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attributes

Attributes are usually set as part of create or update calls, or directly using dot notation (balloon.color = 'red' and then calling balloon.save); however, there are times (e.g. when adding custom getters and setters that transform the data prior to persisting) when it is helpful to bypass the getters and setters.

Decimal columns​

PostgreSQL numeric/decimal columns return JavaScript number — not string or a Decimal wrapper. Dream's type-sync converts these to TypeScript number, so DreamColumn<Place, 'latitude'> resolves to number | null (or number if NOT NULL). No Number(value) coercion is needed when reading.

To control how many decimal places appear in a response, use the precision option on the serializer attribute rather than rounding in application code. This keeps the OpenAPI shape and rendered output consistent:

// In your serializer
.attribute('latitude', { precision: 7 })
.attribute('price', { precision: 2 })
// Also works on delegatedAttribute
.delegatedAttribute('place', 'latitude', { precision: 7 })

This handles the common floating-point quirk where 1.1 + 2.2 becomes 3.3000000000000003 — a value that rounds cleanly to 3.30 at the precision the schema actually cares about.

Branching on enum values​

When branching on a database enum column, always use an exhaustive switch with a const _never: never default — never an if/else if chain. Database enums regenerated into @src/types/db.js are closed sets: an if/else if chain silently no-ops when a new enum value is added, while the _never default turns a missing case into a compile error.

const style = place.style  // e.g. PlaceStylesEnum
switch (style) {
  case 'cabin':
    return handleCabin(place)
  case 'cottage':
    return handleCottage(place)
  case 'apartment':
    return handleApartment(place)
  default: {
    const _never: never = style
    throw new Error(`Unhandled style: ${String(_never)}`)
  }
}

This rule applies to any closed union of string literals: database enums, STI type discriminators, or any other union declared in code.

Bypassing methods​

getAttributes​

Returns an object containing all the columns on this Dream class, as well as their values, bypassing getters:

const user = User.new({ email: 'how@yadoin' })
user.getAttributes()
// {
//   email: 'how@yadoin',
//   ...
// }

getAttribute​

Returns the value for a columnName provided, bypassing the getters:

const user = User.new({ email: 'how@yadoin' })
user.getAttribute('email')
// 'how@yadoin'

setAttributes​

Takes the attributes passed in and sets their values internally, bypassing custom setters defined for these attributes:

const user = new User()
user.setAttributes({ email: 'my@email', password: 'my password' })

setAttribute​

Changes the attribute value for a single attribute internally, bypassing custom-defined setters:

const user = new User()
user.setAttribute('email', 'sally@gmail.com')

Non-bypassing methods​

assignAttributes​

Takes the attributes passed in and sets their values, leveraging custom setters defined for these attributes:

const user = new User()
user.assignAttributes({ email: 'my@email', password: 'my password' })

assignAttribute​

Changes the attribute value for a single attribute, leveraging custom-defined setters.

const user = new User()
user.assignAttribute('email', 'sally@gmail.com')