From 0b9778d6cac66c1c606e9629341947406082b6e0 Mon Sep 17 00:00:00 2001
From: Greg Heartsfield <scsibug@imap.cc>
Date: Sat, 17 Dec 2022 20:46:58 -0600
Subject: [PATCH] refactor: simplify tracking of subscriptions

---
 src/conn.rs   |  5 +++++
 src/server.rs | 12 ++----------
 2 files changed, 7 insertions(+), 10 deletions(-)

diff --git a/src/conn.rs b/src/conn.rs
index bd41696..4b7e0ba 100644
--- a/src/conn.rs
+++ b/src/conn.rs
@@ -46,6 +46,11 @@ impl ClientConn {
         &self.subscriptions
     }
 
+    /// Check if the given subscription already exists
+    pub fn has_subscription(&self, sub: &Subscription) -> bool {
+        self.subscriptions.values().any(|x| x == sub)
+    }
+
     /// Get a short prefix of the client's unique identifier, suitable
     /// for logging.
     #[must_use]
diff --git a/src/server.rs b/src/server.rs
index 10d98ca..f94aece 100644
--- a/src/server.rs
+++ b/src/server.rs
@@ -476,8 +476,6 @@ async fn nostr_server(
     // when these subscriptions are cancelled, make a message
     // available to the executing query so it knows to stop.
     let mut running_queries: HashMap<String, oneshot::Sender<()>> = HashMap::new();
-    // keep track of the subscriptions we have
-    let mut current_subs: Vec<Subscription> = Vec::new();
     // for stats, keep track of how many events the client published,
     // and how many it received from queries.
     let mut client_published_event_count: usize = 0;
@@ -625,11 +623,10 @@ async fn nostr_server(
                         // * making a channel to cancel to request later
                         // * sending a request for a SQL query
             // Do nothing if the sub already exists.
-            if !current_subs.contains(&s) {
+            if !conn.has_subscription(&s) {
                 if let Some(ref lim) = sub_lim_opt {
-                    lim.until_ready_with_jitter(jitter).await;
+                lim.until_ready_with_jitter(jitter).await;
                 }
-                current_subs.push(s.clone());
                             let (abandon_query_tx, abandon_query_rx) = oneshot::channel::<()>();
                             match conn.subscribe(s.clone()) {
                 Ok(()) => {
@@ -653,11 +650,6 @@ async fn nostr_server(
                         // closing a request simply removes the subscription.
                         let parsed : Result<Close> = Result::<Close>::from(cc);
             if let Ok(c) = parsed {
-                                // remove from the list of known subs
-                if let Some(pos) = current_subs.iter().position(|s| *s.id == c.id) {
-                current_subs.remove(pos);
-                }
-
                                 // check if a query is currently
                                 // running, and remove it if so.
                                 let stop_tx = running_queries.remove(&c.id);