FieldSuggestions

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Developer

Example Implementation

field-suggestions.fn.tsx

import {FieldSuggestions as HeadlessFieldSuggestions} from '@coveo/headless';
import {useEffect, useState, FunctionComponent} from 'react';
 
interface FieldSuggestionsProps {
  controller: HeadlessFieldSuggestions;
}
 
export const FieldSuggestions: FunctionComponent<FieldSuggestionsProps> = (
  props
) => {
  const {controller} = props;
  const [state, setState] = useState(controller.state);
 
  useEffect(() => controller.subscribe(() => setState(controller.state)), []);
 
  const onInput = (text: string) => {
    if (text === '') {
      controller.clear();
      return;
    }
    controller.updateText(text);
  };
 
  return (
    <div>
      <input onInput={(e) => onInput(e.currentTarget.value)} />
      <ul>
        {state.values.map((facetSearchValue) => (
          <li
            key={facetSearchValue.rawValue}
            onClick={() => controller.select(facetSearchValue)}
          >
            {facetSearchValue.displayValue} ({facetSearchValue.count} results)
          </li>
        ))}
      </ul>
    </div>
  );
};
 
// usage
 
/**
 * ```tsx
 * const facetOptions: FacetOptions = {field: 'author'};
 * const options: FieldSuggestionsOptions = {facet: facetOptions};
 * const controller = buildFieldSuggestions(engine, {options});
 *
 * <FieldSuggestions controller={controller} />;
 * ```
 */

The FieldSuggestions controller provides query suggestions based on a particular facet field.

For example, you could use this controller to provide auto-completion suggestions while the end user is typing an item title.

This controller is a wrapper around the basic facet controller search functionality, and thus exposes similar options and properties.

Methods

clear

Resets the query and empties the suggestions.

search

Requests field suggestions based on a query.

select

Filters the search using the specified value.

If a facet exists with the configured facetId, selects the corresponding facet value.

Parameters

showMoreResults

Shows more field suggestions for the current query.

singleSelect

Filters the search using the specified value, deselecting others.

If a facet exists with the configured facetId, selects the corresponding facet value while deselecting other facet values.

Parameters

updateCaptions

Updates the captions of field suggestions.

Parameters

  • captions: Record<string, string>

    A dictionary that maps field values to field suggestion display names.

updateText

Requests field suggestions based on a query.

Parameters

  • text: string

    The query to search.

subscribe

Adds a callback that’s invoked on state change.

Parameters

  • listener: () => void

    A callback that’s invoked on state change.

Returns Unsubscribe: A function to remove the listener.

Attributes

state

Properties

  • isLoading: boolean

    Whether the request for field suggestions is in progress.

  • moreValuesAvailable: boolean

    Whether more field suggestions are available.

  • query: string

    The query used to request field suggestions.

  • values: FieldSuggestionsValue[]

    The field suggestions.

Initialize

buildFieldSuggestions

Creates a FieldSuggestions controller instance.

This controller initializes a facet under the hood, but exposes state and methods that are relevant for suggesting field values based on a query. It’s important not to initialize a facet with the same facetId but different options, because only the options of the controller which is built first will be taken into account.

Parameters

  • engine: SearchEngine

    The headless engine.

  • props: FieldSuggestionsProps

    The configurable FieldSuggestions controller properties.

Returns FieldSuggestions

FieldSuggestionsProps

The configurable FieldSuggestions controller properties.

Properties

FieldSuggestionsOptions

The options for the FieldSuggestions controller.

Properties

  • facet: FacetOptions

    The options used to register the facet used by the field suggestions controller.

FacetOptions

Properties

  • field: string

    The field whose values you want to display in the facet.

  • allowedValues?: string[]

    Specifies an explicit list of allowedValues in the Search API request.

    If you specify a list of values for this option, the facet uses only these values (if they are available in the current result set).

    The maximum amount of allowed values is 25.

    Default value is undefined, and the facet uses all available values for its field in the current result set.

  • customSort?: string[]

    Identifies the facet values that must appear at the top, in this order. This parameter can be used in conjunction with the sortCriteria parameter.

    Facet values not part of the customSort list will be sorted according to the sortCriteria.

    The maximum amount of custom sort values is 25.

    The default value is undefined, and the facet values will be sorted using only the sortCriteria.

  • facetId?: string

    A unique identifier for the controller. By default, a random unique identifier is generated.

  • facetSearch?: FacetSearchOptions

    Facet search options.

  • filterFacetCount?: boolean

    Whether to exclude the parents of folded results when estimating the result count for each facet value.

    Default: true

  • hasBreadcrumbs?: boolean

    Specifies whether breadcrumbs appear for the facet

    Default: true

  • injectionDepth?: number

    The maximum number of results to scan in the index to ensure that the facet lists all potential facet values.

    Note: A high injectionDepth may negatively impact the facet request performance.

    Minimum: 0

    Default: 1000

  • numberOfValues?: number

    The number of values to request for this facet. Also determines the number of additional values to request each time this facet is expanded, and the number of values to display when this facet is collapsed.

    Minimum: 1

    Default: 8

  • resultsMustMatch?: 'allValues' | 'atLeastOneValue'

    The criterion to use for specifying how results must match the selected facet values.

    Default: atLeastOneValue

  • sortCriteria?: 'score' | 'alphanumeric' | 'alphanumericDescending' | 'occurrences' | 'automatic'

    The criterion to use for sorting returned facet values.

    The sortCriteria option does not apply when making a facet search request. It is only used for sorting returned facet values during a regular Coveo search request.

    Learn more about sortCriteria values and the default behavior of specific facets in the Search API documentation.

    Default: automatic

FacetSearchOptions

Properties

  • captions?: Record<string, string>

    A dictionary that maps index field values to facet value display names.

  • numberOfValues?: number

    The maximum number of values to fetch.

    Default: 10

  • query?: string

    The query to search the facet values with.

FieldSuggestionsValue

Properties

  • count: number

    An estimated number of result items matching both the current query and the filter expression that would get generated if this field suggestion was selected.

  • displayValue: string

    The custom field suggestion display name, as specified in the captions argument of the FieldSuggestion controller.

  • rawValue: string

    The original field value, as retrieved from the field in the index.

Unsubscribe

Call signatures

  • (): void;