Module: Serega::ClassMethods

Included in:
Serega
Defined in:
lib/serega.rb

Overview

Serializers class methods

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#config ⇒ SeregaConfig (readonly)

Returns current config

Returns:



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# File 'lib/serega.rb', line 102

def config
  @config
end

Instance Method Details

#attribute(name, **opts, &block) ⇒ Serega::SeregaAttribute

Adds attribute

Patched in:

  • plugin :presenter (additionally adds method in Presenter class)

Parameters:

  • name (Symbol) —

    Attribute name. Attribute value will be found by executing ‘object.<name>`

  • opts (Hash) —

    Options to serialize attribute

  • block (Proc) —

    Custom block to find attribute value. Accepts object and context.

Returns:



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# File 'lib/serega.rb', line 178

def attribute(name, **opts, &block)
  attribute = self::SeregaAttribute.new(name: name, opts: opts, block: block)
  attributes[attribute.name] = attribute
end

#attributes ⇒ Hash

Lists attributes

Returns:

  • (Hash) —

    attributes list



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# File 'lib/serega.rb', line 153

def attributes
  @attributes ||= {}
end

#batch(name, value = nil, &block) ⇒ #call

Defines a batch loader

Examples:

batch :tags, PostTagsLoader

with block

batch_loader(:tags) do |posts|
  Tags.where(post: posts).group(:post_id).pluck(:post_id, Arel.sql('ARRAY_AGG(tags.tag ORDER BY tag)')).to_h
end

attribute :tags, batch: :tags, value: { |post, batch:| batch[:tags][post.id] }

with context

batch_loader(:tags) do |posts, ctx:|
  next {} if ctx[:bot]

  Tags.where(post: posts).group(:post_id).pluck(:post_id, Arel.sql('ARRAY_AGG(tags.tag ORDER BY tag)')).to_h
end

attribute :tags, batch: :tags, value: { |post, batch:| batch[:tags][post.id] }

Parameters:

  • name (Symbol) —

    A batch loader name

  • value (#call) (defaults to: nil) —

    Batch loader

  • block (Proc) —

    Batch loader

Returns:

  • (#call) —

    Batch loader

Raises:



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# File 'lib/serega.rb', line 211

def batch(name, value = nil, &block)
  raise SeregaError, "Batch loader must be defined with a callable value or block" if (value && block) || (!value && !block)

  batch_loader = self::SeregaBatchLoader.new(name: name, block: value || block)
  batch_loaders[batch_loader.name] = batch_loader
end

#batch_loaders ⇒ Hash

Lists defined batch loaders

Returns:

  • (Hash) —

    batch loaders list



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# File 'lib/serega.rb', line 162

def batch_loaders
  @batch_loaders ||= {}
end

#call(object, opts = nil) ⇒ Hash Also known as: to_h

Serializes provided object to Hash

Parameters:

  • object (Object) —

    Serialized object

  • opts (Hash, nil) (defaults to: nil) —

    Serializer modifiers and other instantiating options

Options Hash (opts):

  • :only (Array, Hash, String, Symbol) —

    The only attributes to serialize

  • :except (Array, Hash, String, Symbol) —

    Attributes to hide

  • :with (Array, Hash, String, Symbol) —

    Attributes (usually hidden) to serialize additionally

  • :validate (Boolean) —

    Validates provided modifiers (Default is true)

  • :context (Hash) —

    Serialization context

  • :many (Boolean) —

    Set true if provided multiple objects (Default ‘object.is_a?(Enumerable)`)

Returns:

  • (Hash) —

    Serialization result



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# File 'lib/serega.rb', line 232

def call(object, opts = nil)
  opts ||= FROZEN_EMPTY_HASH
  initiate_keys = config.initiate_keys

  if opts.empty?
    modifiers_opts = FROZEN_EMPTY_HASH
    serialize_opts = nil
  else
    opts.transform_keys!(&:to_sym)
    serialize_opts = opts.except(*initiate_keys)
    modifiers_opts = opts.slice(*initiate_keys)
  end

  new(modifiers_opts).to_h(object, serialize_opts)
end

#plugin(name, **opts) ⇒ class<Module>

Enables plugin for current serializer

Parameters:

  • name (Symbol, Class<Module>) —

    Plugin name or plugin module itself

  • opts (Hash) —

    ] Plugin options

Returns:

  • (class<Module>) —

    Loaded plugin module

Raises:



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# File 'lib/serega.rb', line 111

def plugin(name, **opts)
  raise SeregaError, "This plugin is already loaded" if plugin_used?(name)

  plugin = SeregaPlugins.find_plugin(name)

  # We split loading of plugin to three parts - before_load, load, after_load:
  #
  # - **before_load_plugin** usually used to check requirements and to load additional plugins
  # - **load_plugin** usually used to include plugin modules
  # - **after_load_plugin** usually used to add config options
  plugin.before_load_plugin(self, **opts) if plugin.respond_to?(:before_load_plugin)
  plugin.load_plugin(self, **opts) if plugin.respond_to?(:load_plugin)
  plugin.after_load_plugin(self, **opts) if plugin.respond_to?(:after_load_plugin)

  # Store attached plugins, so we can check it is loaded later
  config.plugins << (plugin.respond_to?(:plugin_name) ? plugin.plugin_name : plugin)

  plugin
end

#plugin_used?(name) ⇒ Boolean

Checks plugin is used

Parameters:

  • name (Symbol, Class<Module>) —

    Plugin name or plugin module itself

Returns:

  • (Boolean) —

    Is plugin used



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# File 'lib/serega.rb', line 138

def plugin_used?(name)
  plugin_name =
    case name
    when Module then name.respond_to?(:plugin_name) ? name.plugin_name : name
    else name
    end

  config.plugins.include?(plugin_name)
end