From 4d3c0b0e7513168044625292ef3a5149b7c8925d Mon Sep 17 00:00:00 2001
From: Vlad <13818348+walldiss@users.noreply.github.com>
Date: Thu, 26 Jan 2023 17:04:57 +0300
Subject: [PATCH] feat(share/discovery): Ensure only one instance of
 EnsurePeers is running (#1642)

ensure only one instance of EnsurePeers is running
---
 share/availability/discovery/discovery.go | 10 ++++++++++
 share/availability/full/availability.go   |  2 +-
 share/availability/light/availability.go  |  2 +-
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/share/availability/discovery/discovery.go b/share/availability/discovery/discovery.go
index 95e8e3b7a8..b27123a6f7 100644
--- a/share/availability/discovery/discovery.go
+++ b/share/availability/discovery/discovery.go
@@ -2,6 +2,7 @@ package discovery
 
 import (
 	"context"
+	"sync"
 	"time"
 
 	logging "github.com/ipfs/go-log/v2"
@@ -41,6 +42,8 @@ type Discovery struct {
 	advertiseInterval time.Duration
 	// onUpdatedPeers will be called on peer set changes
 	onUpdatedPeers OnUpdatedPeers
+	// ensureIsRunning allows only one ensurePeers process to be running
+	ensurePeersOnce sync.Once
 }
 
 type OnUpdatedPeers func(peerID peer.ID, isAdded bool)
@@ -62,6 +65,7 @@ func NewDiscovery(
 		discInterval,
 		advertiseInterval,
 		func(peer.ID, bool) {},
+		sync.Once{},
 	}
 }
 
@@ -102,6 +106,12 @@ func (d *Discovery) handlePeerFound(ctx context.Context, topic string, peer peer
 // It starts peer discovery every 30 seconds until peer cache reaches peersLimit.
 // Discovery is restarted if any previously connected peers disconnect.
 func (d *Discovery) EnsurePeers(ctx context.Context) {
+	d.ensurePeersOnce.Do(func() {
+		go d.ensurePeers(ctx)
+	})
+}
+
+func (d *Discovery) ensurePeers(ctx context.Context) {
 	if d.peersLimit == 0 {
 		log.Warn("peers limit is set to 0. Skipping discovery...")
 		return
diff --git a/share/availability/full/availability.go b/share/availability/full/availability.go
index f6ef1ff05f..9a0ce67f70 100644
--- a/share/availability/full/availability.go
+++ b/share/availability/full/availability.go
@@ -37,7 +37,7 @@ func (fa *ShareAvailability) Start(context.Context) error {
 	fa.cancel = cancel
 
 	go fa.disc.Advertise(ctx)
-	go fa.disc.EnsurePeers(ctx)
+	fa.disc.EnsurePeers(ctx)
 	return nil
 }
 
diff --git a/share/availability/light/availability.go b/share/availability/light/availability.go
index f804a91e32..3519ae1c8a 100644
--- a/share/availability/light/availability.go
+++ b/share/availability/light/availability.go
@@ -44,7 +44,7 @@ func (la *ShareAvailability) Start(context.Context) error {
 	ctx, cancel := context.WithCancel(context.Background())
 	la.cancel = cancel
 
-	go la.disc.EnsurePeers(ctx)
+	la.disc.EnsurePeers(ctx)
 	return nil
 }