Class: Feature

Inherits:
AbstractFeature show all
Defined in:
app/models/feature.rb

Constant Summary

Constants inherited from AbstractFeature

AbstractFeature::FEATURE_TYPES

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from AbstractFeature

area_in_square_meters, #cache_derivatives, cache_key, collection_cache_key, #envelope, #feature_bounds, #geojson, geojson, intersecting, invalid, #kml, lines, #make_valid?, points, polygons, total_intersection_area_in_square_meters, valid, with_metadata, within_distance, within_distance_of_point, without_caching_derivatives

Class Method Details

.cache_derivatives(options = {}) ⇒ Object

Features are used for display so we also cache their KML representation



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# File 'app/models/feature.rb', line 19

def self.cache_derivatives(options = {})
  super
  update_all "    kml          = ST_AsKML(geog, 6),\n    kml_lowres   = ST_AsKML(geom_lowres, \#{options.fetch(:lowres_precision, lowres_precision)}),\n    kml_centroid = ST_AsKML(centroid)\n  SQL\nend\n".squish

.defer_aggregate_refresh(&block) ⇒ Object 



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# File 'app/models/feature.rb', line 28

def self.defer_aggregate_refresh(&block)
  start_at = Feature.maximum(:id).to_i + 1
  output = without_aggregate_refresh(&block)

  where(:id => start_at..Float::INFINITY).refresh_aggregates

  return output
end

.refresh_aggregates ⇒ Object 



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# File 'app/models/feature.rb', line 45

def self.refresh_aggregates
  # Find one feature from each spatial model and trigger the aggregate feature refresh
  ids = where.not(:spatial_model_type => nil)
          .where.not(:spatial_model_id => nil)
          .group('spatial_model_type, spatial_model_id')
          .pluck('MAX(id)')

  # Unscope so that newly built AggregateFeatures get their type column set correctly
  AbstractFeature.unscoped { where(:id => ids).find_each(&:refresh_aggregate) }
end

.without_aggregate_refresh ⇒ Object 



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# File 'app/models/feature.rb', line 37

def self.without_aggregate_refresh
  old = Feature.automatically_refresh_aggregate
  Feature.automatically_refresh_aggregate = false
  yield
ensure
  Feature.automatically_refresh_aggregate = old
end

Instance Method Details

#automatically_refresh_aggregate? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'app/models/feature.rb', line 61

def automatically_refresh_aggregate?
  # Check if there is a spatial model id because nothing prevents is from creating a Feature without one. Depending on
  # how you assign a feature to a record, you may end up saving it before assigning it to a record, thereby leaving
  # this field blank.
  spatial_model_id? && automatically_refresh_aggregate && saved_change_to_geog?
end

#refresh_aggregate ⇒ Object 



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# File 'app/models/feature.rb', line 56

def refresh_aggregate
  aggregate_feature&.destroy # Destroy the existing aggregate feature to ensure its cache key changes when it is refreshed
  create_aggregate_feature!
end