
@@ -321,21 +321,27 @@ pub fn start_server(settings: &Settings, shutdown_rx: MpscReceiver<()>) -> Resul
             "write_event",
             "Event writing response times",
         )).unwrap();
+        let sent_events = IntCounter::with_opts(Opts::new(
+            "sent_event",
+            "Events sent",
+        )).unwrap();
         let connections = IntCounter::with_opts(Opts::new(
             "connections",
-            "New connections"
+            "New connections",
         )).unwrap();
         let query_aborts = IntCounter::with_opts(Opts::new(
             "query_abort",
-            "Aborted queries"
+            "Aborted queries",
         )).unwrap();
         registry.register(Box::new(query_sub.clone())).unwrap();
         registry.register(Box::new(write_events.clone())).unwrap();
+        registry.register(Box::new(sent_events.clone())).unwrap();
         registry.register(Box::new(connections.clone())).unwrap();
         registry.register(Box::new(query_aborts.clone())).unwrap();
         let metrics = NostrMetrics {
             query_sub,
             write_events,
+            sent_events,
             connections,
             query_aborts,
         };
@@ -783,6 +789,7 @@ async fn nostr_server(
 pub struct NostrMetrics {
     pub query_sub: Histogram,
     pub write_events: Histogram,
+    pub sent_events: IntCounter,
     pub connections: IntCounter,
     pub query_aborts: IntCounter,
 }