Question

I want to upsert a document with the mongo-ruby-driver using something like the following-

id = "#{params[:id]}:#{Time.now.strftime("%y%m%d")}"
# db.collection('metrics').insert({'_id' => id})
db.collection('metrics').update(
  { '_id' => id },
  { '$inc' => { "hits" => 1 } },
  { 'upsert' => true }
)

Right now this will only update existing documents, and not create one if it doesn’t already exist. The only way it will perform both actions is if I uncomment the insert() command above it.

If I use the mongo console and try and do this upsert directly (without the need for the insert() ) it works as expected.

Answer 1

You should use a symbol instead of string in params. This code works.

db.collection('metrics').update(
  { '_id' => id },
  { '$inc' => { "hits" => 1 } },
  { :upsert => true }
)

In fact, you can use symbols most everywhere. This also works:

db.collection(:metrics).update(
  { :_id => id },
  { :$inc => { :hits => 1 } },
  { :upsert => true }
)