Adding seeds for testing and staging purposes: One map, several layers…

db/seeds.rb

@@ -1,5 +1,8 @@
 # This file should contain all the record creation needed to seed the database with its default values.
 # The data can then be loaded with the rails db:seed command (or created alongside the database with db:setup).
+require 'json'
+
+# Minimal data to have a admin user
 
 Group.find_or_create_by( title: 'Admins' )
 
@@ -8,4 +11,90 @@
   user.role = 'admin'
   user.group = Group.find_by( title: 'Admins' )
   puts 'Created a first group and a user'
-end
+end
+
+
+
+module DatabaseSeeding
+  class MapSeeder
+    def self.seed_map_structure(json_file_path )
+      json_data = File.read(Rails.root.join('db', 'seeds', json_file_path))
+      map_data = JSON.parse(json_data)
+
+      ActiveRecord::Base.transaction do
+        # Create or update the map
+        map = create_or_update_map(map_data['map'])
+
+        # Process layers
+        process_layers(map, map_data['map']['layer'])
+      rescue StandardError => e
+        puts "Error seeding data: #{e.message}"
+        puts e.backtrace
+        raise ActiveRecord::Rollback
+      end
+    end
+
+
+    def self.create_or_update_map(map_data)
+      map_attributes = map_data.except('layer')
+
+      # prepare the map attributes
+      map_attributes.delete_if { |_, v| v.nil? }
+      group = Group.find_by( title: 'Admins' )
+      map_attributes['group_id'] = group.id
+      map_attributes.delete('owner')
+
+      if existing_map = Map.find_by(title: map_attributes['title'])
+        existing_map.tap { |map| map.update!(map_attributes) }
+      else
+        Map.create!(map_attributes)
+      end.tap { |map| puts "Processed Map: #{map_attributes['title']}" }
+    end
+
+    def self.process_layers(map, layers)
+      return unless layers.is_a?(Array)
+
+      layers.each do |layer_data|
+        layer = create_or_update_layer(map, layer_data)
+        process_places(layer, layer_data['places'])
+      end
+    end
+
+    def self.create_or_update_layer(map, layer_data)
+      layer_attributes = layer_data.except('places').except('places_with_relations')
+      layer_attributes['map_id'] = map.id
+      layer_attributes.delete_if { |_, v| v.nil? }
+
+      if existing_layer = Layer.find_by(id: layer_attributes['id'])
+        existing_layer.tap { |layer| layer.update!(layer_attributes) }
+      else
+        Layer.create!(layer_attributes)
+      end.tap { |layer| puts "-- Processed Layer: #{layer_attributes['title']}" }
+    end
+
+    def self.process_places(layer, places)
+      return unless places.is_a?(Array)
+
+      places.each do |place_data|
+        create_or_update_place(layer, place_data)
+      end
+    end
+
+    def self.create_or_update_place(layer, place_data)
+      place_attributes = place_data.clone
+      place_attributes['layer_id'] = layer.id
+
+      # Filter attributes to only include those that exist in the Place model
+      valid_attributes = place_attributes.slice(*Place.column_names)
+
+      if existing_place = Place.find_by(id: valid_attributes['id'])
+        existing_place.tap { |place| place.update!(valid_attributes) }
+      else
+        Place.create!(valid_attributes)
+      end.tap { |place| puts "---- Processed Place: #{place.title}" }
+    end
+  end
+end # module DatabaseSeeding  
+
+# Seed the database with a sample dataset of public parks in Hamburg West
+DatabaseSeeding::MapSeeder.seed_map_structure('public-parks-and-greens-in-hamburg-west.json')