Hi,

For safety use, it's better to have null check for all variables which are used in this function.

if (!_sessionPriv.$clientAlarmList) {
    return;
}

↓

if (!_sessionPriv.$clientAlarmList
     || !_sessionPriv.$monitoredItemForAlarmList
     || !_sessionPriv.$subscriptionforAlarmList ) {
    return;
}

https://github.com/node-opcua/node-opcua/blob/master/pack

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Solution 2

• Wor

In light of the gradual demise of CQEx in favor of Xandra, astarte_pairing should be adapted to use Xandra instead of CQEx.

This mainly translates to:

• Add Xandra as a dependency
• Start the Xandra connection
• Translate all queries from CQEx to Xandra, both in lib and in test.

To see an example of a service already using Xandra, have a look at astarte_housekeeping (and this PR h