Updating an array item using NodeJS, MongoDB & Monk

Question

I have a data set like this:

{ 
  name : 'Doc Name',
  photos: [
      {
        name: 'photo1',
        url: 'http://.....'
      },
      {
        name: 'photo2',
        url: 'http://......'
      }
   ],
   etc ...

Using Monk https://github.com/LearnBoost/monk how do I update photo2? I can use an index as I am iterating over the fields at the moment.

My current attempt below gives me an error, and I can't use a variable for the JSON selector (as in the index).

collection.update({_id: data._id}, {photos[i].data: filename}, function(err, updatedata) {

            });

Answer 1

Updating items at a position in an array can be done using the positional $ operator

collection.update( 
    { _id: data.id, "photos.name": "photo2" }, 
    { $set: { "photos.$.data": "yourdata" } }
)