Sha256: c68f4dc7bdccbf86e101abb7677c8f1410eb32a4af179acc433259b89dcf8503
Contents?: true
Size: 1.09 KB
Versions: 21
Compression:
Stored size: 1.09 KB
Contents
require_dependency SpatialFeatures::Engine.root.join('app/models/abstract_feature')
class AggregateFeature < AbstractFeature
has_many :features, lambda { |aggregate| where(:spatial_model_type => aggregate.spatial_model_type) }, :foreign_key => :spatial_model_id, :primary_key => :spatial_model_id
# Aggregate the features for the spatial model into a single feature
def refresh
feature_array_sql = <<~SQL
ARRAY[
(#{features.select('ST_UNION(ST_CollectionExtract(geog::geometry, 1))').to_sql}),
(#{features.select('ST_UNION(ST_CollectionExtract(geog::geometry, 2))').to_sql}),
(#{features.select('ST_UNION(ST_CollectionExtract(geog::geometry, 3))').to_sql})
]
SQL
# Remove empty features so ST_COLLECT doesn't choke. This seems to be a difference between PostGIS 2.x and 3.x
self.geog = ActiveRecord::Base.connection.select_value <<~SQL
SELECT COALESCE(ST_Collect(unnest)::geography, ST_GeogFromText('MULTIPOLYGON EMPTY'))
FROM (SELECT unnest(#{feature_array_sql})) AS features
WHERE NOT ST_IsEmpty(unnest)
SQL
self.save!
end
end
Version data entries
21 entries across 21 versions & 1 rubygems