winnow/lib/normalize-query-options/id-field.js

Apply sql-like filters to GeoJSON

const _ = require('lodash')
/**
 * Ensure idField is set if metadata doesn't have a value but a field named OBJECTID is present
 * @param {object} metadata
 */
function normalizeIdField (options, features = []) {
  const metadata = _.get(options, 'collection.metadata')
  const idField = extractIdField(metadata, features[0])

  if (shouldWarnIdFieldIsMissingFromData(idField, features)) {
    console.warn('WARNING: requested provider has "idField" assignment, but this property is not found in properties of all features.')
  }

  return idField
}

function extractIdField ({ idField, fields } = {}, feature = {}) {
  if (idField) return idField

  // metadata.idField is not set, but fields array includes OBJECTID, use that as idField
  if (_.find(fields, { name: 'OBJECTID' })) return 'OBJECTID'

  const properties = feature.properties || feature.attributes
  if (_.has(properties, 'OBJECTID') && properties.OBJECTID !== null) return 'OBJECTID'

  return null
}

function shouldWarnIdFieldIsMissingFromData (idField, features) {
  if (process.env.NODE_ENV === 'production' || process.env.KOOP_WARNINGS === 'suppress' || !idField || features.length === 0) return
  const propertiesFromFirstFeature = _.get(features, '[0].properties') || _.get(features, '[0].attributes', {})
  return propertiesFromFirstFeature[idField] === undefined
}

module.exports = normalizeIdField