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NOTE

Info pertaining to native FQL will largely be omitted for conciseness, refer to the native FQL docs for more info regarding native FQL.

CalculateDistance

CalculateDistance(to, from);

Description

Given two objects to and from, which both contain lat and lon fields, approximates the distance in meters between to and from. Note that while this distance calculation isn't perfect, it's stil quite accurate.

Parameters

to and from

// REQUIRED
{
  // REQUIRED
  lat: 6.859673258469451, // latitude
  // REQUIRED
  lon: 52.0573310026579 // longitude
}

Returns

A float representing an approximation of the meters between to and from.

CreateGeoSpatialIndex

CreateGeoSpatialIndex(geohashParams, indexParams);

Description

Very similar in usage to the native FQL function CreateIndex, with the only major difference being geohashParams which describes your geohash field.

Parameters

geohashParams

// REQUIRED
{
  // REQUIRED
  // this will eventually be passed into a Select call as the first arg,
  // as implied by the field's name "SelectPath"
  SelectPath: ["data", "location", "geohash"], // example

  // OPTIONAL
  minLength: 3 // default, meant for S2 Quadkeys

  // OPTIONAL
  maxLength: 32 // default, meant for S2 Quadkeys
}

indexParams

// REQUIRED
{

  // OPTIONAL
  values: [
    // the geohash will always be returned as the first value,
    // whether it was specified or not
    { field: geohashParams.SelectPath } // default
  ],

  // SOME REQUIRED (inherited from CreateIndex)
  ...restOfCreateIndexParams
}

Returns

An object containing the metadata about the CreateIndex operations used under the hood.

GeoSearch

GeoSearch(indexName, center, radius, options);

Description

When pointed to an index for prefix searching on geohashes, provides an FQL expression for you to execute. The FQL expression, when executed, will return a SetRef roughly representing the indexed documents found within radius meters of the center coordinates (i.e. roughly searches for indexed documents within a search circle).

Parameters

indexName

// REQUIRED
"<NAME_OF_PREFIX_SEARCHABLE_INDEX>";

center

// REQUIRED
{
  // REQUIRED
  lat: 6.859673258469451, // latitude
  // REQUIRED
  lon: 52.0573310026579 // longitude
}

radius

// REQUIRED
1000; // a positive number of meters

options

// OPTIONAL
{
  // OPTIONAL
  // maximum number of FaunaDB read ops allowed for this FQL expression
  maxReadOps: 10, // default

  // OPTIONAL
  // this library saves read ops when it can
  // through various optimizations;
  // when set to true, any saved read ops will be NOT be respent
  // to make the GeoSearch higher resolution
  disableBonusReadOps: false, // default

  // OPTIONAL
  // when true, returns an object containing additonal information
  // rather than just the FQL expression
  verbose: false, // default
}

Returns

A float representing an approximation of meters between to and from.

latLonToGeohash

latLonToGeohash(coordinates);

Description

Given a set of coordinates, will generate an S2 Quadkey, which we refer to as a "geohash" throughout this library. In the future, more geohash types (e.g. H3) will likely be supported.

Parameters

coordinates

// REQUIRED
{
  // REQUIRED
  lat: 6.859673258469451, // latitude
  // REQUIRED
  lon: 52.0573310026579 // longitude
}

Returns

An S2 Quadkey. For more info, please refer to the docs for the s2-geometry npm package.