From f38f14b926f5ff473c98f6aaa26c933984c61665 Mon Sep 17 00:00:00 2001
From: Vladislav Veselskiy <v.veselskiy@bit.games>
Date: Wed, 29 Jan 2025 11:51:28 +0300
Subject: [PATCH] Add comment.

---
 message.go | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/message.go b/message.go
index b80b82a..42a1ad9 100644
--- a/message.go
+++ b/message.go
@@ -1,9 +1,12 @@
 package fcm
 
 type Message struct {
-	Token        string            `json:"token,omitempty"`
-	Topic        string            `json:"topic,omitempty"`
-	Condition    string            `json:"condition,omitempty"`
+	// Union field target can be only one of the following:
+	Token     string `json:"token,omitempty"`
+	Topic     string `json:"topic,omitempty"`
+	Condition string `json:"condition,omitempty"`
+	// End of list of possible types for union field target.
+
 	Data         map[string]string `json:"data,omitempty"`
 	Notification *Notification     `json:"notification,omitempty"`
 	FcmOptions   *FcmOptions       `json:"fcm_options,omitempty"`