Bulk upserting with $addToSet in mongo

Question

Good Afternoon Everyone,

I have a question regarding upserting arrays to Mongo.

Let's use the following data as an example:

[{ 
  name: 'Charlie Brown',
  companies: ['xyz', 'abc'],
  data: {
    City: 'PHOENIX'
  } 
},
{ 
  name: 'Alex Brown',
  companies: ['xyz', 'ghj'],
  data: {
    State: 'GA'
  } 
},
{ 
  name: 'Charlie Brown',
  companies: ['abc', 'yui'],
  data: {
    City: 'FLINT',
    State: 'GA'
  } 
}]

The actual records are a bit more complex and more numerous than 3, but I hope this will serve sufficiently.

I want to insert/update/upsert these records into a mongoDB where matches (updates) do not overwrite the properties, but instead use $addToSet.

The end result should look like this:

[{ 
  name: 'Charlie Brown',
  companies: ['xyz', 'abc', 'yui'],
  data: {
    City: ['PHOENIX', 'FLINT'],
    STATE: 'GA'
  } 
},
{ 
  name: 'Alex Brown',
  companies: ['xyz', 'ghj'],
  data: {
    State: 'GA'
  } 
}]

I'm having a bit of trouble figuring out the correct mongo syntax for this. I know there is an upsert option on update, but how do I supply an array of records I would like to update, and then update individual records in the array?

I thought maybe the idea is to gather a set of names from the records, so

['Charlie Brown', 'Alex Brown']

and then use that set as a query field,

mongo.collection.update({
    ['Charlie Brown', 'Alex Brown'],
    {$addToSet:{companies: ??? what do I put here??}},
    {upsert: true}
})

What is the correct syntax (or correct method, perhaps using aggregations) to insert/update these records into Mongo?

Thank you!

Note: this question has similarities to Bulk upsert in MongoDB using mongoose , but the key here is also using the modifier $addToSet. Also, those solutions place the DB operation within a loop, is this normal with mongo?