BoostSpec

Boost specification to boost certain documents.

JSON representation 
{
  "conditionBoostSpecs": [
    {
      object (ConditionBoostSpec)
    }
  ]
}
Fields
conditionBoostSpecs[]

object (ConditionBoostSpec)

Condition boost specifications. If a document matches multiple conditions in the specifictions, boost scores from these specifications are all applied and combined in a non-linear way. Maximum number of specifications is 20.

ConditionBoostSpec

Boost applies to documents which match a condition.

JSON representation 
{
  "condition": string,
  "boost": number,
  "boostControlSpec": {
    object (BoostControlSpec)
  }
}
Fields
condition

string

An expression which specifies a boost condition. The syntax and supported fields are the same as a filter expression. See SearchRequest.filter for detail syntax and limitations.

Examples:

  • To boost documents with document ID "doc_1" or "doc_2", and color "Red" or "Blue": (documentId: ANY("doc_1", "doc_2")) AND (color: ANY("Red", "Blue"))
boost

number

Strength of the condition boost, which should be in [-1, 1]. Negative boost means demotion. Default is 0.0.

Setting to 1.0 gives the document a big promotion. However, it does not necessarily mean that the boosted document will be the top result at all times, nor that other documents will be excluded. Results could still be shown even when none of them matches the condition. And results that are significantly more relevant to the search query can still trump your heavily favored but irrelevant documents.

Setting to -1.0 gives the document a big demotion. However, results that are deeply relevant might still be shown. The document will have an upstream battle to get a fairly high ranking, but it is not blocked out completely.

Setting to 0.0 means no boost applied. The boosting condition is ignored. Only one of the (condition, boost) combination or the boostControlSpec below are set. If both are set then the global boost is ignored and the more fine-grained boostControlSpec is applied.
boostControlSpec

object (BoostControlSpec)

Complex specification for custom ranking based on customer defined attribute value.

BoostControlSpec

Specification for custom ranking based on customer specified attribute value. It provides more controls for customized ranking than the simple (condition, boost) combination above.

JSON representation 
{
  "fieldName": string,
  "attributeType": enum (AttributeType),
  "interpolationType": enum (InterpolationType),
  "controlPoints": [
    {
      object (ControlPoint)
    }
  ]
}
Fields
fieldName

string

The name of the field whose value will be used to determine the boost amount.
attributeType

enum (AttributeType)

The attribute type to be used to determine the boost amount. The attribute value can be derived from the field value of the specified fieldName. In the case of numerical it is straightforward i.e. attributeValue = numerical_field_value. In the case of freshness however, attributeValue = (time.now() - datetime_field_value).
interpolationType

enum (InterpolationType)

The interpolation type to be applied to connect the control points listed below.
controlPoints[]

object (ControlPoint)

The control points used to define the curve. The monotonic function (defined through the interpolationType above) passes through the control points listed here.

AttributeType

The attribute(or function) for which the custom ranking is to be applied.

Enums
ATTRIBUTE_TYPE_UNSPECIFIED Unspecified AttributeType.
NUMERICAL The value of the numerical field will be used to dynamically update the boost amount. In this case, the attributeValue (the x value) of the control point will be the actual value of the numerical field for which the boostAmount is specified.
FRESHNESS For the freshness use case the attribute value will be the duration between the current time and the date in the datetime field specified. The value must be formatted as an XSD dayTimeDuration value (a restricted subset of an ISO 8601 duration value). The pattern for this is: [nD][T[nH][nM][nS]]. For example, 5D, 3DT12H30M, T24H.

InterpolationType

The interpolation type to be applied. Default will be linear (Piecewise Linear).

Enums
INTERPOLATION_TYPE_UNSPECIFIED Interpolation type is unspecified. In this case, it defaults to Linear.
LINEAR Piecewise linear interpolation will be applied.

ControlPoint

The control points used to define the curve. The curve defined through these control points can only be monotonically increasing or decreasing(constant values are acceptable).

JSON representation 
{
  "attributeValue": string,
  "boostAmount": number
}
Fields
attributeValue

string

Can be one of: 1. The numerical field value. 2. The duration spec for freshness: The value must be formatted as an XSD dayTimeDuration value (a restricted subset of an ISO 8601 duration value). The pattern for this is: [nD][T[nH][nM][nS]].
boostAmount

number

The value between -1 to 1 by which to boost the score if the attributeValue evaluates to the value specified above.