Question

I’m trying to insert/update an array of strings in a mongodb document using some typescript code running in NodeJS.
The following code is typescript but I guess JS developers will get it w/o any problems:

export function addEvents(entityId: string, 
                          events: string[] , 
                          callback: () => void) {

   db.collection('events', function(error, eventCollection) {
       if(error) { 
           console.error(error); return; 
       }
       eventCollection.update({ _id: entityId }, { "$pushAll ": 
       { events: events }},
           function(error, result) {
               if(error) { 
                   console.error(error); return; 
               }
               callback();
           });
   });
}

the document have the following structure:

{
    _id : string
    events : ["array","of","strings"]
}

I simply want to append an array strings at the end of the existing array for a specific _id.

I don’t quite get if I should use update,save, $push ,$pushall etc.

Can someone explain?

Answer 1

Found the problem, I needed to pass “{ upsert = true }” as a third argument to the update function.