Confused about creating text indexes in mgo

[Attila SATAN]

I'm trying to create text indexes with weights but I couldn't figure out how to do by reading API docs.

How can I build indexes as below in mgo.

db.products.createIndex({
  "primaryCategoryIndexes": "text",
  "secondaryCategoryIndexes": "text",
  "brandIndex": "text",
  "primaryTitleIndexes": "text",
  "secondaryTitleIndexes": "text",
  "indexCycleId": "text"
  }, {
    "weights": {
      "primaryCategoryIndexes":10,
      "secondaryCategoryIndexes": 5,
      "brandIndex": 5,
      "primaryTitleIndexes": 5,
      "secondaryTitleIndexes": 5,
      "indexCycleId": 5
  })