使用Cloud Functions for Firebase检查名称是否存在

Question

How do I check if a name exists using Cloud Functions for Firebase?

I have the following data structure:

And this pseudo-code:

exports.addIt = functions.database.ref('/messages/{pushId}')
.onWrite(event => {

if(creationDate does not exist)
event.data.adminRef.update({"creationDate":Date.now()})

else // do not update anything

})

I want to check if 'creationDate' already exists or not. How do I achieve that?

Answer 1

Something like this :-

exports.addIt = functions.database.ref('/messages/{pushId}')
.onWrite(event => {
if(typeof event.data.val().creationDate != 'undefined')
return event.data.adminRef.update({"creationDate":Date.now()})

else // do not update anything

})