From 8a06ec5131bb24c6fa14a18318439493369b4f83 Mon Sep 17 00:00:00 2001
From: Peter Saxton <peterhsaxton@gmail.com>
Date: Fri, 7 Jan 2022 09:37:06 +0100
Subject: [PATCH] channel only needs to be able to read

---
 client_sub.go   | 2 +-
 subscription.go | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/client_sub.go b/client_sub.go
index 48efd214..5ea54474 100644
--- a/client_sub.go
+++ b/client_sub.go
@@ -16,7 +16,7 @@ import (
 // Subscribe creates a Subscription with given parameters.
 // Parameters that have not been set are set to their default values.
 // See opcua.DefaultSubscription* constants
-func (c *Client) Subscribe(params *SubscriptionParameters, notifyCh chan *PublishNotificationData) (*Subscription, error) {
+func (c *Client) Subscribe(params *SubscriptionParameters, notifyCh chan<- *PublishNotificationData) (*Subscription, error) {
 	stats.Client().Add("Subscribe", 1)
 
 	if params == nil {
diff --git a/subscription.go b/subscription.go
index 5b0699b1..3b9ca088 100644
--- a/subscription.go
+++ b/subscription.go
@@ -29,7 +29,7 @@ type Subscription struct {
 	RevisedPublishingInterval time.Duration
 	RevisedLifetimeCount      uint32
 	RevisedMaxKeepAliveCount  uint32
-	Notifs                    chan *PublishNotificationData
+	Notifs                    chan<- *PublishNotificationData
 	params                    *SubscriptionParameters
 	items                     map[uint32]*monitoredItem
 	itemsMu                   sync.Mutex