node.js - How to prevent multiple reaction by Google Cloud VM instances for one event from Firebase database? -


the problem: dosomething() function, invoked twice (by each running vm instance).

how can react each event 1 vm instance?

node.js script @ google cloud platform:

function listenfornotificationrequests() {     var requests = ref.child('some_node');     requests.on('child_added', function(requestsnapshot) {         var request = requestsnapshot.val();         dosomething(              request.type,            function() {                requestsnapshot.ref.remove();            });     }, function(error) {         console.error(error);     }); };

firebase-queue solves problem, @frank's comment pointed.

multiple queue workers can initialized on multiple machines , firebase-queue ensure 1 worker processing single queue task @ time.


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