Lounge

Indexing on embedded documents

Finally, indexing can be accomplished on embedded documents.

var companySchema = lounge.schema({
  id: { type: String, key: true, generate: false },
  name: String
})

var userSchema = lounge.schema({
  email: { type: String, key: true, generate: false },
  company: { type: Company, index: true }
})

// ...

var company = new Company({ id: 'acme_inc.', name: 'Acme Inc.' })
var user = new User({ email: 'bob@gmail.com', company: company })

Here a lookup reference document will be created with key '$_ref_by_company_acme_inc.' and it will link to our User document:

{ "key": "bob@gmail.com" }

We can use User.findByCompany(company.id, ...) to get the User instance.

This example probably doesn't make much sense in real world. Multiple users can be associated with the same company, so we really should use the 'array' index type.

var companySchema = lounge.schema({
  id: { type: String, key: true, generate: false },
  name: String
})

var userSchema = lounge.schema({
  email: { type: String, key: true, generate: false },
  company: { type: Company, index: true, indexType: 'array' }
})

// ...

var company = new Company({ id: 'acme_inc.', name: 'Acme Inc.' })
var user1 = new User({ email: 'bob@gmail.com', company: company })
var user2 = new User({ email: 'joe@outlook.com', company: company })

Here now the company lookup reference document will have contents:

"keys": [
  "bob@gmail.com",
  "joe@outlook.com"
]

We can use User.findByCompany(company.id, ...) to get both User instances.

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