From d175e30fcdb07c59295062a0da1ab51defe7f2de Mon Sep 17 00:00:00 2001
From: Yasuhiro Matsumoto <mattn.jp@gmail.com>
Date: Sat, 2 Dec 2023 19:14:54 +0900
Subject: [PATCH] reconnect

---
 pool.go | 103 ++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 63 insertions(+), 40 deletions(-)

diff --git a/pool.go b/pool.go
index f10ea7c..8bb50ea 100644
--- a/pool.go
+++ b/pool.go
@@ -79,20 +79,19 @@ func (pool *SimplePool) subMany(ctx context.Context, urls []string, filters Filt
 	ticker := time.NewTicker(seenAlreadyDropTick)
 	eose := false
 
+	updateSince := func() {
+		// After reconnection, update the since in the filter so that
+		// old events are not retrieved.
+		now := Now()
+		for i := range filters {
+			filters[i].Since = &now
+		}
+	}
+
 	pending := xsync.NewCounter()
 	pending.Add(int64(len(urls)))
 	for _, url := range urls {
 		go func(nm string) {
-			relay, err := pool.EnsureRelay(nm)
-			if err != nil {
-				return
-			}
-
-			sub, _ := relay.Subscribe(ctx, filters)
-			if sub == nil {
-				return
-			}
-
 			defer func() {
 				pending.Dec()
 				if pending.Value() == 0 {
@@ -103,41 +102,65 @@ func (pool *SimplePool) subMany(ctx context.Context, urls []string, filters Filt
 
 			for {
 				select {
-				case evt, more := <-sub.Events:
-					if !more {
-						return
-					}
-					if unique {
-						if _, seen := seenAlready.LoadOrStore(evt.ID, evt.CreatedAt); seen {
-							continue
-						}
-					}
+				case <-ctx.Done():
+					return
+				default:
+				}
+
+				relay, err := pool.EnsureRelay(nm)
+				if err != nil {
+					time.Sleep(3 * time.Second)
+					updateSince()
+					continue
+				}
+
+				sub, err := relay.Subscribe(ctx, filters)
+				if err != nil {
+					time.Sleep(3 * time.Second)
+					updateSince()
+					continue
+				}
+
+			loop:
+				for {
 					select {
-					case events <- IncomingEvent{Event: evt, Relay: relay}:
-					case <-ctx.Done():
-					}
-				case <-sub.EndOfStoredEvents:
-					eose = true
-				case <-ticker.C:
-					if eose {
-						del := map[string]struct{}{}
-						old := Timestamp(time.Now().Add(-seenAlreadyDropTick).Unix())
-						seenAlready.Range(func(id string, value Timestamp) bool {
-							if value < old {
-								del[id] = struct{}{}
+					case evt, more := <-sub.Events:
+						if !more {
+							break loop
+						}
+						if unique {
+							if _, seen := seenAlready.LoadOrStore(evt.ID, evt.CreatedAt); seen {
+								continue
 							}
-							return true
-						})
-						for k := range del {
-							seenAlready.Delete(k)
 						}
+						select {
+						case events <- IncomingEvent{Event: evt, Relay: relay}:
+						case <-ctx.Done():
+						}
+					case <-sub.EndOfStoredEvents:
+						eose = true
+					case <-ticker.C:
+						if eose {
+							del := map[string]struct{}{}
+							old := Timestamp(time.Now().Add(-seenAlreadyDropTick).Unix())
+							seenAlready.Range(func(id string, value Timestamp) bool {
+								if value < old {
+									del[id] = struct{}{}
+								}
+								return true
+							})
+							for k := range del {
+								seenAlready.Delete(k)
+							}
+						}
+					case reason := <-sub.ClosedReason:
+						log.Printf("CLOSED from %s: '%s'\n", nm, reason)
+						return
+					case <-ctx.Done():
+						return
 					}
-				case reason := <-sub.ClosedReason:
-					log.Printf("CLOSED from %s: '%s'\n", nm, reason)
-					return
-				case <-ctx.Done():
-					return
 				}
+				updateSince()
 			}
 		}(NormalizeURL(url))
 	}