discourse/lib/theme_settings_manager.rb
Alan Guo Xiang Tan b1495884eb
PERF: Avoid saving ThemeSetting twice when creating new db override (#26076)
Why this change?

When creating a new theme setting that does not have a corresponding row
in the `theme_settings` table, we end up writing to the database twice
because `ActiveRecord::Base#save!` is called once before the `value`
or `json_value` column is updated again with another database query with
another call to `ActiveRecord::Base#save!`.

What does this change do?

Adds the column to be updated to argument for the `ActiveRecord::Base#create!`
method call so that we only have one write query to the database.
2024-03-07 16:38:11 +08:00

102 lines
2.3 KiB
Ruby

# frozen_string_literal: true
class ThemeSettingsManager
attr_reader :name, :theme, :default
def self.types
ThemeSetting.types
end
def self.cast_row_value(row)
type_name = self.types.invert[row.data_type].downcase.capitalize
klass = "ThemeSettingsManager::#{type_name}".constantize
klass.cast(row.value)
end
def self.create(name, default, type, theme, opts = {})
type_name = self.types.invert[type].downcase.capitalize
klass = "ThemeSettingsManager::#{type_name}".constantize
klass.new(name, default, theme, opts)
end
def self.cast(value)
value
end
def initialize(name, default, theme, opts = {})
@name = name.to_sym
@default = default
@theme = theme
@opts = opts
@types = self.class.types
end
def value
has_record? ? db_record.value : default
end
def type_name
self.class.name.demodulize.downcase.to_sym
end
def type
@types[type_name]
end
def description
@opts[:description] # Old method of specifying description. Is now overridden by locale file
end
def requests_refresh?
@opts[:refresh]
end
def value=(new_value)
ensure_is_valid_value!(new_value)
value = new_value.to_s
record = has_record? ? update_record!(value:) : create_record!(value:)
record.value
end
def db_record
# theme.theme_settings will already be preloaded, so it is better to use
# `find` on an array, rather than make a round trip to the database
theme.theme_settings.to_a.find do |i|
i.name.to_s == @name.to_s && i.data_type.to_s == type.to_s
end
end
def update_record!(args)
db_record.tap { |instance| instance.update!(args) }
end
def create_record!(args)
record = ThemeSetting.new(name: @name, data_type: type, theme: @theme, **args)
record.save!
record
end
def has_record?
db_record.present?
end
def ensure_is_valid_value!(new_value)
return if new_value.nil?
error_messages = ThemeSettingsValidator.validate_value(new_value, type, @opts)
raise Discourse::InvalidParameters.new error_messages.join(" ") if error_messages.present?
end
def has_min?
min = @opts[:min]
(min.is_a?(::Integer) || min.is_a?(::Float)) && min != -::Float::INFINITY
end
def has_max?
max = @opts[:max]
(max.is_a?(::Integer) || max.is_a?(::Float)) && max != ::Float::INFINITY
end
end