Improve the Version Proof of the Gem

[azeveco]

Context

There were still a few problems between versions, like:

• Inheritance of the models
• Loading models based on Rails version
• Building a feature's identifier
• insert_all of the BulkToggler
• Building tracking analytics data
• Writing the with_features scope from the lib/togglefy/assignable.rb with SQL

Resolution

Inheritance of the models && Loading models based on Rails version

There were still a few inheritance problems inside the Togglefy::Feature and the Togglefy::FeatureAssignment models. Also, there were in-model conditional validations to choose the best approach of a few things, which may cause performance problems.

For this, we've changed it how the models load, by requiring a specific model based on the Rails version only once, during the initialize of the server:

Togglefy/app/models/togglefy/feature.rb

Lines 5 to 11 in 997882d

	if Rails::VERSION::MAJOR >= 7
	require_relative "#{ROOT_PATH}/lib/models/rails_7/feature"
	elsif Rails::VERSION::MAJOR >= 5
	require_relative "#{ROOT_PATH}/lib/models/rails_5/feature"
	else
	require_relative "#{ROOT_PATH}/lib/models/rails_legacy/feature"
	end

The above example applies also to the Togglefy::FeatureAssignments.

Thanks to that, we've stopped doing in-model conditional validations.

Building a feature's identifier

Older Ruby versions did not allow a keyword argument separator from the .parameterize method.

Because of that, we've changed to parameterize without separator keyword argument and gsub to change the - to _.

insert_all of the BulkToggler

Before Rails 6, there were no insert_all method inside ActiveRecord. So, because of that, we've implemented a insert_all that will only be used when the Rails version is lower than 6.

Togglefy/lib/togglefy/services/bulk_toggler.rb

Lines 151 to 176 in 604a36b

	# Build values to send to custom insert_all method for Rails versions below 6
	#
	# @param rows [Array<Hash>] The rows to insert.
	def insert_all_flow(rows)
	columns = rows.first.keys
	values = rows.map do |row|
	"(#{columns.map do |col|
	ActiveRecord::Base.connection.quote(row[col])
	end.join(", ")}, #{ActiveRecord::Base.sanitize(Time.zone.now)}, #{ActiveRecord::Base.sanitize(Time.zone.now)})"
	end
	insert_all(columns, values)
	end
	# Implements the insert_all method for Rails versions below 6.
	#
	# @param columns [Array] The columns to insert.
	# @param values [Array] The values of the columns to insert.
	def insert_all(columns, values)
	sql = <<-SQL.squish
	INSERT INTO togglefy_feature_assignments (#{columns.push(:created_at, :updated_at).join(", ")})
	VALUES #{values.join(", ")}
	SQL
	ActiveRecord::Base.connection.execute(sql)
	end

This adds an inline conditional to check the Rails version, but since the bulk enable isn't an operation that's done a frequently, there's no need to improve it like we did with the models. There we had to do this because many checks were calling the models.

Building tracking analytics data

The yet unreleased analytics feature was using a filter_map method to build the analytics/tracking data of a feature.

That's a problem because this method was only introduced in Ruby 2.7 and we say we support Ruby 2.4.10. So we changed that to a simpler map.

Writing the with_features scope from the lib/togglefy/assignable.rb with SQL

The with_features scope was having a problem with Rails 4.2.8. It was losing context/alias of the join with the feature_assignments, so when entering the where clause wasn't working because it could not find the table feature_assignments.

Well, it wasn't able to find it because it didn't exist. It's supposed to be togglefy_feature_assignments.

Because of that, we've decided to write the join with SQL to force the alias and make sure it will remember it.

Togglefy/lib/togglefy/assignable.rb

Lines 29 to 37 in 604a36b

	scope :with_features, lambda { |feature_ids|
	joins("INNER JOIN togglefy_feature_assignments AS feature_assignments
	ON feature_assignments.assignable_id = #{table_name}.id AND
	feature_assignments.assignable_type = '#{name}'")
	.where(feature_assignments: {
	feature_id: feature_ids
	})
	.distinct
	}

Impacted processes/locations

• Togglefy::Feature
• Togglefy::FeatureAssignment
• Togglefy::ScopedBulkWrapper && BulkToggler
• Analytics
• Assignable

References

#45