adapter.rb in chrono_model-0.9.1

- old
+ new

@@ -150,11 +150,11 @@
                 FROM #{TEMPORAL_SCHEMA}.#{table_name}
               ]
             end
           end
 
-          chrono_alter(table_name) { super table_name, options, &block }
+          chrono_alter(table_name, options) { super table_name, options, &block }
         else
           if options[:temporal] == false && is_chrono?(table_name)
             # Remove temporal features from this table
             #
             execute "DROP VIEW #{table_name}"
@@ -565,12 +565,12 @@
           _on_temporal_schema { tables }.each do |table_name|
             next unless is_chrono?(table_name)
             metadata = chrono_metadata_for(table_name)
             version = metadata['chronomodel']
 
-            if version.blank? # FIXME
-              raise Error, "ChronoModel found structures created by a too old version. Cannot upgrade right now."
+            if version.blank?
+              upgrade_from_legacy(table_name)
             end
 
             next if version == current
 
             logger.info "ChronoModel: upgrading #{table_name} from #{version} to #{current}"
@@ -585,10 +585,50 @@
         #
         logger.error message
         $stderr.puts message
       end
 
+      def upgrade_from_legacy(table_name)
+        # roses are red
+        # violets are blue
+        # and this is the most boring piece of code ever
+        history_table = "#{HISTORY_SCHEMA}.#{table_name}"
+        p_pkey = primary_key(table_name)
+
+        execute "ALTER TABLE #{history_table} ADD COLUMN validity tsrange;"
+        execute """
+          UPDATE #{history_table} SET validity = tsrange(valid_from,
+            CASE WHEN extract(year from valid_to) = 9999 THEN NULL
+                 ELSE valid_to
+            END
+          );
+        """
+
+        execute "DROP INDEX #{history_table}_temporal_on_valid_from;"
+        execute "DROP INDEX #{history_table}_temporal_on_valid_from_and_valid_to;"
+        execute "DROP INDEX #{history_table}_temporal_on_valid_to;"
+        execute "DROP INDEX #{history_table}_inherit_pkey"
+        execute "DROP INDEX #{history_table}_recorded_at"
+        execute "DROP INDEX #{history_table}_instance_history"
+        execute "ALTER TABLE #{history_table} DROP CONSTRAINT #{table_name}_valid_from_before_valid_to;"
+        execute "ALTER TABLE #{history_table} DROP CONSTRAINT #{table_name}_timeline_consistency;"
+        execute "DROP RULE #{table_name}_upd_first ON #{table_name};"
+        execute "DROP RULE #{table_name}_upd_next ON #{table_name};"
+        execute "DROP RULE #{table_name}_del ON #{table_name};"
+        execute "DROP RULE #{table_name}_ins ON #{table_name};"
+        execute "DROP TRIGGER history_ins ON #{TEMPORAL_SCHEMA}.#{table_name};"
+        execute "DROP FUNCTION #{TEMPORAL_SCHEMA}.#{table_name}_ins();"
+        execute "ALTER TABLE #{history_table} DROP COLUMN valid_from;"
+        execute "ALTER TABLE #{history_table} DROP COLUMN valid_to;"
+
+        execute "CREATE EXTENSION IF NOT EXISTS btree_gist;"
+
+        chrono_create_view_for(table_name)
+        _on_history_schema { add_history_validity_constraint(table_name, p_pkey) }
+        _on_history_schema { chrono_create_history_indexes_for(table_name, p_pkey) }
+      end
+
       def chrono_metadata_for(table)
         comment = select_value(
           "SELECT obj_description(#{quote(table)}::regclass)",
           "ChronoModel metadata for #{table}") if table_exists?(table)
 
@@ -809,12 +849,12 @@
 
       # In destructive changes, such as removing columns or changing column
       # types, the view must be dropped and recreated, while the change has
       # to be applied to the table in the temporal schema.
       #
-      def chrono_alter(table_name)
+      def chrono_alter(table_name, opts = {})
         transaction do
-          options = chrono_metadata_for(table_name)
+          options = chrono_metadata_for(table_name).merge(opts)
 
           execute "DROP VIEW #{table_name}"
 
           _on_temporal_schema { yield }
 