added discord template

notify_templates/notify_discord.sh

@@ -0,0 +1,25 @@
+### DISCLAIMER: This is a third party addition to dockcheck - best effort testing.
+#
+# Copy/rename this file to notify.sh to enable the notification snippet.
+# Required receiving services must already be set up.
+# Modify to fit your setup - set DiscordWebhookUrl
+
+send_notification() {
+    [ -s "$ScriptWorkDir"/urls.list ] && releasenotes || Updates=("$@")
+    UpdToString=$( printf '%s\\n' "${Updates[@]}" )
+
+    echo "$UpdToString"
+    FromHost=$(hostname)
+
+    # platform specific notification code would go here
+    printf "\nSending Discord notification\n"
+
+    # Setting the MessageBody variable here.
+    MessageBody="🐋 Containers on $FromHost with updates available: \n$UpdToString"
+
+    # Modify to fit your setup:
+    DiscordWebhookUrl="PasteYourFullDiscordWebhookURL"
+
+    MsgBody="{\"username\":\"$FromHost\",\"content\":\"$MessageBody\"}"
+    curl -sS -o /dev/null --fail -X POST -H "Content-Type: application/json" -d "$MsgBody" "$DiscordWebhookUrl"
+