add interval data type to ActiveRecord

config/initializers/pg_interval_5_2.rb

@@ -0,0 +1,94 @@
+# frozen_string_literal: true
+
+# from https://gist.github.com/Envek/7077bfc36b17233f60ad
+
+# PostgreSQL interval data type support from https://github.com/rails/rails/pull/16919
+# Works with both Rails 5.2 and 6.0
+# Place this file to config/initializers/
+
+require "active_support/duration"
+
+# activerecord/lib/active_record/connection_adapters/postgresql/oid/interval.rb
+module ActiveRecord
+  module ConnectionAdapters
+    module PostgreSQL
+      module OID # :nodoc:
+        class Interval < Type::Value # :nodoc:
+          def type
+            :interval
+          end
+
+          def cast_value(value)
+            case value
+            when ::ActiveSupport::Duration
+              value
+            when ::String
+              begin
+                ::ActiveSupport::Duration.parse(value)
+              rescue ::ActiveSupport::Duration::ISO8601Parser::ParsingError
+                nil
+              end
+            else
+              super
+            end
+          end
+
+          def serialize(value)
+            case value
+            when ::ActiveSupport::Duration
+              value.iso8601(precision: self.precision)
+            when ::Numeric
+              # Sometimes operations on Times returns just float number of seconds so we need to handle that.
+              # Example: Time.current - (Time.current + 1.hour) # => -3600.000001776 (Float)
+              value.seconds.iso8601(precision: self.precision)
+            else
+              super
+            end
+          end
+
+          def type_cast_for_schema(value)
+            serialize(value).inspect
+          end
+        end
+      end
+    end
+  end
+end
+
+# activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+require 'active_record/connection_adapters/postgresql_adapter'
+PostgreSQLAdapterWithInterval = Module.new do
+  def initialize_type_map(m = type_map)
+    super
+    m.register_type "interval" do |*_args, sql_type|
+      precision = extract_precision(sql_type)
+      ::ActiveRecord::ConnectionAdapters::PostgreSQLAdapter::OID::Interval.new(precision: precision)
+    end
+  end
+
+  def configure_connection
+    super
+    execute('SET intervalstyle = iso_8601', 'SCHEMA')
+  end
+
+  ActiveRecord::Type.register(:interval, ::ActiveRecord::ConnectionAdapters::PostgreSQLAdapter::OID::Interval, adapter: :postgresql)
+end
+ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.prepend(PostgreSQLAdapterWithInterval)
+
+# activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
+require 'active_record/connection_adapters/postgresql/schema_statements'
+module SchemaStatementsWithInterval
+  def type_to_sql(type, limit: nil, precision: nil, scale: nil, array: nil, **)
+    case type.to_s
+    when 'interval'
+      case precision
+      when nil;  "interval"
+      when 0..6; "interval(#{precision})"
+      else raise(ActiveRecordError, "No interval type has precision of #{precision}. The allowed range of precision is from 0 to 6")
+      end
+    else
+      super
+    end
+  end
+end
+ActiveRecord::ConnectionAdapters::PostgreSQL::SchemaStatements.prepend(SchemaStatementsWithInterval)